With the urbanization of Swedish cities, densification has emerged as a sustainable ideal in urban planning. As new buildings and hard surfaces replace more green spaces and open areas, the Earth´s climate is becoming warmer, and the consequences of rising temperatures are becoming more tangible. In densely built environments, the warm climate is further exacerbated due to the urban heat island effect, which means that the temperature difference between urban and rural areas can reach several degrees. This affects the local climate and has serious consequences for the people who live and stay in the cities, including increased heat stress and health risks. Through climate-conscious planning, where heat-reducing measures are implemented, the heat island effect can be mitigated and thereby creating favorable urban climates. This work focuses on the impact of the densification ideal on the heat island effect and human living environments. In the literature review, heat islands and their consequences are discussed to emphasize the importance of planning for rising temperatures and to identify temperature-reducing measures. The study examines a typical densification project to understand how heat-reducing measures can be integrated into existing urban areas and suggest actions that should be introduced early in the planning process. The measures have been proposed using two methods; a qualitative document study and a site analysis. The site analysis conducted in Ebbepark, Linköping aimed to create an understanding of aspects in the built environment. Through the site analysis and document study, proposals for measures were developed, which then formed the basis for the design proposal in Ebbepark. The results showed that the integration of heat-reducing measures in densely built areas significantly contributes to the improvement of people´s living environments by counteracting the heat island effect and creating a more pleasant microclimate. Implementation of vegetation, high-reflective materials, and water features results in significant temperature reductions. To effectively counteract the heat island effect, these measures can be integrated into urban planning, both in new and existing densification areas. Heat-reducing measures should also be incorporated into municipalities’ overall planning documents to promote the development of sustainable and resilient urban environments. / I takt med urbaniseringen av Sveriges städer har förtätning växt fram som ett hållbart ideal i den fysiska planeringen. Under tiden som ny bebyggelse och hårdgjorda ytor ersätter allt fler grönområden och friytor blir jordens klimat allt varmare och de stigande temperaturernas konsekvenser mer påtagliga. I den tätbebyggda miljön förstärks det varma klimatet ytterligare med anledning av den urbana värmeöeffekten, som innebär att skillnaden i temperatur mellan stad och landsbygd kan nå flera grader. Detta påverkar det lokala klimatet och får allvarliga konsekvenser för de människor som bor och vistas i städerna, däribland ökad värmestress och hälsorisker. Genom en klimatmedveten planering där värmereducerande åtgärder implementeras kan värmeöeffekten mildras och därmed goda stadsklimat skapas. Arbetet handlar om förtätningsidealets påverkan på värmeöeffekten och människans livsmiljö. I kunskapsöversikten behandlas värmeöar och dess konsekvenser för att betona vikten av att planera för stigande temperaturer samt för att kunna identifiera temperaturreducerande åtgärder. Arbetet undersöker ett typiskt förtätningsprojekt för att förstå hur värmereducerande åtgärder kan integreras i befintliga områden och föreslår åtgärder som bör införas tidigt i planeringsprocessen. Åtgärderna har föreslagits med hjälp av två metoder; en kvalitativ dokumentstudie och en platsanalys. Platsanalysen som genomförts i Ebbepark, Linköping syftade till att skapa förståelse för aspekter i den byggda miljön. Genom platsanalysen och dokumentstudien kunde förslag på åtgärder tas fram, vilka sedan lade grund för gestaltningsförslaget i Ebbepark.  Arbetets resultat visade att integreringen av värmereducerande åtgärder i tätbebyggda områden avsevärt bidrar till förbättringen av människors livsmiljö genom att motverka värmeöeffekten och skapa ett mer behagligt mikroklimat. Implementering av vegetation, högreflekterande material och vatteninslag resulterar i betydande temperaturminskningar. För att effektivt motverka värmeöeffekten kan dessa åtgärder integreras i den fysiska planeringen, både i nya och befintliga förtätningsområden. Värmereducerande åtgärder bör också införlivas i kommuners övergripande planeringsdokument för att främja utvecklingen av hållbara och motståndskraftiga urbana miljöer.

The purpose of this thesis work is to improve the perceived climate comfort in larger truck cabins since the European commission’s new stronger carbon dioxide standards have introduced an update to the EU 96/53 directive. This directive increases the dimensions and weights of heavy truck motor vehicles, extending the driver’s cabin length by 500 mm in order to increment the truck’s energy efficiency and aerodynamics. This update was seen also as an enabler to improve the truck driver’s performance, comfort and preference towards Scania. Since the cabin of the truck is to be considered the place where the driver spends the most of its time, ensuring the driver’s comfort when resting inside means to ensure the accomplishment of their labor safely. One system used to provide comfort in the cabin when resting is the climate control unit. This unit creates an inner climate controlled environment by providing warm or cool air through an installed Heating Ventilation and Air Conditioning (HVAC) system. In order to introduce a new auxiliary unit, the design thinking methodology was chosen. This allowed to ground the proposed concepts on the actual needs of the final users. Based on their input, the aforementioned concepts were analyzed and downsized in order to prototype and test the selected ones. The final concepts of a 500 mm larger cabin were tested in a climate chamber under warm and cold conditions: 37°C and -15°C respectively. Then, these concepts were compared against the short cabin (current cabin) and the 500 mm larger cabin without any mounted prototype. During each test, a thermal manikin was placed in the cabin’s bed in order to obtain not only temperature readings, but also the estimated comfort that the user would sense under these circumstances. As it could be expected, the 500 mm larger cabin without any added concept presented a temperature degradation of the current HVAC system compared to the short cabin. The areas of temperature concentration (warm or cold) were identified, being the rear wall of the cabin the most affected. The implementation of the concepts compared to the larger cabin gave positive results, reducing the time to reach the set temperature in the HVAC system controls in both warm and cold environments. The analysis of the results lead to the conclusion that the enlargement of a truck creates a need to maintain or improve the behavior of its HVAC system. The implementation of an auxiliary unit to the main system in the rear of the cabin showed not only temperature enhancements, but also a thermal comfort improvement for the user, allowing it to rest and therefore, to fulfill its tasks with the best mental and physical conditions. / Syftet med det här examensarbetet är att förbättra den upplevda klimatkomforten i större lastbilshytter sedan EU-kommissionens nya hårdare koldioxidstandarder har medfört en uppdatering av EU-direktivet 96/53. Detta direktiv ökar dimensionerna och vikterna för tunga lastbilar och förlänger förarhyttens längd med 500 mm för att öka lastbilens energieffektivitet och aerodynamik. Denna uppdatering sågs också som en möjlighet att förbättra lastbilschaufförens prestation, komfort och inställning till Scania. Eftersom lastbilshytten är den plats där föraren tillbringar den största delen av sin tid, är det viktigt att säkerställa förarens komfort när han eller hon vilar i hytten för att kunna utföra sitt arbete på ett säkert sätt. Ett system som används för att ge föraren komfort när han eller hon vilar i hytten är klimatenhet. Denna enhet skapar en inre klimatkontrollerad miljö genom att tillföra varm eller kall luft via ett installerat HVAC-system (Heating Ventilation and Air Conditioning). För att introducera ett nytt hjälpenhet valdes metodiken design thinking. Detta gjorde det möjligt för de föreslagna koncepten att baseras på de faktiska behoven hos de slutliga användarna. Baserat på deras input, gjordes analyser av de tidigare nämnda koncepten för att sedan välja ut, prototypa och testa de utvalda. De slutliga koncepten med en 500 mm större hytt testades i en klimatkammare under varma och kalla förhållanden: 37°C respektive -15°C. Därefter jämfördes dessa koncept med den korta hytten (nuvarande hytt) och den 500 mm större hytten utan någon monterad prototyp. Under varje test placerades en klimatdocka i hyttens säng för att inte bara få temperaturavläsningar, utan också den uppskattade komfort som användaren skulle känna under dessa omständigheter. Som väntat uppvisade den 500 mm större hytten utan något extra koncept en temperaturförsämring av det nuvarande HVAC-systemet jämfört med den korta hytten. Områdena med varm eller kall temperatur identifierades och kabinens bakre vägg var den som påverkades mest. Implementeringen av koncepten jämfört med den större hytten gav positiva resultat, vilket minskade tiden för att nå den inställda temperaturen för HVAC-systemet i både varma och kalla miljöer. Analysen av resultaten ledde till slutsatsen att förstoringen av en lastbil skapar ett behov av att bibehålla eller förbättra beteendet hos dess HVAC-system. Implementeringen av en hjälpenhet till huvudsystemet i den bakre delen av hytten visade inte bara temperaturförbättringar, men också en förbättring av klimatkomforten för användaren, vilket gör att föraren den kan vila och därmed utföra sina uppgifter med de bästa mentala och fysiska förutsättningarna.

[ES] Tradicionalmente, los espacios abiertos al aire libre han sido utilizados por los habitantes como lugares clave para la vida social, donde la gente pasa su tiempo libre. Sin embargo, debido a problemas de confort térmico, se ha reducido su uso. Es necesario mantener estos espacios activos mejorando el nivel de confort térmico. Hasta ahora, los estudios anteriores han carecido de un enfoque morfológico integral de las áreas urbanas y su impacto en el confort térmico. Entre los diversos componentes del entorno construido, las superficies verticales ocupan una gran parte del área, y el papel de estas superficies en la radiación térmica ha sido descuidado en los estudios a escala urbana. Este estudio tiene como objetivo desarrollar una respuesta efectiva para el confort térmico humano en espacios urbanos al aire libre, considerando la configuración geométrica de las superficies verticales. El estudio comienza con una revisión exhaustiva de estudios indios previos que se centran en el confort térmico en exteriores. Después de adquirir los conocimientos necesarios en el campo y comprender las lagunas existentes en los estudios de confort térmico en India, se presta atención a los sitios y las respectivas zonas climáticas. El estudio se centra en dos espacios abiertos comerciales en el clima compuesto de Delhi y cuatro barrios residenciales diferentes en Jaisalmery, analizando el efecto de las superficies verticales en el confort térmico humano al aire libre. Se llevaron a cabo simulaciones utilizando el software Envi-met para obtener varios índices climáticos, que se analizaron junto con parámetros físicos definidos por la relación altura-ancho, el factor de visión del cielo y la orientación de las superficies verticales. Se realizaron mediciones de campo para validar los resultados obtenidos de las simulaciones de Envi-met, y también se realizó una encuesta para comprender el nivel subjetivo de confort térmico. Los resultados se analizaron para la temporada de verano, ya que el invierno no es dominante y tiene una duración corta en el año. El estudio revela que las superficies verticales y su geometría tienen un efecto significativo en el confort térmico exterior. Las geometrías urbanas complejas pueden generar diferentes niveles de confort térmico en proximidad cercana, observándose variaciones en el nivel de confort térmico debido a los cambios en las geometrías de las superficies verticales alrededor de los espacios abiertos. El acceso solar, la sombra y la velocidad del viento también influyen en el confort térmico, siendo evidente el efecto de los parámetros geométricos en las sensaciones térmicas de los usuarios. Una mayor relación altura-ancho puede ayudar a mejorar el nivel de sensación térmica, aunque la influencia del factor de visión del cielo es menos prominente. Este estudio proporcionará pautas para arquitectos, arquitectos paisajistas, planificadores e ingenieros para diseñar espacios abiertos al aire libre cómodos desde el punto de vista térmico. Además, se abordará seriamente problemas a gran escala como el efecto de isla de calor urbano. Los espacios exteriores ya no se considerarán como espacios adicionales una vez que se construyan los edificios, y desde la etapa conceptual, los diseñadores considerarán el espacio exterior al diseñar los edificios y las funciones interiores. Este estudio también sentará las bases para futuras investigaciones, ya que abre varias direcciones que requieren atención. Considero que la investigación en este campo tiene un alcance amplio en el futuro, dado que la temperatura de la Tierra está aumentando debido al calentamiento global. Es responsabilidad de los arquitectos diseñar espacios de manera que la experiencia del usuario no se vea afectada mientras se mantiene el nivel de confort térmico. / [CA] Tradicionalment, els habitants han utilitzat espais a l'aire lliure com a llocs clau per a la vida social, on la gent passa el seu temps lliure. Tanmateix, a causa dels problemes de confort tèrmic, el seu ús s'ha reduït. Cal mantenir aquests espais actius, millorant el nivell de confort tèrmic. Fins ara, els estudis anteriors no han tingut un enfocament morfològic integral de les zones urbanes i el seu impacte en el confort tèrmic. Entre els diversos components de l'entorn construït, les superfícies verticals ocupen una gran part de la zona, i el paper d'aquestes superfícies en la radiació tèrmica s'ha descuidat en estudis a escala urbana. Aquest estudi pretén desenvolupar una resposta efectiva per al confort tèrmic humà en espais a l'aire lliure urbà, tenint en compte la configuració geomètrica de superfícies verticals. L'estudi comença amb una revisió exhaustiva dels estudis indis anteriors que se centren en el confort tèrmic a l'aire lliure. Després d'adquirir els coneixements necessaris en el camp i comprendre les llacunes en els estudis de confort tèrmic a l'Índia, es presta atenció als llocs i a les zones climàtiques respectives. L'estudi se centra en dos espais oberts comercials en el clima compost de Delhi i quatre barris residencials diferents a Jaisalmery, analitzant l'efecte de les superfícies verticals sobre el confort tèrmic humà a l'aire lliure. Es van realitzar simulacions mitjançant el programari Envi-met per obtenir diversos índexs climàtics, que es van analitzar juntament amb paràmetres físics definits per la relació amplada d'alçada, el factor de visió del cel i l'orientació de les superfícies verticals. Es van realitzar mesures de camp per validar els resultats obtinguts de les simulacions Envi-met, i també es va realitzar una enquesta per comprendre el nivell subjectiu de confort tèrmic. Els resultats es van analitzar per a la temporada d'estiu, ja que l'hivern no és dominant i té una durada curta a l'any. L'estudi revela que les superfícies verticals i la seva geometria tenen un efecte significatiu en el confort tèrmic exterior. Les geometries urbanes complexes poden generar diferents nivells de confort tèrmic a prop, s'observen variacions en el nivell de confort tèrmic a causa dels canvis en les geometries de les superfícies verticals al voltant dels espais oberts. L'accés solar, l'ombra i la velocitat del vent també influeixen en el confort tèrmic, l'efecte dels paràmetres geomètrics sobre les sensacions tèrmiques dels usuaris és evident. Una proporció d'amplada d'alçada més alta pot ajudar a millorar el nivell de sensació tèrmica, tot i que la influència del factor de visió del cel és menys destacada. Aquest estudi proporcionarà directrius perquè arquitectes, arquitectes paisatgístics, planificadors i enginyers dissenyin espais a l'aire lliure termalament còmodes. A més, es tractaran seriosament problemes a gran escala com l'efecte insular de calor urbana. Els espais exteriors ja no es consideraran espais addicionals un cop construïts edificis i des de l'etapa conceptual, Els dissenyadors tindran en compte l'espai exterior a l'hora de dissenyar edificis i funcions interiors. Aquest estudi també posarà les bases per a futures investigacions, ja que obre diverses direccions que requereixen atenció. Crec que la investigació en aquest camp té un abast ampli en el futur, ja que la temperatura de la Terra augmenta a causa de l'escalfament global. És responsabilitat dels arquitectes dissenyar espais perquè l'experiència de l'usuari no es vegi afectada mantenint el nivell de confort tèrmic. / [EN] Traditionally the outdoor open spaces were used by inhabitants; the social life was largely dependent on the user spending time in outdoor spaces. These spaces including streets, markets, shopping precincts, community centers, plazas, and playgrounds play a vital role in the social life of communities. Due to thermal comfort issues, the use of these spaces is declining. It is necessary to keep these spaces active by improving the thermal comfort level. The focus on a single morphological entity of an urban area and its effect on thermal comfort level is lacking in earlier studies. Out of the various components of the built environment, the vertical surface is one of the components which occupies the maximum area. The role of vertical surfaces in thermal radiation remains unresolved, unobserved, unexplored, and unapplied at the urban scale studies. This study aims to develop an effective response for human thermal comfort level in an outdoor urban space affected by the geometrical configuration of vertical surfaces. The study begins with an in-depth review of Indian studies which are focused on outdoor thermal comfort. After grasping the necessary knowledge in the field and understanding the gaps present in thermal comfort studies in India, the sites and the respective climatic zones were given attention. This study is focused on two different commercial open spaces in the composite climate of Delhi and four different residential neighborhoods in Jaisalmer and discussed the effect of vertical surfaces on human thermal comfort in an outdoor environment. Software simulations with Envi-met were performed to achieve various climatic indices. These indices were analyzed with physical parameters defined by the height-to-width ratio, sky view factor, and the orientation of vertical surfaces. Field measurements were conducted to validate the results obtained from Envi-met simulation outputs. Alongside this, a questionnaire survey was conducted to understand the subjective thermal comfort level. Results were analyzed for the summer season since winter is not dominant and lasts only for a short duration of the year. The study shows that the vertical surfaces and their geometry have high effects on outdoor thermal comfort. Complex urban geometries can result in varying thermal comfort levels. Within small proximity, the variation in thermal comfort level can be observed due to the change in the vertical surface geometries around the open spaces. The effect of solar access, shade, and wind velocity is seen in the thermal comfort level. The effect of geometrical parameters is evident in the thermal sensation votes of the user. A higher height-to-width ratio can help improve the thermal sensation level, whereas the effect of the sky view factor is less prominent. This study will give guidelines for architects, landscape architects, planners, and engineers to design thermally comfortable outdoor open spaces. It will also create a serious approach while considering the broad-scale issues such as the urban heat island effect. The outdoor spaces will not be considered as the leftover spaces once the building is constructed, whereas right from the conceptualization the designers will think about the outdoor space while designing the buildings and indoor functions. The study will also act as a base for future research since this research opens up several directions which need attention. I feel research in this field is of great scope in the future as the earth's temperature is increasing due to global warming. It is an architect's responsibility to design spaces in such a way that user experience is not affected while maintaining the thermal comfort level. / Khaire, JD. (2023). Effect of Vertical Urban Surfaces on Human Thermal Comfort in an Outdoor Environment [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/202304

thermal manikin, thermophysiological model, thermal comfort, climatic chamber, clothing thermal resistence

The history of surgery is nearly as old as the human race. Control of wound infection has always been an essential part of any surgical procedure, and is still an important challenge in hospital operating rooms today. For patients undergoing surgery there is always a risk that they will develop some kind of postoperative complication. It is widely accepted that airborne bacteria reaching a surgical site are mainly staphylococci released from the skin flora of the surgical staff in the operating room and that even a small fraction of those particles can initiate a severe infection at the surgical site.  Wound infections not only impose a tremendous burden on healthcare resources but also pose a major threat to the patient. Hospital-acquired infection ranks amongst the leading causes of death within the surgical patient population. A broad knowledge and understanding of sources and transport mechanisms of infectious particles may provide valuable possibilities to control and minimize postoperative infections. This thesis contributes to finding solutions, through analysis of such mechanisms for a range of ventilation designs together with investigation of other factors that can influence spread of infection in hospitals, particularly in operating rooms. The aim of this work is to apply the techniques of computational fluid dynamics in order to provide better understanding of air distribution strategies that may contribute to infection control in operating room and ward environments of hospitals, so that levels of bacteria-carrying particles in the air can be reduced while thermal comfort and air quality are improved.  A range of airflow ventilation principles including fully mixed, laminar and hybrid strategies were studied. Airflow, particle and tracer gas simulations were performed to examine contaminant removal and air change effectiveness. A number of further influential parameters on the performance of airflow ventilation systems in operating rooms were examined and relevant measures for improvement were identified. It was found that airflow patterns within operating room environments ranged from laminar to transitional to turbulent flows. Regardless of ventilation system used, a combination of all airflow regimes under transient conditions could exist within the operating room area. This showed that applying a general model to map airflow field and contaminant distribution may result in substantial error and should be avoided. It was also shown that the amount of bacteria generated in an operating room could be minimized by reducing the number of personnel present. Infection-prone surgeries should be performed with as few personnel as possible. The initial source strength (amount of colony forming units that a person emits per unit time) of staff members can also be substantially reduced, by using clothing systems with high protective capacity. Results indicated that horizontal laminar airflow could be a good alternative to the frequently used vertical system. The horizontal airflow system is less sensitive to thermal plumes, easy to install and maintain, relatively cost-efficient and does not require modification of existing lighting systems. Above all, horizontal laminar airflow ventilation does not hinder surgeons who need to bend over the surgical site to get a good view of the operative field. The addition of a mobile ultra-clean exponential laminar airflow screen was also investigated as a complement to the main ventilation system in the operating room. It was concluded that this system could reduce the count of airborne particles carrying microorganisms if proper work practices were maintained by the surgical staff. A close collaboration and mutual understanding between ventilation experts and surgical staff would be a key factor in reducing infection rates. In addition, effective and frequent evaluation of bacteria levels for both new and existing ventilation systems would also be important. / Tidigt i mänsklighetens utveckling har kirurgin funnits med i bilden. Hantering av infektioner har genom tiderna varit en oundviklig del av alla kirurgiska ingrepp, och finns kvar ännu idag som en viktig utmaning i operationssalar på sjukhus. För patienter som genomgår kirurgi finns alltid en risk att de efter ingreppet utvecklar någon behandlingsrelaterad komplikation. Allmänt accepterat är att de luftburna bakterier som når operationsområdet huvudsakligen består av stafylokocker frigjorda från hudfloran av operationspersonalen i operationssalen, och att endast en liten del av dessa partiklar behövs för att initiera en allvarlig infektion i det behandlade området. Sårinfektioner innebär inte bara en enorm börda för hälso- och sjukvårdsresurser, utan utgör också en betydande risk för patienten. På sjukhus förvärvad infektion finns bland de främsta dödsorsakerna i kirurgiska patientgrupper.. En bred kunskap och förståelse av spridningsmekanismer och källor till infektionsspridande partiklar kan ge värdefulla möjligheter att kontrollera och minimera postoperativa infektioner. Denna avhandling bidrar till lösningar genom analys av en rad olika ventilationssystem tillsammans med undersökning av andra faktörer som kan påverka infektionsspridningen på sjukhus, främst i operationssalar. Syftet med arbetet är att med hjälp av CFD-teknik (Computational Fluid Dynamics) få bättre förståelse för olika luftspridningsmekanismers betydelse vid ventilation av operationssalar och vårdinrättningar på sjukhus, så att halten av bacteriebärande partiklar i luften kan minskas samtidigt som termisk komfort och luftkvalité förbättras.  Flera luftflödesprinciper för ventilation inklusive omblandade strömning, riktad (laminär) strömning och hybridstrategier har studerats. Simuleringar av luft-, partikel- och spårgasflöden gjordes för alla fallstudier för att undersöka partikelevakuering och luftomsättning i rummet. Flera viktiga parametrar som påverkar detta undersöktes och relevanta förbättringar  föreslås i samarbete med industrin. Av resultaten framgår att mängden genererade bakterier i en operationssal  kan begränsas genom att minska antalet personer i operationsteamet. Infektionsbenägna operationer skall utföras med så lite personal som möjligt. Den initiala källstyrkan (mängden kolonibildande enheter som en person avger per tidsenhet) från operationsteamet kan avsevärt minskas om högskyddande kläder används. Av resultaten framgår också att ett horisontellt (laminärt) luftflöde kan vara ett bra alternativ till det ofta använda vertikala luftflödet. Ett horisontellt luftflöde är mindre känsligt för termisk påverkan från omgivningen, enkelt att installera och underhålla, relativt kostnadseffektivt och kräver vanligen ingen förändring av befintlig belysningsarmatur. Framför allt begränsar inte denna ventilationsprincip kirurgernas rörelsemönster. De kan luta kroppen över operationsområdet utan att hindra luftflödet. En flyttbar flexibel skärm för horisontell spridning av ultraren ventilationsluft i tillägg till ordinarie ventilation undersöktes också. Man fann att denna typ av tilläggsventilation kan minska antalet luftburna partiklar som bär mikroorganismer om operationspersonalen följer en strikt arbetsordning. Bra samarbete och förståelse mellan ventilationsexperter och operationsteamet på sjukhuset är nyckeln till att få ner infektionsfrekvensen. Det är också viktigt med effektiva och frekventa utvarderingar av bakteriehalten i luften, för såväl nya  som befintliga ventilationssystem. / <p>QC 20160129</p>

This study presents air distribution systems that are based on confluent jets; this system can be of interest for the establishment of indoor environments, to fulfill the goals of indoor climate and energy-efficient usage. The main objective of this study is to provide deeper understanding of the flow field development of a supply device that is designed based on wall confluent jets and to investigate the ventilation performance by experimental and numerical methods. In this study, the supply device can be described as an array of round jets on a flat surface attached to a side wall. Multiple round jets that issue from supply device apertures are combined at a certain distance downstream from the device and behave as a united jet or so-called confluent jets. Multiple round jets that are generated from the supply device move downward and are attached to the wall at the primary region, due to the Coanda effect, and then they become wall confluent jets until the floor wall is reached. A wall jet in a secondary region is formed along the floor after the stagnation region. The characteristics of the flow field and the ventilation performance of conventional wall confluent jets and modified wall confluent jets supply devices are investigated experimentally in an office test room. The study of the modified wall confluent jets is intended to improve the efficiency of the conventional one while maintaining acceptable thermal comfort in an office environment. The results show that the modified wall confluent jets supply device can provide acceptable thermal comfort for the occupant with lower airflow rate compared to the conventional wall confluent jets supply device. Numerical predictions using three turbulence models (renormalization group (RNG k– ε), realizable (Re k– ε), and shear stress transport (SST k– ω) are evaluated by measurement results. The computational box and nozzle plate models are used to model the inlet boundary conditions of the nozzle device. In the isothermal study, the wall confluent jets in the primary region and the wall jet in the secondary region, when predicted by the three turbulence models, are in good agreement with the measurements. The non-isothermal validation studies show that the SST k– ω model is slightly better at predicting the wall confluent jets than the other two models. The SST k– ω model is used to investigate the effects of the nozzle diameter, number of nozzles, nozzle array configuration, and inlet discharge height on the ventilation performance of the proposed wall confluent jets supply device. The nozzle diameter and number of nozzles play important roles in determining the airflow pattern, temperature field, and draught distribution. Increased temperature stratification and less draught distribution are achieved by increasing the nozzle diameter and number of nozzles. The supply device with smaller nozzle diameters and fewer nozzles yields rather uniform temperature distribution due to the dominant effect of mixing. The flow behavior is nearly independent of the inlet discharge height for the studied range. The proposed wall confluent jets supply device is compared with a mixing supply device, impinging supply device and displacement supply device. The results show that the proposed wall confluent jets supply device has the combined behavior of both mixing and stratification principles. The proposed wall confluent jets supply device provides better overall ventilation performance than the mixing and displacement supply devices used in this study. This study covers also another application of confluent jets that is based on impinging technology. The supply device under consideration has an array of round jets on a curve. Multiple jets issue from the supply device aperture, in which the supply device is positioned vertically and the jets are directed against a target wall. The flow behavior and ventilation performance of the impinging confluent jets supply device is studied experimentally in an industrial premise. The results show that the impinging confluent jets supply device maintains acceptable thermal comfort in the occupied zone by creating well-distributed airflow during cold and hot seasons.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-06-30T14:45:00Z No. of bitstreams: 1 IÁNGLIO MÁRCIO TRAVASSOS DUARTE JÁCOME - DISSERTAÇÃO PPGEA 2005..pdf: 24122932 bytes, checksum: 394218ab3657d7c67f9f55e27833d36b (MD5) / Made available in DSpace on 2018-06-30T14:45:00Z (GMT). No. of bitstreams: 1 IÁNGLIO MÁRCIO TRAVASSOS DUARTE JÁCOME - DISSERTAÇÃO PPGEA 2005..pdf: 24122932 bytes, checksum: 394218ab3657d7c67f9f55e27833d36b (MD5) Previous issue date: 2005-03 / O objetivo deste trabalho foi medir os efeitos de diferentes sistemas de acondicionamento ambiental sobre o desempenho de poedeiras comerciais semi pesadas vermelhas nas três fases de criação entre setembro de 2003 a maio de 2004. Foram utilizados dois galpões com acondicionamento térmico diferentes, sendo um com cobertura de telhas de cimento amianto (GTA) e outro com cobertura de telhas cerâmicas (GTC) e avaliados a temperatura do ar, índices de temperatura do globo negro e umidade (ITGU), carga térmica de radiação (CTR), umidade relativa do ar (UR) e níveis de ruído no interior das instalações. O desempenho das poedeiras, foi avaliado pela produção total e pela qualidade dos ovos. A fase experimental foi realizada em galpão de criação para poedeiras comerciais. Os índices ambientais foram medidos diariamente, em intervalos de duas horas, das 8 às 16 horas, nas áreas interna e externa dos galpões experimentais. A análise das médias mostrou que na fase de pinteiro, durante as primeiras semanas de vida, houve falha no aquecimento das pintainhas, com temperaturas atingindo no máximo 31,27°C no interior das instalações, sendo que a partir da 5a semana houve um inverso e as instalações não proporcionaram níveis adequados de conforto com temperaturas elevadas. A fase de recria foi a que apresentou maiores falhas nos níveis de conforto térmico e a fase de postura apresentou níveis adequados de conforto na maior parte dos horários analisados durante a fase experimental em virtude dos altos índices pluviométricos registrados na região nos meses de pesquisa. Os resultados foram analisados estatisticamente por meio do teste t de Tukey ao nível de 1 e 5% de probabilidade, tendo em vista que o mesmo é recomendado para comparação de médias nas condições deste trabalho. Concluiu-se, baseado nos índices térmicos ambientais, que o sistema com telhas cerâmicas apresentou os melhores resultados de Temperatura ambiente, ITGU, CTR e UR, nas fases de recria e postura e baseado nos índices de desempenho produtivo das aves, a produção atingiu média de 90% no GTC e 87,20% no GTA. Em relação à qualidade do ovo houve diferenças estatísticas (P< 0,05) entre as aves mantidas nos diferentes galpões em relação ao peso do ovo e do albúmem, enquanto que as demais variáveis não apresentaram diferenças. / The objective of this work was to measure the effects of different systems of environmental conditions on the performance of red commercial semi-heavy hens in the three creation phases among September of 2003 to May of 2004. Two hangars were used with different thermal packaging, one with asbestos cement tiles covering (GTA) and other with ceramic tiles covering (GTC). The temperature of the air, indexes of temperatura of the black globe and humidity (ITGU), thermal load of radiation (CTR), relative humidity of the air (UR) and noise leveis inside the facilities were evaluated. The hens performance was evaluated by the total production and for the quality of the eggs. The experimental phase was accomplished at creation hangar for commercial hens. The environmental indexes were measured daily, in intervals of two hours, of the 8 to the 16 hours, in the internai and externai áreas of the experimental hangars. The analysis of the averages showed that in the birth phase, during the first weeks of life, there was failings in the heating of the bird, with temperaturas reaching at the most 31,27°C inside the facilities, and starting from to 5th week there was an inverse behavior and the facilities didn"t provide appropriate leveis of comfort with high temperaturas. The phase of rebirth was the one that presented larger flaws in the leveis of thermal comfort and the postura phase presented appropriate leveis of comfort in most of the schedules analyzed during the experimental phase because of the high rain indexes registered in the area in the months of research. The results were analyzed by statistical methods through the test t of Tukey at the levei of 1 and 5% of probability. It was concluded, based on the environmental thermal indexes, that the system with ceramic tiles presented the best room temperature results, ITGU, CTR and UR in the phases of recreation and postura and based on the indexes of productive performance of the birds - the production reached average of 90% in GTC and 87,20% in GTA. In relation to the quality of the eggs, there were statistical differences (P <0,05) among the birds maintained at the different hangars in relation to the weight of the egg and of the egg white, while the other variables didn't present differences.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-09-03T18:39:37Z No. of bitstreams: 1 ALBÉRIO LOPES RODRIGUES - TESE PPGMV 2012..pdf: 780552 bytes, checksum: 40fc6d8909d346efc5c79f859193d403 (MD5) / Made available in DSpace on 2018-09-03T18:39:37Z (GMT). No. of bitstreams: 1 ALBÉRIO LOPES RODRIGUES - TESE PPGMV 2012..pdf: 780552 bytes, checksum: 40fc6d8909d346efc5c79f859193d403 (MD5) Previous issue date: 2012 / O objetivo desse trabalho foi avaliar a influência do ambiente de pastejo sobre o comportamento e de dois ambientes de pré ordenha sobre as respostas produtivas, fisiológicas, hormonais e a qualidade do leite de vacas da raça Pardo-Suíça criadas em sistema Biodinâmico de produção. A pesquisa foi dividida em quatro capítulos. No capítulo I, por meio da literatura vigente, buscou-se informações sobre a importância da utilização do sombreamento natural e artificial na pastagem, e ainda, a eficiência da sombra e dos sistemas de resfriamento na pré ordenha de vacas leiteiras, verificando-se, serem estratégias importantes para o conforto e a produção látea desses animais. No capítulo II, foi realizada uma revisão bibliográfica sobre as características produtivas e a qualidade do leite bovino produzido ecológica e convencionalmente, observando-se que a leve inferioridade na produção e nos constituintes do leite ecológico foi devido a baixa utilização de tecnologias no manejo geral desse sistema. No capítulo III, Avaliou-se a influência do ambiente de pastejo sobre o comportamento alimentar, ruminação e ócio, noturna e diuturnamente (Ensaio I) de 32 vacas, divididas nos níveis de alta e baixa produção láctea, e o efeito dos ambientes de pré ordenha de sombra e sol (ensaio II) sobre as variáveis fisiológicas desses animais. As vacas de baixa produção alimentaram-se por mais tempo nas horas quentes do dia, quando comparados aos de alta, mas os animais de ambos os níveis produtivos pastejaram mais durante o dia que à noite (Ensaio I). Nos ambientes de pré ordenha (Ensaio II), as vacas mais produtivas foram mais sensíveis ao calor que as de baixa produção e, o ambiente de pré ordenha sombreado foi eficiente em manter as variáveis fisiológicas dentro da faixa aceitável para os bovinos leiteiros, independentemente dos níveis produtivos. No capítulo IV, avaliou-se o efeito dos ambientes de sombra e sol sobre a produção, qualidade do leite e concentração plasmática hormonal de 32 vacas, divididas nos níveis de alta e baixa produção láctea. Assim, verificouse, que o fornecimento de sombra por 1,5 horas antes da ordenha da tarde a vacas leiteiras Pardo-Suíças criadas em sistema Biodinâmico de produção, embora reduza as intempéries climáticas sobre as mesmas, não altera a sua produção e composição láctea. / The objective this work were to assess on grazing in two different environments of pre milking about the behavior in milk from cows of Brown Swiss on the productive responses, physiological, hormonal and quality from the biodynamic production system. That study was put in four chapters. Into the first chapter, we looked for information about the importance in to use the natural and artificial shading in grasslands and about the shadow efficiency and about the cooling systems on the milking in the milkmaid to confirm about the importance strategy for the comfort and the milk production. On the chapter II, we did the review in the papers about the production characterize and the milk qualify from the cattle form the ecological and traditional system to observe about the low in the production and the composition in the ecological milk was because the short technology in the handling in the used system. Into the chapter III we look for to evaluate the influence about the ambience on grazing about the food behavior rumination and resting, day and night (test I) of 32 cows, we had 16 in low and 16 in up production and look for about action of ambiences in pre milking on the sun and in with out sun. The cows from low production eating for up time in hot hours in the day when we make to comparison with the up production cows but the animal with the both level grazing more in the day (test I). In the ambiences in pre milking (Test II), the cows with the high production were more sensitive about the hot weather than the animal in the cooling weather and the ambience of pre milking with out sun were more efficiency with the physiological variations in the acceptance level for the cattle apart the two production levels. Into the chapter IV, we evaluated the effect of sun and shade environments on production, milk quality and hormonal plasma concentration of 32 cows, divided into high and low levels of milk production. In fact, it was found, that shade for 1.5 hours before the pre milking afternoon the cows in Brown Swiss from biodynamic production system, while reducing the influence weather in the cows, does not improve its yield and the composition milk.

Made available in DSpace on 2014-07-29T15:03:35Z (GMT). No. of bitstreams: 1 Renata Moreira de Sa e Silva.pdf: 4355719 bytes, checksum: c7e027c64c149741085a933c047cecba (MD5) Previous issue date: 2008-11-08 / The generation of large quantities of solid waste is a great problem faced by urban areas. Like all building materials, the gypsum plaster is a generator of solid waste. The amount and inadequate waste disposal cause serious environmental, social and economical impacts. This requires the search for quick and effective solutions for its management, through the development of specific programs, which aim to minimize these impacts. This study was developed with the purpose to use waste material of the gypsum industry to built low cost houses with better environmental comfort. Also there were motivations for this study the advantages of gypsum, among them thermal and acoustic insulation, and to help managing municipal waste. Thus, it was studied closing masonry with bricks made by the reuse of gypsum plaster which not have sufficient fluidity to make construction frames anymore. In order to verify which mortar better fit this construction system, two different types of settlement mortars were studied: traditional gypsum paste (GC) and traditional mortar (cement, lime and sand) (AT). The aspects of productivity, cost and strength compression of the constructive system were tested. Coatings were also studied, performed with two types of recycled gypsum: wet recycled gypsum (RU) and dry recycled gypsum (RS), varying their proportions and analyzing the performance of them concerning on workability, cracking, tensile strength and for water absorption and permeability, according to the NIT 140 method proposed by CSTC, from Belgium. In order to verify the thermal and acoustic comfort, a prototype was produced with these new materials. The results showed that the traditional mortar (AT) was the most suitable for the construction of closing masonry made by recycled gypsum, the best internal coating was the 25% paste substituition by wet plaster (RU) and external coating the traditional mortar (AT), 1:1:6 mixture proportion, widely used in constructions. In relation to thermal comfort, there was a better thermal attenuation of recycled gypsum prototype in comparison to a soil cement bricks prototype, also with a good accoustic isolation. The results assured technical and financial viability of using these types of coatings in the construction of low cost housing. / A geração de grandes quantidades de resíduos sólidos é um problema crescente nas áreas urbanas. Assim como os demais materiais de construção, o gesso é um gerador de entulho. A quantidade expressiva desse resíduo e o seu descarte inadequado causam graves impactos ambientais, sociais e econômicos. Isto impõe a busca de soluções rápidas e eficazes para sua gestão adequada, através da elaboração de programas específicos, que visem à minimização desses impactos. Este estudo foi desenvolvido com o objetivo de reutilizar um resíduo da indústria de gesso para construir habitações de interesse social visando um melhor conforto ambiental. Também foram motivações para este estudo as vantagens do gesso, dentre elas, isolamento térmico e acústico e a busca de uma forma de gerenciamento dos resíduos urbanos. Para tanto, estudou-se alvenarias de fechamento com tijolos produzidos através do reaproveitamento de pastas de gesso que não possuíam mais fluidez para a confecção de molduras e testando dois tipos de argamassa de assentamento, gesso cola (GC) e argamassa tradicional (AT) de forma a verificar a que melhor se adéqua a este sistema construtivo no aspecto produtividade, custo e resistência à compressão. Estudou-se também, revestimentos executados com dois tipos de gesso reciclado, gesso reciclado úmido (RU) e gesso reciclado seco (RS), variando suas proporções e analisando o desempenho destes quanto à trabalhabilidade e fissuração, resistência de aderência à tração e à absorção e permeabilidade à água, segundo o método do cachimbo , proposto pelo CSTC da Bélgica (NIT 140). Ainda realizou-se a análise do conforto térmico e acústico do protótipo produzido com esses novos materiais alternativos. Os resultados apontaram a argamassa tradicional (AT) como mais adequada à construção de alvenarias de gesso reciclado, destacando-se como revestimento interno a pasta com 25% de substituição por gesso reciclado úmido (RU) e revestimento externo o reboco comum (AT), muito utilizado em construções, traço 1:1:6. O protótipo executado de gesso reciclado ainda ofereceu uma melhor atenuação térmica quando comparado com um protótipo de solo cimento e garantiu um bom isolamento acústico. Após realização de todas as análises, verifica-se a viabilidade técnica e financeira de execução de construções de interesse social com esses materiais alternativos constituídos de gesso.

Dans le contexte énergétique français actuel, deux principaux enjeux émergent. À court terme, des pointes de consommation électrique croissantes sont observées les dernières années pendant la période hivernale. Ces pointes sont fortement liées au chauffage électrique et ont des conséquences économiques, environnementales et sociales importantes. Dans un long terme, des objectifs environnementaux ambitieux ont été fixés au niveau national et européen, nécessitant la technologie de stockage thermique et une gestion efficace de l'environnement bâti. Les Matériaux à Changement de Phase (MCP) ainsi que les dispositifs de type échangeurs thermiques offrent des résultats promettant grâce au stockage thermique et le déplacement des consommations. Dans ce cadre, l’objectif de cette thèse est de développer des solutions de déplacement des consommations énergétiques qui prennent en compte le confort thermique des occupants et la qualité de l’air intérieur. Pour ce faire, deux outils sont nécessaires: un échangeur thermique expérimental (prototype) et un modèle numérique capable de simuler son comportement. L'échangeur contient du MCP macroencapsulé (paraffine) et est conçu de manière à faciliter son intégration dans un système de ventilation. Il a comme but de décaler la consommation due au chauffage électrique vers la période hors pointe. Le dispositif a été caractérisé expérimentalement lors des cycles thermiques complets (charge et décharge) en utilisant une quantité importante de capteurs. Il a ensuite été couplé à une cellule expérimentale, afin de tester des stratégies de contrôle préliminaires. Le modèle numérique est basé sur la discrétisation spatiale et l’établissement du bilan de chaleur des couches considérées, la méthode de la capacité thermique apparente, ainsi que l’utilisation des différences finies. Après validation à l’aide des données expérimentales, le modèle a été utilisé pour optimiser la performance de l'échangeur. Plusieurs paramètres ont été étudiés, y compris les dimensions de l'échangeur, la quantité et les propriétés du MCP, en cherchant la configuration avec le compromis optimal entre la chaleur emmagasinée et le temps nécessaire pour la charge et la décharge. Le modèle numérique a été couplé à un modèle de simulation du bâtiment et un logement de 80m2 a été conçu pour la mise en oeuvre et l'évaluation des stratégies de contrôle, en investiguant différents scénarios sur une période hivernal d’un mois. Les scénarios varient avec une complexité croissante, d'abord en considérant l’effacement énergétique et le confort thermique, ensuite en ajoutant le prix final de la consommation électrique et enfin en prenant compte la qualité de l'air intérieur avec la présence d'une famille de quatre personnes. 6 Cette étude a été menée dans le cadre d'un projet financé par l'Agence National de la Recherche (Stock-Air: ANR-Stock-E) et a également été soutenu par le ministère de l'Ecologie, du Développement durable et de l'Energie. / Considering the current French energy context, two major challenges are emerging. In the short term, significant peak power consumption has been observed in the past few years during the winter season. These peaks are strongly linked to electrical space heating and have important economic, environmental and social implications. In the long term, ambitious environmental goals have been set at national and European levels, requiring thermal storage technology and efficient management of the built environment. As part of the solution, Phase Change Materials (PCM) and heat exchanger applications offer promising results through thermal storage and load shifting techniques. Within this framework, the objective of this thesis is to develop load shifting solutions which also take into account the thermal comfort of the occupants and the indoor air quality. To achieve this, two tools were necessary: an experimental heat exchanger unit (prototype) and a numerical model that accurately simulates its behavior. The exchanger contains macroencapsumated PCM (paraffin) and is conceived in a way that facilitates its integration in a ventilation system. It is aimed to shift space heating electrical consumption from peak to off-peak period. The unit was experimentally characterized, using an important amount of sensors through full thermal cycles (charging and discharging) and was coupled to an experimental test cell, which led to the testing of preliminary control strategies. The numerical model is based on the heat balance approach and the apparent heat capacity method, using finite differences for differential equation solution under Matlab/Simulink environment. After validation with experimental data, the model was used to optimize the performance of the exchanger. Several parameters were investigated, including heat exchanger dimensions, PCM quantity and properties, seeking the configuration with the optimal compromise between stored heat and the time needed for the charging / discharging process. The numerical model was coupled to a building simulation model and an 80m2 dwelling was conceived for control strategies implementation and evaluation, by investigating different scenarios over a one- month winter period. The scenarios vary with increasing complexity, first considering load shifting and thermal comfort, then adding the final price of electricity consumption and finally taking into account the indoor air quality with the presence of a four-person family. This study has been conducted within the framework of a project funded by the French National Research Agency (Stock-Air: ANR-Stock-E) and was also financially supported by the French Ministry of Sustainable Development.