Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 252-255).

Call number: LD2668 .T4 1966 F837 / Master of Science

Thesis (M.Phil.)--Hong Kong University of Science and Technology, 2007. / Includes bibliographical references (leaves 78-82). Also available in electronic version.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

O vestuário é um dos itens considerados como equipamento de proteção individual para ambientes de trabalho. Entre vários aspectos, a roupa se caracteriza como isolante térmico interferindo, assim, na troca térmica do ser humano, entre o corpo e o ambiente. O corpo revestido pela vestimenta pode garantir que não haja troca térmica quando a necessidade é evitar a troca de calor com o ambiente. Porém, quando há essa necessidade, a vestimenta inadequada prejudica o balanço térmico. A Norma Internacional ISO 9920:2007 identifica os valores de isolamento térmico e resistência do vapor d’água das vestimentas. Esses valores, baseados em pesquisas em manequim estático e em condições padronizadas, são utilizados como Índice de Isolamento Térmico de Vestimentas como uma das variáveis que interferem no conforto térmico. Porém algumas pesquisas apontam que pode haver imprecisões nos valores tabelados pela ISO 9920, considerando que esta seja uma variável subjetiva podendo apresentar variabilidade muito maior nos padrões de ocupantes em situações reais comparando-as com as roupas padronizadas utilizadas em laboratórios, as quais têm a média de valores utilizada no cálculo do Voto Médio Estimado. Nesse contexto, essa pesquisa objetivou verificar a existência de imprecisões nos valores tabelados pela ISO 9920 do Índice de Isolamento Térmico da Vestimenta através de duas metodologias estatísticas propostas utilizando como banco de dados uma pesquisa de campo em ambiente industrial do setor metal-mecânico. Conclui-se que para esse ramo de atividade o modelo de conforto térmico apresentou-se eficiente. Entretanto, a variação do conjunto de vestimentas foi baixa, não sendo suficiente para gerar questionamentos quanto aos valores tabelados. Conclui-se também que as imprecisões significativas nos valores de Isolamento Térmico de Vestimenta e, discrepâncias entre o Voto Médio Estimado e as Sensações Térmicas Reais podem ser derivadas da não caracterização correta da roupa. Por isso, a complexidade do conjunto de vestimenta é fator relevante para o conforto térmico. / Clothing is one of those items considered as personal protective equipment for working environments. Among different features, clothing is characterized as thermal insulator interfering, therefore, in the thermal exchange between body and environment. The human body with the clothes on can assure it does not allow thermal exchange when it is necessary to avoid the heat exchange with the environment. However, when this exchange is needed, the inadequate clothing affects the thermal balance. The International Standard ISO 9920 identifies the set of garments with an adequate thermal insulation, considering the insulation itself and the water vapor resistance. The values established in the International Standard, based on researches on static mannequin and on standardized conditions, are used as index for Thermal Insulation of Clothing as one of the variables that affect the thermal comfort. Nevertheless, some studies point out that there may be inaccuracies in the values tabulated by ISO 9920, whereas this is a subjective variable and may have greater variability for the user patterns in real situations compared with the standardized clothes used in laboratories, which have the average values used calculated by the Predicted Mean Vote. In this context, this study had the objective of verifying the existence of inaccuracies in the values tabulated by ISO 9920 of the index of Thermal Insulation of Clothing through two statistical methodologies proposed, using as database a field research in an industrial environment of the metal-mechanic sector. It was concluded that the significant inaccuracies in the values of the clothing thermal insulation and the discrepancies between the Predicted Mean Vote and real thermal sensations can be derived from a lack of characterization of the clothes. Therefore, the garment complexity set is a relevant factor for the thermal comfort.

Multilayer insulation (MLI) has been shown to be the best performing cryogenic insulation system at high vacuum (less than 10-3 torr), and is widely used on spaceflight vehicles. Over the past 50 years, many numerous investigations of MLI have yielded a general understanding of the many variables associated with MLI. MLI has been shown to be a function of variables such as warm boundary temperature, the number of reflector layers, and the spacer material in between reflectors, the interstitial gas pressure and the interstitial gas. Because conduction between reflectors increases with the thickness of the spacer material, and yet the radiation heat transfer is inversely proportional to the number of layers, it stands to reason that the thermal performance of MLI is a function of the number of layers per thickness, or layer density. Empirical equations that were derived based on some of the early tests showed that the conduction term was proportional to the layer density to a power. This power depended on the material combination and was determined by empirical test data. Many authors have graphically shown such optimal layer density, but none have provided any data at such low densities, or any method of determining this density. Keller, Cunnington, and Glassford showed MLI thermal performance as a function of layer density of high layer densities, but they didn’t show a minimal layer density or any data below the supposed optimal layer density. However, it was recently discovered by the author that by manipulating the derived empirical equations and taking a derivative with respect to layer density, a solution for on optimal layer density may be obtained. iv Several manufacturers have begun manufacturing MLI at densities below the analytical optimal density. This trend is apparently based on the theory that increased distance between layers lowers the conductive heat transfer and that there are no limitations on volume. By modifying the circumference of these blankets, the layer density can easily be varied. The most direct method of determining the thermal performance of MLI at cryogenic temperature is by evaporation (or “boil-off”) calorimetry. Several blankets were procured and tested at various layer densities by the Cryogenics Test Laboratory at NASA Kennedy Space Center. The blankets were tested over a wide range of layer densities including the analytical minimum. Several of the blankets were tested at the same insulation thickness while changing the layer density (thus a different number of reflector layers). Heat transfer optimization of the layer density of multilayer insulation systems would remove the variable of layer density from the complex method of designing such insulation systems. Since the layer density is one of the variables that in those complex equations that require more experience to understand fully grasp, this significantly simplifies the blanket design process. Additional testing was performed at various warm boundary temperatures and pressures. The testing and analysis was performed to determine thermal performance data and to simplify the analysis of cryogenic thermal insulation systems.

Thesis (MScEng)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: The focus of this thesis is on South Africa's first micro space satellite SUNSAT, and the thermal modelling thereof. Background theory with relevance to thermal management and control of satellite systems and subsystems is presented. The mission profile and subsystem makeup of SUNSAT is also briefly discussed, with emphasis placed on the physical structure, possible orbit paths, internal heat generation, and the environmental heating. The environmental heating on the satellite surfaces from the direct and reflected earth solar radiation, as well as the earth emitted infrared radiation, is determined from the developed computer program ORBIT-FLUX. This program was used in tandem with numerical programs (developed in house), as well as an outsourced program TAS (Thermal Analysis Systems) to model SUNSAT for two possible orbit paths. The resistance-capacitance formulation method was used to develop the numerical programs, which served initially to establish the validity ofTAS. The first approximated thermal model of SUNSA T's batteries was the 7 lumped-mass model that focused on the batteries since their overheating is the suspected reason for SUNSA T'S failure to complete its mission. A numerical program as well as a similar TAS model was developed, and the results showed correlation to within 3°C. A lumped-mass model of SUNSAT was also developed, both numerically and using TAS. The models were tested and the results showed that the temperatures of the models were sensitive to changes in internal heating as well as varying emissivity and absorptivity. The numerical and TAS lumped-mass model results did not correlate well, possibly due to the higher number of control volumes used in the TAS lumped-mass model. The TAS SUNSAT 2 model was developed as advancement on the lumped-mass model. The higher number of control volumes and the effect of adding solar panels gave a more realistic model of SUNSA T. The results did not show good correlation with actual SUNSA T temperature data possibly due to the fact that the solar panels were not mounted on the model body as they were on SUNSA T; but the TAS SUNSA T 2 model did set the platform for the more advanced TAS SUNSAT 3 model. This thermal model included the effects of the solar panel mountings, and had a higher number of control volumes, which gave a better physical representation of the SUNSAT subsystems. The model was tested for possible orbit paths of SUNSA T. The results showed excellent correlation to actual SUNSA T data. For the comparison of the TAS SUNSA T 3 model results with data from SUNSAT for July 1999 showed that the SUNSA T battery temperature was modelled to within 8°C. And for June 2000, this same comparison was to within 1°C. A thermal management and control case study was done on a simple system (which included a cubic box and an internal solid block with heat generation) to illustrate the effects of using various passive and active thermal control hardware to regulate temperatures. The results showed that internal surfaces painted black provide for maximum heat sharing, and lowest block temperatures. The block temperatures were found to be very sensitive to changes in the cube external optical surface properties. A slight increase in emissivity lowered the block temperature, while a slight increase in absorptivity increased the block temperature. Heat pipes were also found to lower the temperatures of the block and immediate subsystems by providing a path of low thermal resistance to the flow of heat from the block directly to the radiator. The effect of thermal insulation was also investigated. For the two materials (rubber and plastic) that were tested, it was noticed that although insulation material does give more thermal control and predictability over a subsystem by thermally isolating it from its environment, it can cause a subsystem that has heat generation to become too hot. Recommendations were made relating to future micro satellite thermal management and control with regard to; thermal modelling techniques, acquisition of tried software, positioning of temperature sensors for optimisation of thermal data, and the verification of optical surface properties by physical measurement. / AFRIKAANSE OPSOMMING: Hierdie tesis fokus op Suid-Afrika se eerste mikro ruimte satelliet, SUNSAT, en die termiese ontwikkeling daarvan. Agtergrond teorie met betrekking tot die termiese bestuur en kontrole van die satelliet-sisteme en subsisteme word aangebied. Die missie-profiel en die samestelling van die subsisteme word ook kortliks bespreek met die klem op die fisiese strukture, moontlike wentelbane, interne hitte-opwekking, en die omgewingsverhitting. Die omgewingsverhitting op die oppervlaktes van die satelliet, veroorsaak deur direkte en weerkaatste aardlson bestraling, sowel as deur infrarooi bestraling afkomstig van die aarde, word bepaal deur die ontwikkelde rekenaarprogram ORBIT-FLUX. Hierdie program word gebruik in tandem met numeriese programme (intern ontwikkel), so weI as 'n uitgekontrakteerde program TAS (Termiese Analiese Sisteme) om SUNS AT vir twee moontlike wentelbane te modelleer. Die weerstandskapasitansie formuleringsmetode is gebruik om die numeriese programme te ontwikkel. Hierdie programme is oorspronklik gebruik om die validiteit van TAS vas te stel. Die eerste benaderde termiese model van SUNSAT se batterye was die 7 gekonsentreerdemassa model wat gefokus het op die batterye aangesien daar vermoed is dat oorverhitting van die batterye die rede is waarom SUNSAT nie sy missie voltooi het nie. 'n Numeriese program so weI as 'n gelyksoortige TAS model is ontwikkel en die resultate korreleer tot binne 3°C. 'n Gekonsentreerde-massa model van SUNSA T is ook ontwikkel, numeries en met gebruik van TAS. Die modelle is getoets en die resultate toon dat die temperature van die modelle gevoelig is vir veranderinge in interne hitte sowel as vir wissellende uitstralingsvermoe en absorpsievermoe, Die numeriese- en die TAS gekonsentreerde-massa model resultate het nie goed met mekaar korrelleer nie, moontlik weens die hoe aantal kontrole volumes wat in die TAS gekonsentreerde-massa model gebruik is. Die TAS SUNSA T 2 model is 'n verdere ontwikkeling van die gekonsentreerde-massa model. Die hoer aantal kontrole volumes en die byvoeging van solarpanele het tot gevolg gehad dat hierdie 'n meer realistiese model van SUNSA T is. Die resultate het nie goed gekorrelleer met die temperatuurdata van die werklike SUNSAT nie, moontlik weens die feit dat die solarpanele nie op die bakwerk monteer is, soos in die geval van SUNSA T nie. Nietemin het het die TAS SUNSAT 2 model gelei tot die meer gevorderde TAS SUNSAT 3 model. Hierdie termiese model het die solarpaneel montuur ingesluit en het 'n hoer aantal kontrole volumes gehad, wat 'n beter fisiese weergawe van die SUNSAT subsisteme tot gevolg gehad het. Die model is getoets vir moontlike wentelbane van SUNSAT. Die resultate het 'n hoe korrellasie getoon met die data van die werklike SUNSAT. 'n Vergelyking van die TAS SUNSAT 3 model resultate met data van SUNSAT vir Julie 1999 wys dat die SUNSAT battery temperatuur dieselfde is tot binne 8°C. Vergelyk met die resultate vir Junie 2000 was dit binne 1°C. 'n Termiese bestuurs- en kontrolestudie is gedoen op 'n eenvoudige sisteem (insluitende 'n kubieke boks en 'n interne soliede blok met hitte opwekking) om die uitwerking van die gebruik van passiewe en aktiewe termiese kontrole hardeware wat temperature reguleer, te illustreer. Die resultate toon dat interne oppervlaktes wat swart geverf is, lei tot die maksimum hitte-deling, en die laagste bloktemperature. Daar is gevind dat bloktemperature baie gevoelig is vir veranderinge in die eienskappe van die kubus se eksterne optiese oppervlaktes. 'n Effense vermedering van uitstralingsvermoe verlaag die bloktemperatuur, terwyl 'n effense vermedering van absorpsievermoe die bloktemperatuur verhoog. Daar is ook gevind dat hittepype die temperatuur van die blok en onmiddelike subsisteme verlaag deur om 'n pad van lae termiese weerstand teen die vloei van hitte vanaf die blok, direk na die verkoeler te verskaf. Die uitwerking van termiese isolasie is ook ondersoek. In die geval van die twee materiale (rubber en plastiek) wat getoets is, is daar opgemerk dat, alhoewel isolasie materiaal meer termiese beheer oor die subsisteem en voorspelbaarheid tot gevolg gehad het deurdat die subsisteem termies van die omgewing isoleer is, kan dit veroorsaak dat die subsisteem te warm word. Aanbevelings is gemaak met betrekking tot toekomstige mikro satelliet bestuur en kontrole en wel in verband met die volgende: termiese modelleringstegnieke, die aanskaffing van getoetste sagteware, die plasing van temperatuut sensors vir die beste termiese data, en die verifikasie van die eienskappe van optiese oppervlaktes deur fisiese meting.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1983. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH / Includes bibliographical references (p. 69-70). / A prototype for a dwelling heat loss compensator is introduced in this thesis, along with its measured thermal performance and suggestions for its future development. As a heat loss compensator, the Sol-Clad-Siding collects, stores, and releases solar heat at room temperatures thereby maintaining a neutral skin for structures, which conserves energy, rather than attempting to supply heat into the interior as most solar systems do. Inhabitants' conventional objections to passive-solar systems utilized in housing are presented as a contrasting background. The potential of the outer component, a Trans-Lucent-Insulation as a sunlight diffuser and transmitter (65 to 52% of heating season insulation) and as a good insulator [0.62 W/(sq m) (°K) [0.11 Btu/(hr) (sq ft) (°F) 1] are described. The performance of the inner component, a container of phase-change materials as an efficient vertical thermal storage is discussed, and areas for future research are addressed. A very brief application of this passive-solar curtain wall system for dwellings is also given. / by Doru Iliesiu. / M.S.

Thesis (M.App.Sc.) - Carleton University, 2006. / Includes bibliographical references (p. 247-250). Also available in electronic format on the Internet.

Orientador: Kamal Abdel Radi Ismail / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica / Made available in DSpace on 2018-07-21T13:16:24Z (GMT). No. of bitstreams: 1 HenriquezGuerrero_JorgeRecarte_M.pdf: 22581929 bytes, checksum: 43baa03f4d321404f2af400b3968e721 (MD5) Previous issue date: 1996 / Resumo: Este trabalho apresenta uma abordagem diferente em relação ao conceito de janelas termicamente efetivas, isto é, janelas que reduzem a energia transmitida para dentro ou fora de uma sala. A idéia é usar um painel de vidro duplo preenchido com material de mudança de fase (pcm), cuja temperatura de fusão é determinada por critérios de conforto térmico. A investigação inclui modelamento dos mecanismo de transferência de calor e radiação através do painel, caracterização ótica de janelas convencionais e compostas, e simulação numérica. As amostras incluem vidros comerciais simples de diferentes espessuras e painéis de vidro duplo de diferentes espessuras e espaçamento entre vidros, preenchidos com ar, pcm e finalmente pcm colorido. O modelo é unidimensional transiente e a simulação numérica foi implementada através do método de diferenças finitas na sua forma explícita. Dos resultados da simulação numérica e dos testes de caracterização óticos foram levantadas curvas de ganho térmico, distribuição de temperatura através do painel e evolução da temperaturas da superfícies interna e externas do painel ao longo de um período de 24 horas de forma a verificar o efeito do pcm no desempenho térmico da janela composta / Abstract: This work present a new concept for thermally effective windows, that is windows which reduce the energy transfer to and fIom the internal ambient. This idea behind this concept is to use a pcm fill in the gap between the two glass panels. The fusion temperature of the pcm is selected according to the thermal cornfort criterion. The investigation includes modeling of the mechanisms of heat transfer relevant to the window problem, the thermal radiation through the glass panels, the optical characterization of conventional and composite window configurations and finally the numerical simulation of these configurations. Because of the lack of information on the thermal and optical properties of national gla~s and specially on the composite configuration optical tests were realized to determine the transmittance and reflectivity of simple glass panels of different thicknesses and spacings, air and pcm filled glass panels and finally coloured pcm filled glass panels. The model is a transient one dimensional and the numerical solution is based upon explicit finite difference scheme. the numerical simulations and the optical tests realized allow the determination of the heat gain, the temperature distribution across the glass panels, the outlet and the inlet instantaneous surface temperatures and finally the overall thermal performance of any glass panels including the proposed system / Mestrado / Termica e Fluidos / Mestre em Engenharia Mecânica