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An Investigation of Alternative Methods for Measuring Static Pressure of Unitary Air Conditioners and Heat PumpsWheeler, Grant Benson 16 December 2013 (has links)
This project was created to address an important issue currently faced by test facilities measuring static pressure for air-conditioning and heat pumps. Specifically, ASHRAE Standard 37, the industry standard for test setup, requires an outlet duct of a certain length, based on the unit outlet geometry, and this ducting added to the unit height may result in a test apparatus height that exceeds psychometric test room dimensions. This project attempted to alter the outlet duct in a way that reduces the test apparatus height while maintaining the reliability of the ASHRAE Standard 37 testing setup. The investigation was done in two scenarios, the first, which altered the direction of the flow after the unit with an elbow and measured static pressure downstream of the elbow, and the second which inserted a passive resistive piece in the flow to decrease the required distance between the unit and the static pressure measurement. Three air handling units were used in Scenario 1 and Scenario 2 testing, with the two smallest units additionally being tested in Scenario 1 with an over-sized duct. The scenario tests were required to be within 5% power and 2.5% airflow of a baseline test following ASHRAE Standard 37.
he results for Scenario 1 have shown that ASHRAE Standard 37 can be modified to reduce testing height restrictions by using a square elbow with turning vanes, provided it is oriented in a specific way in relation to the blower. Furthermore, additional Scenario 1 testing on the over-sized outlet duct shows that possibilities exist for using a single over-sized duct to successfully meet ASHRAE Standard 37 testing conditions when testing a variety of units. Finally, the results of Scenario 2 have shown that the height constraints of the outlet duct can be reduced by installing a passive resistive device consisting of a mesh at the outlet; however, this approach applies only to those units with the heat exchanger located downstream of the blower. As a result of specific issues or problems that were encountered during the project that were beyond the scope, eleven case studies were presented and recommended for future work.
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Study to Find Out the Optimum Number of Transparent Covers and Refractive Index for the Best Performance of Sunearth Solar Water Heater Using Matlab SoftwareJanuary 2015 (has links)
abstract: Research was conducted to observe the effect of Number of Transparent Covers and Refractive Index on performance of a domestic Solar Water heating system. The enhancement of efficiency for solar thermal system is an emerging challenge. The knowledge gained from this research will enable to optimize the number of transparent covers and refractive index prior to develop a solar water heater with improved optical efficiency and thermal efficiency for the collector. Numerical simulation is conducted on the performance of the liquid flat plate collector for July 21st and October 21st from 8 am to 4 pm with different refractive index values 1.1, 1.4, 1.7 and different numbers of transparent covers (0-3). In order to accomplish the proposed method the formulation and solutions are executed using simple software MATLAB. The result demonstrates efficiency of flat plate collector increases with the increase of number of covers. The performance of collector decreases when refractive index is higher. The improved useful heat gain is obtained when number of cover used is 3 and refractive index is 1.1. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2015
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Advantages of Using the ANSI/ASHRAE 110-1995 Tracer Gas Test Method Versus the ANSI/AIHA Z9.5-1992 Face Velocity Test Method for Chemical Laboratory Hood CertificationFahim, Mahdi H. 14 April 2007 (has links)
No description available.
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Determining the effects of duct fittings on volumetric air flow measurementsHickman, Craig January 1900 (has links)
Master of Science / Department of Mechanical and Nuclear Engineering / B. Terry Beck / The purpose of the research was to quantify the influence of several duct disturbances on volumetric flow rate measurements and use these in developing guidelines for field technicians. This will assist the field technicians in making more accurate volumetric air flow measurements in rectangular ducts during a test and balance operation.
Multiple duct sizes, fittings, probes, traverse algorithms, and locations upstream and downstream of the disturbances are used to compare a variety of situations. The two traverse algorithms used are the log-Tchebycheff and equal area methods. Two upstream and five downstream locations are tested for each duct configuration. Two air velocity probes are used for local velocity measurements on each traverse: a pitot-static probe and a hot wire anemometer. A nozzle bank and Air Flow Measurement Station are used as the flow measurement standards for comparison with each traverse.
This paper discusses the setup and initial results of ASHRAE 1245-RP. Data collected subsequent to this thesis will complete the balance of results and will be collected and analyzed by other researchers. Results will be summarized and presented in a way which allows technicians to use it in the field for more accurate balancing results.
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Psychrometric Testing Facility Restoration and Cooling Capacity TestingCline, Vincent E. 2010 August 1900 (has links)
The Psychrometric Testing Facility at the Riverside Energy Efficiency Laboratory at Texas AandM University has not been operational for several years. The goal of this project was to restore the testing facility to a fully operational condition for the purpose of supporting research and cooling capacity testing, with the latter following the appropriate standards.
Numerous changes were made to the coolant piping system, the data acquisition system, instrumentation, and temperature and humidity control to update and improve the facility. In addition, a computer program was developed and implemented that allows for flexible control of the facility’s conditions and collection of data while showing real time performance and refrigerant and psychrometric calculations. The current program flexibility, along with the proper combination of instrumentation, allows the Psychrometric Facility to operate with separate steady state environmental conditions in each room, according to, and meeting, the AHRI 210/240 standard.
Cooling capacity testing done on a split system residential unit was compared to the published AHRI rating to benchmark the state of the facility. Tested cooling capacity was about 3 percent below the published cooling capacity; tested EER was about 7 percent below the published EER; and finally, the calculated SEER based on the default degradation coefficient was about 10 percent below the published SEER. The difference in the calculated performance parameters to the published are expected due to unknown testing conditions used to calculate the published rating.
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Avaliação do conforto térmico de uma biblioteca universitária pela ASHRAE Standard 55 e EN 15251 / Analysis of the thermal ambience of the universitarian library by ASHRAE Standard 55 and EN 15251Valadão, Júlia Barros 29 September 2011 (has links)
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Previous issue date: 2011-09-29 / Since 2001 energy crisis, Brazil searches to rationalize it's energetic usage, one of the objects used to reach this goal is the creation of minimum level of energetic efficiency. This process, first initiated in 2009 with electric appliances, has reached a new status when included buildings in the Programa Brasileiro de Etiquetagem (Brazilian Tagging Program), as can be verified in Regulamento Técnico da Qualidade do Nível de Eficiência Energética de Edifício Comerciais de Serviços Públicos [Technical Norm of Energetic Efficiency Level in Commercial, Services and Public Buildings] (RTQ-C). Although RTQ-C allows the measurement of efficiency levels in buildings, it does not guarantee the higrothermal comfort levels, because it remains silent about this subject, thus maintaining the national tradition of inexistent norms in this area. Begining with the exposed facts, this study objectives were to compare higrothermal comfort levels between ANSI/ASHRAE Standard 55, ISO 7730 and
15251 norms, through a case study using the Biblioteca Central of Universidade Federal de Viçosa-MG, pointing out the differences in those norms. The research was performed in four different stages: in loco measurements of the building in three separate seasons of the year, in order to collect higrothermal conditions in summer, autumn and winter; the pre-modeling tests, which verified the possibility of simplification of the library modeling in order to keep, while in simulation, higrothermal conditions similar to those in the real building; the validation of the model through simulations, which had alterations in parameters of the reference archetype, comparing the exiting data to the ones measured in the place in a way to approach environmental manifestation found in the real building; at last it was defined a level scale of thermal comfort, that made possible the comparison between the different norms. The main results obtained, in this research: a) not occur on the premises considered, the environments in conditions that meet the human needs of comfort and hygrothermal conservation bibliographic b) realization of the possibility of use in Brazil, comfort scale for assessment of proposed buildings, existing in EN 15251, therefore, to be more restrictive would allow the improvement of the quality of buildings in this regard. / Desde a crise de energia de 2001, o Brasil busca racionalizar o seu consumo energético, utilizando, como um dos instrumentos para atingir essa finalidade, a criação de níveis mínimos de eficiência energética. Esse processo, iniciado com os eletrodomésticos, galgou novo patamar ao incluir as edificações no Programa Brasileiro de Etiquetagem, em 2009, conforme se verifica pelo Regulamento Técnico da Qualidade do Nível de Eficiência Energética de Edifícios Comerciais de Serviços e Públicos (RTQ-C). Embora o RTQ-C permita que se mensure o nível de eficiência das edificações, não garante os índices de conforto higrotérmico, já que silente nesse aspecto, mantendo-se, assim, a tradição nacional de inexistência de regulamentação nessa matéria. Partindo desses fatos, o presente estudo objetivou comparar os níveis de conforto higrotérmico entre as normas ANSI/ASHRAE Standard 55 e EN 15251, tendo como estudo de caso a Biblioteca Central da Universidade Federal de Viçosa-MG, apontando as diferenças entre os seus resultados. A pesquisa foi realizada em quatro etapas principais: a realização de medições in loco da edificação em três épocas do ano, para coleta das condições higrotérmicas de verão, outono e inverno; a realização dos testes pré-modelagem, em que se verificou a possibilidade de simplificação da modelagem da biblioteca para manter, na simulação, condições higrotérmicas semelhantes ao edifício real; a validação do modelo mediante simulações em que se alteraram parâmetros no arquétipo referência, comparando-se os dados de saída aos medidos no local, de forma a se aproximar das manifestações ambientais encontradas no edifício real; e, finalmente, definição de uma escala de níveis de conforto térmico, o que viabilizou a comparação entre as normas. Como principais resultados obtidos, tem-se: a) não ocorrência, no edifício analisado, de ambientes em condições que satisfazem as necessidades humanas de conforto higrotérmico e as de conservação do acervo bibliográfico; b) constatação da possibilidade de uso, no Brasil, da escala de conforto proposta para avaliação das edificações, existente na EN 15251, pois, por ser mais restritiva, viabilizaria a melhoria da qualidade das construções neste aspecto.
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Impact of ASHRAE standard 189.1-2009 on building energy efficiency and performanceBlush, Aaron January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Fred L. Hasler / The purpose of this report is to provide an introduction to the new ASHRAE Standard 189.1-2009, Standard for the Design of High-Performance Green Buildings. The report will include an overview of the standard to detail what the purpose, scope and requirements for high-performance buildings will be. The entire standard will be overviewed, but the focus of this paper is in the areas of energy efficiency and building performance. Next, the report will examine further impacts that the standard will have on the building design and construction industry. Chapter 3 includes the impact on other standards, specification writing and coordination of the design and construction teams. A case study of an office building is performed to compare a baseline building meeting ASHRAE Standard 90.1 to a building meeting the minimum standards of ASHRAE Standard 189.1. The case study compares the total annual energy use of the two projects to determine an expected energy savings. Based on this information, recommendations about the new standard will be discussed. Universities and government entities should require ASHRAE Standard 189.1 for new construction projects, to show willingness to provide sustainability in buildings. Finally, conclusions about how the standard will change and impact industry will be addressed. These conclusions will include issues with adopting ASHRAE Standard 189.1 as code as well as discussion on the LEED rating system.
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An energy consumption evaluation for existing, commercial buildingsDamron, Lauren Leigh Brannom January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Julia A. Keen / The intent of this report is to recommend a process for legislation that can be used to identify commercial buildings that have the greatest potential to reduce energy consumption. A point-based evaluation is completed of current energy processes for existing commercial buildings. The recommended energy evaluation system is applied to an existing building, which allows for a detailed review of how the evaluation is completed for a building. The results are presented to display the value of assessing building energy performance. Additionally, the results reinforce the potential to transform the industry and energy use by buildings.
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The development and critical evaluation of learner thermal comfort protocol for applicability to two primary schools in Mamelodi, City of TshwaneMotsatsi, Lorato January 2015 (has links)
The purpose of this study is to develop a Learner Thermal Comfort Protocol (LTCP) for the assessment of thermal comfort in naturally ventilated public school classrooms occupied by primary learners aged between 7 and 14 years and to establish whether there is a relationship between the thermal comfort standards (ASHRAE 55-2004 and ISO 7730-2005) and the learners’ perception thereof.
The study tests the LTCP on two primary school case studies in Mamelodi Township, City of Tshwane (CoT), South Africa, by following the adaptive or field study method to collect quantitative data from the classroom and the learners. The classrooms’ actual temperature is measured and recorded by HOBO pendant data loggers while the learners’ thermal comfort perception is surveyed using questionnaires. The actual classroom indoor temperatures are compared to the ASHRAE 55 and ISO 7730 standard temperature range recommendations of ±22°C to ±27°C, based on the heat balance model, and ±20°C to ±27°C temperature range based on the context related adaptive model.
To establish whether there is a relationship between standards and learners’ perception, the learners’ perception results are compared to the predicted percentage that occupants would find acceptable.
This predicted percentage is based on the heat balance model (i.e. 80%) and adaptive model (i.e. 80% - 90%).
The results indicate that the indoor temperature range did not meet the recommended temperature range of either of the thermal comfort models. However, the thermal perception scale shows that the indoor temperatures were accepted by most of the learners. A relationship between the learners’ perception, the thermal comfort standards’ recommended temperature range and predicted percentage of acceptance was established. However, a wider temperature range is suggested for the thermal comfort assessment of classrooms located in the South African climate.
This study will contribute to the body of knowledge on thermal comfort in schools and provide the Department of Basic Education (DBE) with an assessment tool for the evaluation of school classroom indoor environments. / Dissertation (MArch(Prof)--University of Pretoria, 2015. / Architecture / Unrestricted
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Recommended Modified zone Method Correction Factor for Determining R-values of Cold-Formed Steel Wall AssembliesBlack, John 05 1900 (has links)
Currently, ASHRAE has determined the zone method and modified zone method are appropriate calculation methods for materials with a high difference in conductivity, such as cold-formed steel (CFS) walls. Because there is currently no standard U-Factor calculation method for CFS walls, designers and code officials alike tend to resort to the zone method. However, the zone method is restricted to larger span assemblies because the zone factor coefficient is 2.0. This tends to overestimate the amount of surface area influenced by CFS. The modified zone method is restricted to C-shaped stud, clear wall assemblies with framing factors between 9 and 15%. The objective of the research is to narrow the gap of knowledge by re-examining the modified zone method in order to more accurately determine R-Values and U-Factors for CFS wall assemblies with whole wall framing factor percentages of 22% and above.
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