Готові списки джерел за темами / Commercial buildings Heating and ventilation Mathematical models

Зміст

Статті в журналах
Дисертації
Книги
Тези доповідей конференцій

Добірка наукової літератури з теми "Commercial buildings Heating and ventilation Mathematical models"

Автор: Grafiati

Опубліковано: 10 грудня 2022

Оновлено: 29 січня 2023

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Commercial buildings Heating and ventilation Mathematical models".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Статті в журналах з теми "Commercial buildings Heating and ventilation Mathematical models"

Szász, Cs. "Air-source heat pump LabView-based model development for NZEB applications." International Review of Applied Sciences and Engineering 5, no. 1 (June 1, 2014): 59–66. http://dx.doi.org/10.1556/irase.5.2014.1.8.

Повний текст джерела

Анотація:

Abstract A net zero-energy building (NZEB) is considered as a resident or commercial building where the energy needs are covered by using locally available renewable energy sources and technologies. Various types of heat pumps are widely used energy conversion systems for NZEB strategies implementation. This paper is focused on the development of a novel LabView-based model for an air-source heat pump system that absorbs heat from outside air and releases it inside the building as domestic hot water supply or room's space heating by using hot water-filled fan-coils. In the first research steps the mathematical background of the considered heat pump system has been developed. Then the LabView-based software implementation of the air-source heat pump and entire heating circuit model is unfolded and presented. The result is a versatile and powerful graphical software toolkit, suitable to simulate the complex heating, ventilation and air-conditioning processes in net-zero energy buildings and to perform energy balance performance evaluations. Beside the elaborated mathematical models, a concrete software implementation example and measurement data is provided in the paper. Last but not least, the proposed original model offers a feasible solution for future developments and research in NZEB applications modeling and simulation purposes.

Стилі APA, Harvard, Vancouver, ISO та ін.

Faddel, Samy, Guanyu Tian, and Qun Zhou. "Decentralized Management of Commercial HVAC Systems." Energies 14, no. 11 (May 24, 2021): 3024. http://dx.doi.org/10.3390/en14113024.

Повний текст джерела

Анотація:

With the growth of commercial building sizes, it is more beneficial to make them “smart” by controlling the schedule of the heating, ventilation, and air conditioning (HVAC) system adaptively. Single-building-based scheduling methods are more focused on individual interests and usually result in overlapped schedules that can cause voltage deviations in their microgrid. This paper proposes a decentralized management framework that is able to minimize the total electricity costs of a commercial microgrid and limit the voltage deviations. The proposed scheme is a two-level optimization where the lower level ensures the thermal comfort inside the buildings while the upper level consider system-wise constraints and costs. The decentralization of the framework is able to maintain the privacy of individual buildings. Multiple data-driven building models are developed and compared. The effect of the building modeling on the overall operation of coordinated buildings is discussed. The proposed framework is validated on a modified IEEE 13-bus system with different connected types of commercial buildings. The results show that coordinated optimization outperforms the commonly used commercial controller and individual optimization of buildings. The results also show that the total costs are greatly affected by the building modeling.

Стилі APA, Harvard, Vancouver, ISO та ін.

Junior, Moacir José Dalmina, Jair Antonio Cruz Siqueira, Carlos Eduardo Camargo Nogueira, Samuel Nelson Melegari de Souza, and Luciene Kazue Tokura. "Optimization of Energy Efficiency and Environmental Comfort in Broiler House." Journal of Agricultural Science 12, no. 10 (September 15, 2020): 162. http://dx.doi.org/10.5539/jas.v12n10p162.

Повний текст джерела

Анотація:

The objective of the study was to develop a design methodology involving a mixed system for better use of natural lighting and ventilation, together with electrical heating and ventilation systems that are currently used in commercial aviaries. Two building models were analyzed, one open conventional, and the other developed specifically for this study, with a cross ventilation brise-soleil system that provided greater energy efficiency in aviaries. Subsequently, the two models were compared using Autodesk’s Revit software through the Green Building Studio, to analyze the energy consumption of buildings during the year. The results showed that the model of poultry developed for the study proved to be more efficient in relation to the model of open poultry. The proposed broiler house was 21.07% more efficient than the conventional open aviary.

Стилі APA, Harvard, Vancouver, ISO та ін.

Baniyounes, Ali M., Yazeed Yasin Ghadi, Eyad Radwan, and Khalid S. Al-Olimat. "Functions of fuzzy logic based controllers used in smart building." International Journal of Electrical and Computer Engineering (IJECE) 12, no. 3 (June 1, 2022): 3061. http://dx.doi.org/10.11591/ijece.v12i3.pp3061-3071.

Повний текст джерела

Анотація:

<span>The main aim of this study is to support design and development processes of advanced fuzzy-logic-based controller for smart buildings e.g., heating, ventilation and air conditioning, heating, ventilation and air conditioning (HVAC) and indoor lighting control systems. Moreover, the proposed methodology can be used to assess systems energy and environmental performances, also compare energy usages of fuzzy control systems with the performances of conventional on/off and proportional integral derivative controller (PID). The main objective and purpose of using fuzzy-logic-based model and control is to precisely control indoor thermal comfort e.g., temperature, humidity, air quality, air velocity, thermal comfort, and energy balance. Moreover, this article present and highlight mathematical models of indoor temperature and humidity transfer matrix, uncertainties of users’ comfort preference set-points and a fuzzy algorithm.</span>

Стилі APA, Harvard, Vancouver, ISO та ін.

Liu, Shuailing, Guoyuan Ma, Xiaoya Jia, Shuxue Xu, and Guoqiang Wu. "Simulation research on heat recovery system of heat pump composite pump-driven loop heat pipe." Thermal Science, no. 00 (2022): 44. http://dx.doi.org/10.2298/tsci211119044l.

Повний текст джерела

Анотація:

To promote energy-saving potentials of the energy recovery unit under all-year conditions, a composite system combining pump-driven loop heat pipe with heat pump was firstly proposed, and the mathematical models were established. The operating characteristics of the composite system were studied in the whole year and compared with the traditional heat pump heat recovery system. The results show that the heating capacity of the composite system is in line with the heating load in winter. Compared with the traditional heat pump system, the composite system has higher energy efficiency ratio and lower deviation degree of temperature effectiveness in the whole year. The heat pump composite pump-driven loop heat pipe heat recovery system is generally superior to similar system reported in literatures, which indicates that it can replace heat pump system in buildings ventilation.

Стилі APA, Harvard, Vancouver, ISO та ін.

Pandey, Kamal, Bhaskar Basu, and Sandipan Karmakar. "An Efficient Decision-Making Approach for Short Term Indoor Room Temperature Forecasting in Smart Environment: Evidence from India." International Journal of Information Technology & Decision Making 20, no. 02 (March 2021): 733–74. http://dx.doi.org/10.1142/s0219622021500164.

Повний текст джерела

Анотація:

“Smart cities” start with “Smart Buildings” that improve the quality of urban services while ensuring sustainability. The current scenario in India reveals that the corporate and residential building structures are incorporating various self-sustainable techniques. Out of the multiple factors governing the comfort of smart buildings, indoor room temperature is an important one, since it drives the need of cooling or heating through controlling systems. Around one-third of total energy consumption of commercial buildings in India is attributed to Heating, Ventilation and Air Conditioning (HVAC) systems. Accurate prediction of indoor room temperature helps in creating an efficient equilibrium between energy consumption and comfort level of the building, thus providing opportunities for efficient decision making for energy optimization. Considering Indian climatic and geographical conditions, this paper proposes an efficient decision making approach using Bayesian Dynamic Models (BDM) for short-term indoor room temperature forecasting of a corporate building structure. The results obtained from Bayesian Dynamic linear model, using Expectation Maximization (EM) algorithm, have been compared to standard Auto Regressive Integrated Moving Average (ARIMA) model, and have been found to be more accurate. Forecasting of indoor room temperature is a highly nonlinear phenomenon, so to further improve the accuracy of the linear models, a hybrid modeling approach has been proposed. The inclusion of state-of-the-art nonlinear models such as Artificial Neural Networks (ANNs) and Support Vector Regression (SVR) improves the forecasting accuracy of the linear models significantly. Results show that the hybrid model obtained using BDM and ANN is the best fit model.

Стилі APA, Harvard, Vancouver, ISO та ін.

Katipamula, S., T. A. Reddy, and D. E. Claridge. "Multivariate Regression Modeling." Journal of Solar Energy Engineering 120, no. 3 (August 1, 1998): 177–84. http://dx.doi.org/10.1115/1.2888067.

Повний текст джерела

Анотація:

An empirical or regression modeling approach is simple to develop and easy to use compared to detailed hourly simulations of energy use in commercial buildings. Therefore, regression models developed from measured energy data are becoming an increasingly popular method for determining retrofit savings or identifying operational and maintenance (O&M) problems. Because energy consumption in large commercial buildings is a complex function of climatic conditions, building characteristics, building usage, system characteristics and type of heating, ventilation, and air conditioning (HVAC) equipment used, a multiple linear regression (MLR) model provides better accuracy than a single-variable model for modeling energy consumption. Also, when hourly monitored data are available, an issue which arises is what time resolution to adopt for regression models to be most accurate. This paper addresses both these topics. This paper reviews the literature on MLR models of building energy use, describes the methodology to develop MLR models, and highlights the usefulness of MLR models as baseline models and in detecting deviations in energy consumption resulting from major operational changes. The paper first develops the functional basis of cooling energy use for two commonly used HVAC systems: dual-duct constant volume (DDCV) and dual-duct variable air volume (DDVAV). Using these functional forms, the cooling energy consumption in five large commercial buildings located in central Texas were modeled at monthly, daily, hourly, and hour-of-day (HOD) time scales. Compared to the single-variable model (two-parameter model with outdoor dry-bulb as the only variable), MLR models showed a decrease in coefficient of variation (CV) between 10 percent to 60 percent, with an average decrease of about 33 percent, thus clearly indicating the superiority of MLR models. Although the models at the monthly time scale had higher coefficient of determination (R2) and lower CV than daily, hourly, and HOD models, the daily and HOD models proved more accurate at predicting cooling energy use.

Стилі APA, Harvard, Vancouver, ISO та ін.

Lazarevic, Sladjana, Velimir Congradac, Aleksandar Andjelkovic, Miroslav Kljajic, and Zeljko Kanovic. "District heating substation elements modeling for the development of the real-time model." Thermal Science 23, no. 3 Part B (2019): 2061–70. http://dx.doi.org/10.2298/tsci181226031l.

Повний текст джерела

Анотація:

In the heating system of residential and commercial buildings, heating substation has an important role because it is used as a separator between primary and secondary supply sides. In this paper, we focused on the development of the simulation model of all heating substation elements, which influence the change of relevant parameters: water temperature, flow, and pressure. The primary objective of the paper is to analyze and develop mathematical models of the heat exchanger, control valve, three-way valve and frequency-regulated centrifugal pump that are configurable and generic as much as possible, so they can be used for the development of the model that could operate in real time. A real-time model could be used as a suitable replacement for an actual physical system in the process of testing and improvement of the control system performance. Different elements setups of district heating substation are considered, and the modelbased simulation is presented for one of them.

Стилі APA, Harvard, Vancouver, ISO та ін.

Merabet, Ghezlane Halhoul, Mohamed Essaaidi, and Driss Benhaddou. "A dynamic model for human thermal comfort for smart building applications." Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering 234, no. 4 (July 28, 2019): 472–83. http://dx.doi.org/10.1177/0959651819865795.

Повний текст джерела

Анотація:

Thermal comfort is closely related to the evaluation of heating, ventilation, and air conditioning systems. It can be seen as the result of the perception of the occupants of a given environment, and it is the product of the interaction of a number of personal and environmental factors. Otherwise, comfort issues still do not play an important role in the daily operation of commercial buildings. However, in the workplace, local quality effects, in addition to the health, the productivity that has a significant impact on the performance of the activities. In this regard, researchers have conducted, for decades, investigations related to thermal comfort and indoor environments, which includes developing models and indices through experimentations to establish standards to evaluate comfort and factors and set-up parameters for heating, ventilation, and air conditioning systems. However, to our best knowledge, most of the research work reported in the literature deals only with parameters that are not dynamically tracked. This work aims to propose a prototype for comfort measuring through a wireless sensor network and then presenting a model for thermal comfort prediction. The developed model can be used to set up a heating, ventilation, and air conditioning system to meet the expected comfort level. In particular, the obtained results show that there is a strong correlation between users’ comfort and variables such as age, gender, and body mass index as a function of height and weight.

Стилі APA, Harvard, Vancouver, ISO та ін.

Yayla, Alperen, Kübra Sultan Świerczewska, Mahmut Kaya, Bahadır Karaca, Yusuf Arayıcı, Yunus Emre Ayözen, and Onur Behzat Tokdemir. "Artificial Intelligence (AI)-Based Occupant-Centric Heating Ventilation and Air Conditioning (HVAC) Control System for Multi-Zone Commercial Buildings." Sustainability 14, no. 23 (December 2, 2022): 16107. http://dx.doi.org/10.3390/su142316107.

Повний текст джерела

Анотація:

Buildings are responsible for almost half of the world’s energy consumption, and approximately 40% of total building energy is consumed by the heating ventilation and air conditioning (HVAC) system. The inability of traditional HVAC controllers to respond to sudden changes in occupancy and environmental conditions makes them energy inefficient. Despite the oversimplified building thermal response models and inexact occupancy sensors of traditional building automation systems, investigations into a more efficient and effective sensor-free control mechanism have remained entirely inadequate. This study aims to develop an artificial intelligence (AI)-based occupant-centric HVAC control mechanism for cooling that continually improves its knowledge to increase energy efficiency in a multi-zone commercial building. The study is carried out using two-year occupancy and environmental conditions data of a shopping mall in Istanbul, Turkey. The research model consists of three steps: prediction of hourly occupancy, development of a new HVAC control mechanism, and comparison of the traditional and AI-based control systems via simulation. After determining the attributions for occupancy in the mall, hourly occupancy prediction is made using real data and an artificial neural network (ANN). A sensor-free HVAC control algorithm is developed with the help of occupancy data obtained from the previous stage, building characteristics, and real-time weather forecast information. Finally, a comparison of traditional and AI-based HVAC control mechanisms is performed using IDA Indoor Climate and Energy (ICE) simulation software. The results show that applying AI for HVAC operation achieves savings of a minimum of 10% energy consumption while providing a better thermal comfort level to occupants. The findings of this study demonstrate that the proposed approach can be a very advantageous tool for sustainable development and also used as a standalone control mechanism as it improves.

Стилі APA, Harvard, Vancouver, ISO та ін.

Більше джерел

Дисертації з теми "Commercial buildings Heating and ventilation Mathematical models"

MacKinnon, Ian R. (Ian Roderick) 1964. "Air distribution from ventilation ducts." Thesis, McGill University, 1990. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59655.

Повний текст джерела

Анотація:

A wooden, perforated, uniform cross-section duct was examined to determine the optimum levels of aperture ratio and fan speed with respect to uniformity of discharge. The optimum aperture ratio for the 8.54 m long duct was 1.0 with a uniformity coefficient of 90.28%. The fan speed had little effect on the uniformity of discharge. The friction factor was experimentally determined to be 0.048 for a non-perforated duct and this value was assumed to be the same for a perforated duct of similar construction. A kinetic energy correction factor was used to analyze the flow in the duct. Values for this correction factor were determined from experimental data. Values of the coefficient of discharge and the total duct energy were calculated. A mathematical model was proposed based on the conservation of momentum and the Bernoulli's equation. The model responded favourably and predicted the duct velocity nearly perfectly and slightly underestimated the total duct energy.

Стилі APA, Harvard, Vancouver, ISO та ін.

Fu, Yan. "Modelling of ducted ventilation system in agricultural structures." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60519.

Повний текст джерела

Анотація:

Air distribution ducts are used in the environmental control of livestock and poultry building as well as the conditioning of most agricultural produce.
In order to simplify the approach to the design of ventilation ducts, a mathematical equation has been derived to describe the average air velocity of a duct.
The primary objective of the research work was to test goodness of fit of an equation describing the average air velocity of perforated ventilation ducts, under balanced as well as unbalanced air distribution: $V = H sb{o}{X over L} + (V sb{L}-H sb{o}) {X sp2 over L sp2}$.
This equation was successfully tested using data measured from 14 ducts of constant cross-sectional area, built of wood or polyethylene with outlets of various shapes and aperture ratios. Results indicated that aperture ratio and distance along the duct are the two most significant factors influencing the average duct air velocity values, but material and outlet shape had little effect.

Стилі APA, Harvard, Vancouver, ISO та ін.

Книги з теми "Commercial buildings Heating and ventilation Mathematical models"

Underwood, C. P. Modelling methods for energy in buildings. Oxford: Blackwell Science, 2004.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

H, Yik F. W., ed. Modelling methods for energy in buildings. Oxford: Blackwell Science, 2004.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Frech, G. Entwicklung numerischer Berechnungsverfahren von Schadstofferfassungseinrichtungen. Dortmund: Bundesanstalt für Arbeitsschutz, 1993.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Chapman, Kirby S. Develop simplified methodology to incorporate thermal comfort factors for temperature setback/setup into in-space heating and cooling design calculations: Final project report : research project 1114. [Atlanta, GA] : American Society of Heating, Refrigerating and Air-Conditioning Engineers, 1994.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Forest Products Laboratory (U.S.), ed. FPL roof temperature and moisture model: Description and verification. Madison, WI (One Gifford Pinchot Dr., Madison 53705-2398): U.S. Dept. of Agriculture, Forest Service, Forest Products Laboratory, 1997.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Underwood, Chris, and Francis Yik. Modelling Methods for Energy in Buildings. Wiley & Sons, Incorporated, John, 2008.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Yik, Francis, and C. P. Underwood. Modelling Methods for Energy in Buildings. Blackwell Publishing Limited, 2004.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Underwood, Chris, and Francis Yik. Modelling Methods for Energy in Buildings. Wiley & Sons, Incorporated, John, 2008.

Знайти повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Commercial buildings Heating and ventilation Mathematical models"

Endurthy, Akhilesh Reddy, and T. Agami Reddy. "A Screening Methodology for Climatic Evaluation of the Cooling Potential of Night Ventilation in Buildings." In ASME 2012 6th International Conference on Energy Sustainability collocated with the ASME 2012 10th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/es2012-91032.

Повний текст джерела

Анотація:

Night ventilation is a well known strategy for passive cooling of residences and small commercial buildings. The building’s thermal mass can be cooled at night by ventilating the inside of the space with the relatively lower outdoor air temperatures, thereby lowering indoor temperatures during the warmer daytime period. Numerous experimental and theoretical studies have shown the effectiveness of the method to significantly reduce air conditioning loads or improve comfort levels in those climates where the night time ambient air temperature drops below that of the indoor air. One could develop/adapt computer programs with detailed mathematical component models to simulate and evaluate the performance of night ventilation strategies in a specific location for a particular building. A more basic problem is to develop a methodology whereby potential designers can screen various climatic locations and regions in order to perform a preliminary evaluation of which months of the year are good candidates for implementing such a scheme. Only after completion of such a phase is a detailed evaluation warranted for specific buildings. In this paper, effectiveness of night ventilation is quantified by a parameter called the Discomfort Reduction Factor (DRF) which is the index of reduction of occupant discomfort levels during the day time from night ventilation. Two different thermal network models which provide such insights are evaluated. Daily and monthly DRFs are calculated for two climate zones and three building heat capacities for the whole year. It is verified that night ventilation is effective in seasons and regions when day temperatures are between 30 °C and 36 °C and night temperatures are below 20 °C. The accuracy of these preliminary screening models may be lower than using a detailed simulation program but the loss in accuracy in using such tools is more than compensated by the insights provided, along with better transparency in the analysis approach and results obtained.

Стилі APA, Harvard, Vancouver, ISO та ін.

McCurdy, Patrick J., Kaleb Pattawi, Chenli Wang, Thomas Roth, Cuong Nguyen, Yuhong Liu, and Hohyun Lee. "Validation Approach for Energy Optimization Models of Grid-Interactive Buildings Using Co-Simulation." In ASME 2021 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/imece2021-69679.

Повний текст джерела

Анотація:

Abstract The consumption and production of energy are more dynamic as distributed energy resources (DERs) such as solar photovoltaics (PV) are deployed within the electric distribution system. The existing techniques for bulk generation do not take full advantage of DERs and can lead to wasted energy and higher costs for both utility companies and consumers. Commercial and residential building energy management systems are usually on a fixed schedule and are not able to respond to changes in energy price instantaneously. There is a need for a real-time pricing structure that can accommodate the fluctuating cost of energy based on supply and demand, and for an energy management system that is able to respond to the dynamic utility rate. As such, there is a need for a robust energy management control strategy and methodology to validate new approaches. To address this gap, a strategy to control heating, ventilation, and air conditioning (HVAC) systems in a residential house was developed along with a validation methodology. A model of predictive control was implemented to optimize the thermostat setpoints and minimize energy cost for an individual residential house while maintaining thermal comfort of residents. This model was integrated with EnergyPlus simulation via an open source co-simulation platform previously developed at the National Institute of Standards and Technology (NIST). Total energy consumption and cost for consumers were compared between a case with the proposed model and a baseline case that used fixed-temperature setpoint control. The simple dynamic pricing model used in simulations was proportional to the demand of energy at that time of day. This work will contribute to the development of dynamic utility pricing models and residential control strategies for grid-interactive buildings and homes. The outcome of this research can be expanded to different building models or locations in future work.

Стилі APA, Harvard, Vancouver, ISO та ін.

Sankey, Maxim L., Sheldon M. Jeter, Trevor D. Wolf, Donald P. Alexander, Gregory M. Spiro, and Ben Mason. "Continuous Monitoring, Modeling, and Evaluation of Actual Building Energy Systems." In ASME 2014 8th International Conference on Energy Sustainability collocated with the ASME 2014 12th International Conference on Fuel Cell Science, Engineering and Technology. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/es2014-6610.

Повний текст джерела

Анотація:

Residential and commercial buildings account for more than 40% of U.S. energy consumption, most of which is related to heating, ventilation and air conditioning (HVAC). Consequently, energy conservation is important to building owners and to the economy generally. In this paper we describe a process under development to continuously evaluate a building’s heating and cooling energy performance in near real-time with a procedure we call Continuous Monitoring, Modeling, and Evaluation (CMME). The concept of CMME is to model the expected operation of a building energy system with actual weather and internal load data and then compare modeled energy consumption with actual energy consumption. For this paper we modeled two buildings on the Georgia Institute of Technology campus. After creating our building models, internal lighting loads and equipment plug-loads were collected through electrical sub-metering, while the building occupancy load was recorded using doorway mounted people counters. We also collected on site weather and solar radiation data. All internal loads were input into the models and simulated with the actual weather data. We evaluated the building’s overall performance by comparing the modeled heating and cooling energy consumption with the building’s actual heating and cooling energy consumption. Our results demonstrated generally acceptable energy performance for both buildings; nevertheless, certain specific energy inefficiencies were discovered and corrective actions are being taken. This experience shows that CMME is a practical procedure for improving the performance of actual well performing buildings. With improved techniques, we believe the CMME procedure could be fully automated and notify building owners in real-time of sub-optimal building performance.

Стилі APA, Harvard, Vancouver, ISO та ін.

Oosthuizen, Patrick H., and Marilyn Lightstone. "Use of CFD in the Analysis of Heat Transfer Related Problems That Arise in Building Energy Studies." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-23351.

Повний текст джерела

Анотація:

Energy simulation (ES) computer programs have been and still are widely used in the design and analysis of building energy systems. However, most ES programs assume that the air in the indoor building space is well mixed. As a result such programs cannot accurately predict building energy consumption for buildings with non-uniform air temperature distributions in the indoor space. They also cannot predict variations in thermal comfort levels in different parts of the building. Computational Fluid Dynamics (CFD), as a result, has become quite widely used in the design and evaluation of buildings energy systems in recent years. CFD can be used, for example, to predict the thermal comfort, natural lighting, natural ventilation, spread of smoke and contaminants in the building, and indoor air quality in a building. As a result it is proving to be an extremely valuable tool in the design of buildings and building systems. This, together with the fact that today’s commercial CFD software packages are relatively easy to use, has led to this quite widespread adoption of CFD methods in building energy analysis. Energy usage in buildings can be decreased by, for example, the use of daylighting (use of solar illumination in place of artificial lighting), by the use of natural ventilation, and by solar heating. CFD analysis provides a means of relatively accurately studying the effect of building design on the effectiveness of daylighting, natural ventilation, and solar heating. Another example of the use of CFD is in the study of the effect of various window blind arrangements on the building performance. In order for a CFD package to be used effectively in building energy analysis it should allow the use of a wide range of turbulence models, it should allow the incident solar radiation on the building to be found and used in the calculation of the indoor flow and temperature fields, it should allow the radiant heat exchange in the building to be incorporated into the calculation, and it should allow the effects of the thermal masses of the walls, floors, etc. to be easily incorporated into the calculation when they are deemed to be important. In this paper, the use of CFD methods in building energy analysis will be discussed as will some applications of CFD in building design. The use of CFD methods in developing design guidelines for particular types of buildings will also be briefly discussed.

Стилі APA, Harvard, Vancouver, ISO та ін.

Ratnanandan, Rajeevan, and Jorge E. González. "A System Modeling Approach for Active Solar Heating and Cooling System With Phase Change Material (PCM) for Small Buildings." In ASME 2012 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/imece2012-93038.

Повний текст джерела

Анотація:

The paper presents a study of the performance of an active solar thermal heating and cooling system for small buildings. The work is motivated by the need for finding sustainable alternatives for building applications that are climate adaptable. The energy demand for heating and cooling needs in residential and light commercial buildings in mid-latitudes represent more than 50% of the energy consumed annually by these buildings. Solar thermal energy represents an untapped opportunity to address this challenge with sustainable solutions. Direct heating could be a source for space heating and hot water, and for heat operated cooling systems to provide space cooling. However, a key limitation in mainstreaming solar thermal for heating and cooling has been the size of thermal storage to implement related technologies. We address this issue by coupling a Phase Change Material (PCM) with an adsorption chiller and a radiant flooring system for year round solar thermal energy utilization in Northern climates. The adsorption chiller allows for chill water production driven by low temperature solar thermal energy for summer cooling, and low temperature radiant heating provides for space heating in winter conditions, while hot water demand is supplied year round. These active systems are operated by high performance solar thermal collectors. The PCM has been selected to match temperatures requirements of the adsorption chiller, and the tank was designed to provide three levels of temperatures for all applications; cooling, heating, and hot water. The material selection is paraffin sandwiched with a graphite matrix to increase the conductivity. The specific objective of the preset work is to provide a system optimization of this active system. The system is represented by a series of mathematical models for each component; PCM tank with heat exchangers, the adsorption machine, the radiant floor, and the solar thermal collectors (Evacuated tubular collectors). The PCM modeling allows for sensible heating, phase change process, and superheating. Parametric simulations are conducted for a defined small building in different locations in US with the objective of defining design parameters for; optimal solar collector array, sizing of the PCM tank, and performance of the adsorption machine and radiant heating system. The monthly and annual solar fractions of the system are also reported.

Стилі APA, Harvard, Vancouver, ISO та ін.

Price, Christopher R., and Bryan P. Rasmussen. "Effective Tuning of Cascaded Control Loops for Nonlinear HVAC Systems." In ASME 2015 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/dscc2015-9806.

Повний текст джерела

Анотація:

Residential and commercial buildings are large consumers of energy in the United States with Heating, Ventilation, and Air-Conditioning (HVAC) systems representing a significant portion of total use. These systems control aspects such as humidity and room air temperature to ensure building occupant comfort. Control of HVAC units presents unique challenges due to large nonlinearities heavily dependent on operating conditions. Static linear controllers are unable to counteract such nonlinearities resulting in sustained oscillations known as hunting behavior. Previous research has shown the ability of cascaded architectures to compensate for HVAC nonlinearities and improve overall system performance without the need for detailed dynamic models. To aid the implementation of cascaded loops on real building systems, analysis of the effects of inner loop gain are presented and three outer loop tuning cases are identified. A simulation case study of an air handling unit demonstrates the simplicity of the procedure and compares it with optimally tuned gains.

Стилі APA, Harvard, Vancouver, ISO та ін.

Ми пропонуємо знижки на всі преміум-плани для авторів, чиї праці увійшли до тематичних добірок літератури. Зв'яжіться з нами, щоб отримати унікальний промокод!