Download or read book Indoor and Outdoor Radiant Cooling Systems for Buildings written by Ardeshir Moftakhari and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heating, Ventilation and Air Conditioning (HVAC) systems account for a major portion of overall energy consumption in buildings. Most HVAC systems use conventional and well established all-air thermal distribution systems that rely on convection as the major heat transfer mechanism for heat extraction. However, energy conservation efforts encouraged research related to radiant systems that can improve efficiency of HVAC systems. Radiant systems can be integrated into the building envelope by means of radiant cooling panels or slabs. These systems can increase the efficiency of the HVAC system by allowing chillers to operate more efficiently at a higher chilled water temperature compared to all-air systems. Another example of using radiative heat transfer for energy efficiency is in systems that use exterior spectrally-selective surfaces to intensively radiate heat to the outer space under suitable atmospheric conditions or passive radiative cooling (PRC). These systems utilize materials with high albedo coating and emit thermal infrared radiation that exploits the atmospheric window, resulting in sub-ambient surface temperatures, even during sunny days. Both indoor and outdoor radiant cooling systems need further development before they show full potential for increasing building energy efficiency. However, there are many questions about these systems that need to be addressed. For indoor radiant cooling systems, there is no clearly defined design process. Currently, design relies on procedures developed for all air systems, which in some situations are systems that cannot deliver the load when considering effective control of indoor environmental conditions. Also, there is a need for better understanding of the dynamics of heat transfer in rooms with radiant cooling systems and inclusion of this into the design procedure. When considering novel outdoor radiant cooling systems, all engineering aspects of these systems are very much unknown as these systems just emerged and there are few full-scale prototypes. From the theoretical studies (Zhu et al., 2013), we know that these PRC systems that are based on selective surfaces can produce cooling power of up to 100 (W/m2); however, there is little to no information how ambient condition, application specifics, and material affects performance of these systems. Additionally, there are no models associated with selective PRC films that can be implemented in the design or energy performance modeling tools. My PhD thesis work utilizes the state-of-the-art facilities, such as Thermal Façade lab and Roof Testing lab at the University of Texas at Austin, to conduct a set of full-scale experiments and combine experimental results with analytical and numerical modeling to address several research and engineering challenges related to the system design process, operation and energy performance. Specifically, my dissertation: (a) investigates the complex heat transfer dynamics of spaces conditioned with radiant cooling panels, (b) develops a system design that integrates building thermal response to these radiant cooling systems, (c) advances the system control strategy by integrating all influencing parameters in the model that provides optimal thermal comfort and energy saving, (d) evaluates thermal performance of PRC-based roofs in a full-scale prototype, and (e) develops sky radiation models for energy analysis of the PRC-based roofing technology. The research builds upon fundamental science and principles while the findings are incorporated in the ASHRAE and other relevant building design guidelines used worldwide by HVAC designers and practitioners

Download or read book Radiant Cooling in US Office Buildings written by Corina Stetiu and published by . This book was released on 1997 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Control of Hydronic Radiant Cooling Systems written by Jingjuan Feng and published by . This book was released on 2014 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Improving energy efficiency in the Heating Ventilation and Air conditioning (HVAC) systems in buildings is critical to achieve the energy reduction in the building sector, which consumes 41% of all primary energy produced in the United States, and was responsible for nearly half of U.S. CO2 emissions. Based on a report by the New Building Institute (NBI), when HVAC systems are used, about half of the zero net energy (ZNE) buildings report using a radiant cooling/heating system, often in conjunction with ground source heat pumps. Radiant systems differ from air systems in the main heat transfer mechanism used to remove heat from a space, and in their control characteristics when responding to changes in control signals and room thermal conditions. This dissertation investigates three related design and control topics: cooling load calculations, cooling capacity estimation, and control for the heavyweight radiant systems. These three issues are fundamental to the development of accurate design/modeling tools, relevant performance testing methods, and ultimately the realization of the potential energy benefits of radiant systems. Cooling load calculations are a crucial step in designing any HVAC system. In the current standards, cooling load is defined and calculated independent of HVAC system type. In this dissertation, I present research evidence that sensible zone cooling loads for radiant systems are different from cooling loads for traditional air systems. Energy simulations, in EnergyPlus, and laboratory experiments were conducted to investigate the heat transfer dynamics in spaces conditioned by radiant and air systems. The results show that the magnitude of the cooling load difference between the two systems ranges from 7-85%, and radiant systems remove heat faster than air systems. For the experimental tested conditions, 75-82% of total heat gain was removed by radiant system during the period when the heater (simulating the heat gain) was on, while for air system, 61-63% were removed. From a heat transfer perspective, the differences are mainly because the chilled surfaces directly remove part of the radiant heat gains from a zone, thereby bypassing the time-delay effect caused by the interaction of radiant heat gain with non-active thermal mass in air systems. The major conclusions based on these findings are: 1) there are important limitations in the definition of cooling load for a mixing air system described in Chapter 18 of ASHRAE Handbook of Fundamentals when applied to radiant systems; 2) due to the obvious mismatch between how radiant heat transfer is handled in traditional cooling load calculation methods compared to its central role in radiant cooling systems, this dissertation provides improvements for the current cooling load calculation method based on the Heat Balance procedure. The Radiant Time Series method is not appropriate for radiant system applications. The findings also directly apply to the selection of space heat transfer modeling algorithms that are part of all energy modeling software. Cooling capacity estimation is another critical step in a design project. The above mentioned findings and a review of the existing methods indicates that current radiant system cooling capacity estimation methods fail to take into account incident shortwave radiation generated by solar and lighting in the calculation process. This causes a significant underestimation (up to 150% for some instances) of floor cooling capacity when solar load is dominant. Building performance simulations were conducted to verify this hypothesis and quantify the impacts of solar for different design scenarios. A new simplified method was proposed to improve the predictability of the method described in ISO 11855 when solar radiation is present. The dissertation also compares the energy and comfort benefits of the model-based predictive control (MPC) method with a fine-tuned heuristic control method when applied to a heavyweight embedded surface system. A first order dynamic model of a radiant slab system was developed for implementation in model predictive controllers. A calibrated EnergyPlus model of a typical office building in California was used as a testbed for the comparison. The results indicated that MPC is able to reduce the cooling tower energy consumption by 55% and pumping power consumption by 26%, while maintaining equivalent or even better thermal comfort conditions. In summary, the dissertation work has: (1) provided clear evidence that the fundamental heat transfer mechanisms differ between radiant and air systems. These findings have important implications for the development of accurate and reliable design and energy simulation tools; (2) developed practical design methods and guidance to aid practicing engineers who are designing radiant systems; and (3) outlined future research and design tools need to advance the state-of-knowledge and design and operating guidelines for radiant systems.

Download or read book Radiant Heating and Cooling Handbook written by Richard D. Watson and published by McGraw-Hill Professional Publishing. This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Packed with tools to make the work of HVAC systems designers; engineers; and technicians go smoothly; this text will help you select; design; size; and position popular and efficient systems for industrial; commercial; and residential applications. --

Download or read book Thermal Comfort and Energy Efficient Cooling of Nonresidential Buildings written by Doreen E. Kalz and published by Springer Science & Business Media. This book was released on 2014-03-26 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book supports HVAC planners in reducing the cooling energy demand, improving the indoor environment and designing more cost-effective building concepts. High performance buildings have shown that it is possible to go clearly beyond the energy requirements of existing legislation and obtaining good thermal comfort. However, there is still a strong uncertainty in day-to-day practice due to the lack of legislative regulations for mixed-mode buildings which are neither only naturally ventilated nor fully air-conditioned, but use a mix of different low-energy cooling techniques. Based on the findings from monitoring campaigns (long-term measurements in combination with field studies on thermal comfort), simulation studies, and a comprehensive review on existing standards and guidelines, this book acts as a commonly accessible knowledge pool for passive and low-energy cooling techniques.

Download or read book Mastering Hydronic HVAC Systems written by Charles Nehme and published by Charles Nehme. This book was released on with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt: Welcome to the world of HVAC hydronic systems, where the marriage of heating, ventilation, and air conditioning meets the elegance and efficiency of water-based heating and cooling solutions. This book is an exploration of the principles, design, and applications of hydronic systems in the context of HVAC. As the demand for energy-efficient and environmentally friendly solutions continues to grow, hydronic systems have emerged as a preferred choice for heating and cooling residential, commercial, and industrial spaces. These systems leverage the unique properties of water as a medium for transferring thermal energy, offering numerous advantages over traditional air-based HVAC systems. The aim of this book is to provide a comprehensive and accessible resource for understanding the fundamentals of hydronic systems, their components, and their integration into building infrastructure. Whether you are a seasoned HVAC professional seeking to expand your knowledge or a student entering the field, this book will serve as a valuable guide. In the chapters that follow, we will delve into the key principles underlying hydronic systems, exploring topics such as fluid dynamics, heat transfer, system components, control strategies, and system design considerations. We will discuss various types of hydronic heating and cooling systems, including radiant floor heating, chilled beam systems, and fan coil units, highlighting their unique features and applications. Additionally, we will examine the role of pumps, boilers, heat exchangers, valves, and other essential components in hydronic systems. We will explore the intricacies of system balancing, zoning, and control, emphasizing the importance of proper installation, operation, and maintenance practices to ensure optimal system performance and energy efficiency. Throughout this book, we will also address emerging trends and technologies in the field of HVAC hydronic systems, such as advanced control algorithms, renewable energy integration, and smart building automation. By staying informed about these developments, you will be equipped to navigate the evolving landscape of HVAC engineering. It is my hope that this book will serve as a source of inspiration, knowledge, and practical guidance for those involved in the design, installation, and operation of HVAC hydronic systems. By harnessing the power of water and embracing the principles outlined in these pages, we can create comfortable and sustainable indoor environments for generations to come. Remember, this book is a starting point—a foundation upon which you can build your understanding and expertise. So, let us embark on this journey together, exploring the world of HVAC hydronic systems and discovering the boundless possibilities they offer. Charles Nehme

Download or read book Low Temperature Heating and High Temperature Cooling written by Jan Babiak and published by . This book was released on 2013 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Passive Cooling of Buildings written by D. Asimakopoulos and published by Routledge. This book was released on 2013-10-31 with total page 494 pages. Available in PDF, EPUB and Kindle. Book excerpt: Energy use in buildings in the EU represents about 40% of the total annual energy consumption. With greater awareness of the need to reduce energy consumption comes a growth of interest in passive cooling, particularly as an alternative to air-conditioning. This book describes the fundamentals of passive cooling together with the principles and formulae necessary for its successful implementation. The material is comprised largely of information and results compiled under the SAVE European Research Programme.

Download or read book Simulation of Radiant Cooling Performance with Evaporative Cooling Sources written by Timothy Charles Moore and published by . This book was released on 2008 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Thermal Comfort Analysis and Applications in Environmental Engineering written by P. O. Fanger and published by McGraw-Hill Companies. This book was released on 1970 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Desiccant Assisted Cooling written by Carlos Eduardo Leme Nóbrega and published by Springer Science & Business Media. This book was released on 2013-11-19 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: The increasing concern with indoor air quality has led to air-quality standards with increased ventilation rates. Although increasing the volume flow rate of outside air is advisable from the perspective of air-quality, it is detrimental to energy consumption, since the outside air has to be brought to the comfort condition before it is insufflated to the conditioned ambient. Moreover, the humidity load carried within outside air has challenging HVAC engineers to design cooling units which are able to satisfactorily handle both sensible and latent contributions to the thermal load. This constitutes a favorable scenario for the use of solid desiccants to assist the cooling units. In fact, desiccant wheels have been increasingly applied by HVAC designers, allowing distinct processes for the air cooling and dehumidification. In fact, the ability of solid desiccants in moisture removal is effective enough to allow the use of evaporative coolers, in opposition to the traditional vapor-compression cycle, resulting in an ecologically sound system which uses only water as the refrigerant. Desiccant Assisted Cooling: Fundamentals and Applications presents different approaches to the mathematical modeling and simulation of desiccant wheels, as well as applications in thermal comfort and humidity controlled environments. Experts in the field discuss topics from enthalpy, lumped models for heat and mass transfer, and desiccant assisted radiant cooling systems, among others. Aimed at air-conditioning engineers and thermal engineering researchers, this book can also be used by graduate level students and lecturers in the field.

Download or read book Heating and Cooling of Buildings written by Jan F. Kreider and published by CRC Press. This book was released on 2009-12-28 with total page 866 pages. Available in PDF, EPUB and Kindle. Book excerpt: The art and the science of building systems design evolve continuously as designers, practitioners, and researchers all endeavor to improve the performance of buildings and the comfort and productivity of their occupants. Retaining coverage from the original second edition while updating the information in electronic form, Heating and Cooling of Buildings: Design for Efficiency, Revised Second Edition presents the technical basis for designing the lighting and mechanical systems of buildings. Along with numerous homework problems, the revised second edition offers a full chapter on economic analysis and optimization, new heating and cooling load procedures and databases, and simplified procedures for ground coupled heat transfer calculations. The accompanying CD-ROM contains an updated version of the Heating and Cooling of Buildings (HCB) software program as well as electronic appendices that include over 1,000 tables in HTML format that can be searched by major categories, a table list, or an index of topics. Ancillary information is available on the book’s website www.hcbcentral.com From materials to computers, this edition explores the latest technologies exerting a profound effect on the design and operation of buildings. Emphasizing design optimization and critical thinking, the book continues to be the ultimate resource for understanding energy use in buildings.

Download or read book Radiant Cooling in US Office Buildings written by and published by . This book was released on 1998 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: Much attention is being given to improving the efficiency of air-conditioning systems through the promotion of more efficient cooling technologies. One such alternative, radiant cooling, is the subject of this thesis. Performance information from Western European buildings equipped with radiant cooling systems indicates that these systems not only reduce the building energy consumption but also provide additional economic and comfort-related benefits. Their potential in other markets such as the US has been largely overlooked due to lack of practical demonstration, and to the absence of simulation tools capable of predicting system performance in different climates. This thesis describes the development of RADCOOL, a simulation tool that models thermal and moisture-related effects in spaces equipped with radiant cooling systems. The thesis then conducts the first in-depth investigation of the climate-related aspects of the performance of radiant cooling systems in office buildings. The results of the investigation show that a building equipped with a radiant cooling system can be operated in any US climate with small risk of condensation. For the office space examined in the thesis, employing a radiant cooling system instead of a traditional all-air system can save on average 30% of the energy consumption and 27% of the peak power demand due to space conditioning. The savings potential is climate-dependent, and is larger in retrofitted buildings than in new construction. This thesis demonstrates the high performance potential of radiant cooling systems across a broad range of US climates. It further discusses the economics governing the US air-conditioning market and identifies the type of policy interventions and other measures that could encourage the adoption of radiant cooling in this market.

Download or read book Advances in Passive Cooling written by Mat Santamouris and published by Earthscan. This book was released on 2012-05-16 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following a rapid increase in the use of air conditioning in buildings of all types, the energy demand for powering such devices has become a significant cause for concern. Passive cooling is increasingly being thought of as the best alternative to air conditioning.This book offers the latest knowledge and techniques on passive cooling, enabling building professionals to understand the state of the art and employ relevant new strategies. With separate chapters on comfort, urban microclimate, solar control, ventilation, ground cooling and evaporative and radiative cooling, this authoritative text will also be invaluable for architects, engineers and students working on building physics and low-energy design.Advances in Passive Cooling is part of the BEST series, edited by Mat Santamouris. The aim of the series is to present the most current, high quality theoretical and application oriented material in the field of solar energy and energy efficient buildings. Leading international experts cover the strategies and technologies that form the basis of high-performance, sustainable buildings, crucial to enhancing our built and urban environment.

Download or read book Climatic Design written by Donald Watson and published by McGraw-Hill Companies. This book was released on 1983 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: An updated paperback re-issue of the guide to energy-efficient building design based on local climate. Table of Contents--Introduction; Part I: Principles (1) Heat and People; (2) Comfort and Indoor Climate; (3) Strategies of Climate Control; (4) Promote Solar Gain; (5) Minimize Conductive Heat Flow; (6) Minimize Infiltration; (7) Minimize Solar Gain; (8) Promote Ventilation; (9) Promote Radiant Cooling; (10) Promote Evaporative Cooling - Roof Systems; (11) Promote Conductive Cooling; (12) Appendices; Part II: Practices; Part III: Climatic Data; Part IV: Bibliography. Index. 285 illustrations.

Download or read book Audel HVAC Fundamentals Volume 3 written by James E. Brumbaugh and published by John Wiley & Sons. This book was released on 2011-01-31 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: Keep it cool or heat things up This third volume of Audel's HVAC Library gives you a comprehensive, hands-on guide to installing, servicing, and repairing all basic air-conditioning systems in both new and older construction. You'll also find complete coverage of specialized heating units-radiators, radiant heating systems, stoves, fireplaces, heat pumps, and indoor/outdoor pool heaters, plus fans, exhaust systems, air filters, and more. It's what you need to complete your HVAC reference library. * Make accurate calculations for AC system output * Tailor AC systems for older construction * Learn to install and service today's popular electronic air cleaners and filters * Service less common heating systems such as coal-fired furnaces * Install, maintain, and repair humidifiers and dehumidifers * Handle radiators, convectors, and baseboard heating units

Download or read book Temperature and Humidity Independent Control THIC of Air conditioning System written by Xiaohua Liu and published by Springer Science & Business Media. This book was released on 2014-01-16 with total page 363 pages. Available in PDF, EPUB and Kindle. Book excerpt: Temperature and Humidity Independent Control (THIC) of Air-conditioning System focuses on temperature and humidity independent control (THIC) systems, which represents a new concept and new approach for indoor environmental control. This book presents the main components of the THIC systems, including dehumidification devices, high-temperature cooling devices and indoor terminal devices. Other relevant issues, such as operation and control strategy and case studies, are also included. This book is intended for air-conditioning system designers and engineers as well as researchers working with indoor environments. Xiaohua Liu is an associate professor at the Building Energy Research Center, Tsinghua University, China. Yi Jiang is a member of the Chinese Academy of Engineering, the director of the Building Energy Research Center, Tsinghua University, China and the director of the China-USA Joint Research Center on Clean Energy. Tao Zhang is a Ph.D. candidate at the Building Energy Research Center, Tsinghua University, China.