Author: Simon Winata Publisher: ISBN: Category : Languages : en Pages : 364
Book Description
This study investigated building energy consumption mainly on the HVAC system supply fan energy consumption and building reheat energy. HVAC system for a building often operates using either Constant Air Vo1ume (CAV) system or Variable Air Volume (VAV) system. The CAV system supplies a constant amount of air into each zone by varying the supply air temperature. On the other hand the VAV system operates by responding to each zone's load requirements by varying the air flow rate through a combination of pressure controls and VAV damper position. A VAV system can be operated by utilizing a variable speed drive fan to achieve optimum saving. There are several techniques that can be applied to control the supply fan speed; two of which were being compared in the study. One technique that is commonly used is constant static pressure control. The supply fan is controlled to maintain a constant static pressure at an arbitrary point in the duct system. Another technique is called Terminal Responsive Static Pressure (TRSP) control which gradually decrease or increase the duct static pressure set-point according to the system's needs. As mentioned above the second part of the study focused on the system reheat energy. There are many systems that can be used to meet the heating load of a building. These include perimeter base board heater using either electric or hydronic system, terminal reheat (electric or hydronic), dual duct system, and others. This research investigated the advantages and disadvantages of hydronic and electric terminal reheat by doing energy simulation with DOE-2 and performing economic analysis on both systems.
Author: Charles Nehme Publisher: Charles Nehme ISBN: Category : Technology & Engineering Languages : en Pages : 88
Book Description
Preface: Navigating the World of Variable Air Volume (VAV) Systems Welcome to the fascinating world of Variable Air Volume (VAV) systems, where the art and science of HVAC (Heating, Ventilation, and Air Conditioning) converge to create efficient, comfortable, and environmentally friendly indoor environments. If you've ever wondered how modern buildings manage to maintain just the right temperature, humidity, and air quality while minimizing energy consumption, you're about to embark on a journey of discovery. In today's rapidly changing world, energy efficiency and sustainability have become paramount concerns. Whether you're an HVAC professional seeking to deepen your knowledge, a building owner aiming to optimize your facility's performance, or simply a curious individual eager to understand the systems behind your daily comfort, this book is your gateway to mastering VAV systems. **Unveiling the Complexity Behind the Comfort** Variable Air Volume (VAV) systems are the hidden heroes of climate control. They are the intelligent, adaptable systems responsible for regulating the air we breathe in offices, hospitals, shopping malls, and countless other spaces. Yet, these systems often operate unnoticed, silently adjusting airflow and temperature to create a pleasant, productive environment. This book takes you behind the scenes, unraveling the complexity of VAV systems and revealing the inner workings of the technology that has transformed the way we experience indoor comfort. From the fundamentals of HVAC to the intricate design and control strategies of VAV systems, you'll gain a deep understanding of how these systems contribute to energy savings, enhanced comfort, and a greener planet. **Your Guide to VAV Mastery** Our journey begins with the basics, ensuring that everyone, regardless of their prior knowledge, can grasp the core concepts. We'll explore the components of VAV systems, discuss their benefits, and delve into the design and installation processes. You'll learn how to troubleshoot common issues, conduct maintenance, and even retrofit existing systems for greater efficiency. But this book doesn't stop at the basics. We'll explore advanced topics such as energy-efficient practices, sustainable design principles, and the integration of VAV systems into smart buildings. You'll gain insights into real-world applications across various sectors, from commercial buildings to healthcare facilities, all while keeping an eye on future trends and innovations that promise to shape the HVAC landscape. **Empowering You with Knowledge** Our aim is to empower you with knowledge that will not only help you excel in your professional pursuits but also make informed decisions about the indoor environments you inhabit. By the time you reach the last page, you'll be equipped to optimize VAV systems, reduce energy consumption, and contribute to a more sustainable future. As you embark on this educational journey, keep in mind that VAV systems are not just about engineering and technology; they're about enhancing the quality of life for people in buildings all around the world. I hope you find this book informative, engaging, and inspiring, and I encourage you to apply the knowledge you gain here to make a positive impact on the spaces we live and work in. Let's venture forth into the world of Variable Air Volume (VAV) systems, where innovation meets comfort, and where we discover the limitless potential of efficient HVAC solutions. Best regards, Charles Nehme HVAC Q & A What is HVAC? HVAC stands for heating, ventilation, and air conditioning. It is a system of technology that controls the temperature, humidity, and ventilation of indoor and restricted spaces. How does HVAC work? HVAC systems typically use a combination of heating and cooling elements, fans, and ductwork to control the indoor environment. The specific components and operation of an HVAC system will vary depending on the type of system and the specific needs of the building. What are the different types of HVAC systems? There are many different types of HVAC systems, but some of the most common include: * Central heating and cooling systems * Split systems * Ductless mini-split systems * Heat pumps * Furnaces * Air conditioners How do I choose the right HVAC system for my home? When choosing an HVAC system for your home, there are a number of factors to consider, such as the size of your home, the climate you live in, your budget, and your energy efficiency goals. It is important to consult with a qualified HVAC professional to get the best advice for your specific needs. What is the best way to maintain my HVAC system? The best way to maintain your HVAC system is to have it inspected and serviced by a qualified professional on a regular basis. This will help to ensure that your system is operating efficiently and safely. You should also change your air filter regularly, according to the manufacturer's recommendations. Short answer: HVAC stands for heating, ventilation, and air conditioning. It is a system of technology that controls the temperature, humidity, and ventilation of indoor and restricted spaces. There are many different types of HVAC systems, and the best way to choose the right one for your home is to consult with a qualified HVAC professional. To maintain your HVAC system, have it inspected and serviced by a qualified professional on a regular basis and change your air filter regularly.
Author: Ye Yao Publisher: Springer ISBN: 3662533138 Category : Technology & Engineering Languages : en Pages : 496
Book Description
This book investigates the latest modeling and control technologies in the context of air-conditioning systems. Firstly, it introduces the state-space method for developing dynamic models of all components in a central air-conditioning system. The models are primarily nonlinear and based on the fundamental principle of energy and mass conservation, and are transformed into state-space form through linearization. The book goes on to describe and discuss the state-space models with the help of graph theory and the structure-matrix theory. Subsequently, virtual sensor calibration and virtual sensing methods (which are very useful for real system control) are illustrated together with a case study. Model-based predictive control and state-space feedback control are applied to air-conditioning systems to yield better local control, while the air-side synergic control scheme and a global optimization strategy based on the decomposition-coordination method are developed so as to achieve energy conservation in the central air-conditioning system. Lastly, control strategies for VAV systems including total air volume control and trim & response static pressure control are investigated in practice.
Author: Guo Rong Zheng Publisher: National Library of Canada = Bibliothèque nationale du Canada ISBN: 9780612259270 Category : Air conditioning Languages : en Pages : 206
Book Description
Energy conservation and indoor environment concerns have motivated extensive research on various aspects of control of Heating, Ventilating and Air-Conditioning (HVAC) and building systems. The study on optimal operation as well as modeling of HVAC and building systems is one of the fastest growing fields that contribute to saving energy and improving indoor environment. This thesis is devoted to the development of a comprehensive modeling and optimization methodology for global multiple-stage optimal operation of HVAC and building systems. Two different dynamic models of a multizone variable air volume (VAV) system have been developed using (i) bottom-up and (ii) top-down approaches. The models take account of the dynamic interactions between building shell, VAV system components and control systems. The models describe the dynamics of fan, air distribution system, zone(s), cooling coil and primary plant (chiller) as one multivariable nonlinear system in a way that is useful for control analysis. Using the bottom-up approach a large-scale VAV system model has been developed. This model considers the interactions between flow field and thermal field via distributed capacity and variable air density considerations. An alternate model which is computationally more efficient was developed using the top-down approach. Model reduction techniques were applied to develop a reduced-order state space model of the VAV system. Results show that predictions from the reduced order model are within 5% of those from the large scale model. Optimal control schemes are developed for the efficient operation of VAV systems. In the control scheme proposed it is necessary to compute optimal setpoint profiles for local controllers. The optimal control profiles so computed can be used as tracking signals for local controllers for moving the system states from one setpoint to another. In order to determine optimal setpoint profiles an optimization methodology for formulating and solving the multiple stage optimal operation problems has been developed. The methodology is based on the maximum principle of Pontryagin and perturbation method in order to deal with the multiple time-scale of the HVAC processes and building operating schedules. A solution methodology and the corresponding computer models have been developed for solving the multiple stage optimal operation problems. The applications of the VAV model and the multistage optimization methodology have been demonstrated by considering several practical examples. The examples include (i) a comparison of optimal strategies for constant and variable air volume systems with and without time-of-day price structure for electrical energy, (ii) a two-zone VAV heating system and (iii) a five-zone VAV cooling system. Results showing the 24-hour optimal setpoint profiles, energy cost savings and the output responses such as zone temperatures and humidity ratios are given for different building operation schedules. These applications show that the developed models and optimization methodology can be used to determine energy efficient operating strategies for VAV systems without violating the thermal comfort in buildings.
Author: Napoleon Enteria Publisher: Springer Nature ISBN: 9811968330 Category : Science Languages : en Pages : 251
Book Description
This book compiles the latest research, development, and application of VRF systems with contributions from various experts who pioneered and contributed to the development of the VRF system. This book presents the fundamental issues related to the real application and behaviour of the VRF system based on the long-term monitoring of the installed system. With our experience of pandemic which COVID-19 is an airborne, the spread of the virus is very fast. With this, the heating, ventilating and air-conditioning (HVAC) system is a major player in the maintenance and control of indoor environment to minimize the spread of the virus. As the variable refrigerant flow (VRF) system is a versatile HVAC system in which it can operate at different conditions, the application of the VRF system is very important to control the indoor environmental conditions. Thus, the publication of this book is important with the present situation and the future possible situation which the control of indoor spaces is very important. With this, this book will serve as a reference for building designer, contractors, building regulators and students.
Author: Charles Nehme Publisher: Charles Nehme ISBN: Category : Technology & Engineering Languages : en Pages : 39
Book Description
Air conditioning systems play a crucial role in providing comfortable indoor environments, whether it's in residential, commercial, or industrial settings. Understanding the principles of psychrometrics is essential for designing, operating, and optimizing these HVAC (Heating, Ventilation, and Air Conditioning) systems effectively. Psychrometrics is the study of the thermodynamic properties of air and its moisture content. It involves the measurement and analysis of parameters such as temperature, humidity, pressure, and enthalpy to determine the state of air and its ability to hold moisture. These parameters are crucial for designing air conditioning systems that can maintain optimal indoor conditions for human comfort, equipment operation, and various industrial processes. This book aims to provide a comprehensive understanding of psychrometrics and its practical applications in HVAC systems. It explores the fundamental concepts and equations related to air properties, psychrometric charts, and the psychrometric processes involved in air conditioning. Moreover, it delves into the various components and systems that make up an air conditioning system, such as air handlers, cooling coils, refrigeration cycles, and ventilation systems. Optimizing air conditioning systems is a key focus of this book. By leveraging the principles of psychrometrics, engineers and technicians can enhance the efficiency and performance of HVAC systems, resulting in energy savings, improved indoor air quality, and increased occupant comfort. The book covers topics such as load calculations, equipment selection, airflow distribution, humidity control strategies, and system optimization techniques. Throughout the book, real-world examples, case studies, and practical tips are provided to illustrate the application of psychrometrics in different scenarios. Whether you are a HVAC professional, engineer, technician, or someone interested in understanding the inner workings of air conditioning systems, this book serves as a valuable resource to enhance your knowledge and skills. It is worth noting that while this book provides a comprehensive overview of psychrometrics and air conditioning systems, it does not delve into the intricacies of HVAC design and installation. For detailed design guidelines and standards, it is recommended to refer to relevant industry codes, manuals, and regulations. With a solid understanding of psychrometrics and its role in air conditioning systems, readers will be equipped with the knowledge necessary to design, optimize, and maintain efficient HVAC systems, creating comfortable and healthy indoor environments for all. Let us embark on this journey into the fascinating world of HVAC psychrometrics and unlock the secrets of optimizing air conditioning systems.
Author: Simon Winata
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Author: Jeremy Silva
Author: Zhentao Wei
Author: Charles Nehme
Author: Ye Yao![Dynamic Modeling and Global Optimal Operation of Multizone Variable Air Volume HVAC Systems [microform] PDF](https://books.google.com/books/content/images/frontcover/IywZygAACAAJ?fife=w80-h100)
Author: Guo Rong Zheng
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Author: Napoleon Enteria
Author: Charles Nehme