Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Dynamic Modeling And Control Of A Hybrid Hydronic Heating System
Download Dynamic Modeling And Control Of A Hybrid Hydronic Heating System full books in PDF, epub, and Kindle. Read online Dynamic Modeling And Control Of A Hybrid Hydronic Heating System ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Dynamic Modeling and Control of a Hybrid Hydronic Heating System by : YiTeng MA
Download or read book Dynamic Modeling and Control of a Hybrid Hydronic Heating System written by YiTeng MA and published by . This book was released on 2014 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: A dynamic model of a hybrid hydronic heating system has been developed. Simulations of the control strategies and the model-based energy analysis for the overall system have been presented in this thesis. The hybrid hydronic system is composed of a conventional natural gas fired boiler hot water heating and a ground source heat pump system. The overall system consists of several components such as a boiler, a heat exchanger, a ground loop heat pump, a ground loop heat exchanger, baseboard heaters, and radiant floor hydraulic piping systems. The system model was described by nonlinear differential equations, which were programmed and solved using MATLAB. Two control strategies for improving the overall system performance were explored: (i) a conventional PI control, and (ii) an adaptive gain control. The simulation results subject to set-point changes showed that the performance of the adaptive controller is better than the fixed gain PI controller in disturbance rejection and stability. Energy simulations under three different operating strategies were conducted: (i) a conventional fixed set-point PI control, (ii) an outdoor air temperature reset control, and (iii) an optimal set-point PI control. It was shown that the outdoor temperature reset strategy can save 4.5% and 19.9% energy under cold day and mild day conditions compared to the conventional fixed set-point PI control strategy. In addition, the iv implementation of the optimal PI control strategy result in higher energy savings 6.6% and 22% as compared to the base case under cold and mild day conditions, respectively.
Book Synopsis Dynamic Modeling and Control of Hybrid Ground Source Heat Pump Systems by : Chang Chen
Download or read book Dynamic Modeling and Control of Hybrid Ground Source Heat Pump Systems written by Chang Chen and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ground source heat pump (GSHP) systems are one of the fastest growing applications of renewable energy in the world with annual increases of 10% over the past decade. GSHPs are potentially more efficient than conventional air-to-air heat pumps as they use the relatively constant temperature of the geothermal energy to provide heating or cooling to conditioned rooms at desired temperature and relative humidity. More importantly, GSHP systems can in fact achieve significant energy savings year round, compared to conventional HVAC systems. A hybrid ground source heat pump (HGSHP) system is designed in this study to heat and cool an office building all the year round. Dynamic models of each component of the heat pump system are developed for simulations of heat transfer between each component of the HGSHP system and for control strategy design and analysis. A detailed multiple-load aggregation algorithm (MLAA) is adapted from the literature to precisely account for and calculate the transient heat conduction in vertical ground heat exchangers with different yearly, monthly, and daily pulses of heat. Feedback PI controllers for heat pump units and On/Off controllers for boiler and cooling tower are designed and utilized to match anticipated building loads and to analyze transient response characteristics of such outputs as water flow rate and air flow rate of heat pumps, return water temperature and supply air temperature of heat pumps, water temperatures of ground loops and heat exchangers, water temperature of boiler or cooling tower, and fuel flow rate of boiler. Control strategies for the HGSHP system in both heating and cooling modes of operation are also introduced to study the system responses. With the usage of On/Off controllers and well-tuned PI controllers, as well as optimal control strategies for heating and cooling operations, the HGSHP system is expected to give better operating performance and efficiency. As a result, noticeable energy savings can be achieved in both heating and cooling modes of operation.
Book Synopsis Dynamic Modeling, Intelligent Control and Diagnostics of Hot Water Heating Systems by : Lian Zhong Li
Download or read book Dynamic Modeling, Intelligent Control and Diagnostics of Hot Water Heating Systems written by Lian Zhong Li and published by . This book was released on 2008 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Dynamic Modeling, Intelligent Control and Diagnostics of Hot Water Heating Systems by : Lianzhong Li
Download or read book Dynamic Modeling, Intelligent Control and Diagnostics of Hot Water Heating Systems written by Lianzhong Li and published by . This book was released on 2008 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heating, ventilating and air-conditioning (HVAC) systems have been extensively used to provide desired indoor environment in buildings. It is well acknowledged that 25-35% of the total energy use is consumed by buildings, and space heating systems account for 50-60% of the building energy consumption. Furthermore, roughly half of the energy consumed goes to operation of heating systems. In the past few years the energy use has shown rapid growth. Therefore, it is necessary to design and operate HVAC systems to reduce energy consumption and improve occupant comfort. To improve energy efficiency, HVAC systems should be optimally controlled and operated. This study focuses on developing advanced control strategies and fault tolerant control (FTC) using information from fault detection and diagnosis (FDD) for hot water heating (HWH) systems. To begin with, HWH system dynamic models are developed based on mass, momentum and energy balance principles. Then, embedded intelligent control strategies: fuzzy logic control and fuzzy logic adaptive control are designed for the overall system to achieve better performance and energy efficiency. Moreover, in designing the advanced control strategies, the parameter uncertainty and noise from measurement and process are taken into account. The extended Kalman filter (EKF) technique is utilized to handle system uncertainty and measurement noise, and to improve system control performance. After that, a supervisory control strategy for the HWH system is designed and simulated to achieve optimal operation. Finally, model-based FDD methods were developed by using fuzzy logic to detect and isolate measurement and process faults occurring in HWH systems. The FDD information was employed to design model-based FTC systems for various faults and to extend the operating range under failure situations. The contributions of this study include the development of a large scale dynamic model of a HWH system for a high-rise building; design of fuzzy logic adaptive control strategies to improve energy efficiency of heating systems and design of model-based FTC systems by using FDD information.
Book Synopsis Dynamic Modeling and Model-free Real-time Optimization for Cold Climate Heat Pump Systems by : Wenyi Wang
Download or read book Dynamic Modeling and Model-free Real-time Optimization for Cold Climate Heat Pump Systems written by Wenyi Wang and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Air source heat pump (ASHP) has been a well-received technology to provide space and/or water heating for building and industrial applications, while its efficiency and heating capacity can be severely limited when operated in cold climate. Various modifications have been proposed for cold-climate operation of ASHP over the single-stage refrigeration cycle, such as vapor injection techniques and cascade configuration. However, there has been a lack of effective control strategies for such systems to maintain the optimal energy efficiency for operations across different combinations of ambient and load conditions. Previous work has paid great efforts in model based strategies, anchored on deriving system models with simulation and experimental testing. Such approaches can be prohibitively expensive due to the inherent nonlinear nature of refrigeration systems and unmeasurable equipment degradation. This dissertation investigates on model-free control strategies for real-time efficiency optimization for several configurations of cold-climate ASHP, by use of Extremum Seeking Control (ESC). By utilizing periodic dither inputs for online gradient estimation, ESC bears significant robustness against process variation and external disturbance, which has proved to be more advantageous in handling the challenging applications like heating, ventilation and air conditioning (HVAC) systems. Three types of ASHP configurations are studied in this dissertation: the internal heat exchanger vapor injection, flash-tank vapor injection, and cascade configuration. For both vapor injection ASHP configurations, the intermediate pressure setpoint is optimized by standard ESC and Newton-based ESC based on the feedback of the total power consumption, with the constant heating load considered. For the cascade ASHP, multivariable ESC is designed to handle two operational scenarios: minimizing the total power for fixed heating capacity and maximizing the coefficient of performance (COP) for variable heating capacity. For the power based ESC, the manipulated inputs include the intermediate temperature, high temperature cycle superheat and low temperature cycle superheat; while for the COP based ESC, the high- and low-temperature cycle compressor speeds and evaporator fan mass flow rate are adopted as inputs. The proposed ESC strategies are evaluated with Modelica based dynamic simulation models of the three system configurations. Simulations have been conducted under both fixed and realistic ambient temperature profiles. The simulation results show good steady-state and transient performance of real-time efficiency optimization with the proposed strategies, in terms of tracking unknown and dynamic optimum settings.
Book Synopsis Dynamic Modeling and Optimal Operation of District Heating Systems by : Lianzhong Li
Download or read book Dynamic Modeling and Optimal Operation of District Heating Systems written by Lianzhong Li and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: District Heating Systems (DHS) are widely utilized for space heating in residential and commercial buildings. They offer economic benefits to consumers in terms of lower heating costs. The energy efficiency of DHS can be further improved by optimally controlling the operating parameters of the system. With this as a motivation, dynamic modeling and optimal operation strategies of DHS are explored in this thesis. Two typical District Heating Systems namely Direct District Heating System (DDHS) and Indirect District Heating System (IDHS) are considered. Using typical system configurations the components of the DHS were sized. Dynamic models of the designed DHSS useful for control analysis were developed. Open loop tests subject to constant inputs and loads were conducted to evaluate the time response characteristics of DHS. A methodology for computing optimal operating parameters of DHS is presented. These optimal parameters so computed are used as set points for PID controllers. The DHS by virtue of its long distribution network is subject to large transportation time delays. To compensate such time delays, a PID controller augmented with a Smith Predictor is developed. The designed controller is used to simulate closed loop operation of DHS under variable load conditions. Results show that the optimal set point strategy can save 10%-15% energy compared to conventional control strategies.
Book Synopsis Modeling and Control of Hydronic Building HVAC Systems by : Vikas Chandan
Download or read book Modeling and Control of Hydronic Building HVAC Systems written by Vikas Chandan and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Energy requirements for heating and cooling of residential, commercial and industrial spaces constitute a major fraction of end use energy consumed. Centralized systems such as hydronic networks are becoming increasingly popular to meet those requirements. Energy efficient operation of such systems requires intelligent energy management strategies, which necessitates an understanding of the complex dynamical interactions among its components from a mathematical and physical perspective. In this work, concepts from linear graph theory are applied to model complex hydronic networks. Further, time-scale decomposition techniques have been employed to obtain a more succinct representation of the overall system dynamics. The proposed model is then used to design predictive control strategies which are compared with traditional feedback control schemes using a simulated chilled water system as a case study. The advantages and limitations associated with these methodologies has been demonstrated. The cornerstone of this work is the development of a novel, distributed predictive scheme which provides the best compromise in the multidimensional evaluation framework of 'regulation', `optimality', `reliability' and `computational complexity'.
Book Synopsis Scientific and Technical Aerospace Reports by :
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1981 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Modeling and Control in Air-conditioning Systems by : Ye Yao
Download or read book Modeling and Control in Air-conditioning Systems written by Ye Yao and published by Springer. This book was released on 2016-10-01 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.
Book Synopsis Thermal and Hydraulic Modeling and Control of a District Heating System by : kang Xu
Download or read book Thermal and Hydraulic Modeling and Control of a District Heating System written by kang Xu and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Small-Scale Energy Systems with Gas Turbines and Heat Pumps by : Satoru Okamoto
Download or read book Small-Scale Energy Systems with Gas Turbines and Heat Pumps written by Satoru Okamoto and published by MDPI. This book was released on 2021-03-29 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: A heat pump system can produce an amount of heat energy that is greater than the amount of energy used to run the heat pump system. Thus, a heat pump system is considered to be a machine system that can use energies efficiently, as is the load leveling air-conditioning system utilizing unutilized energies at high levels. Adaptations of gas turbines for industrial, utility, and marine-propulsion applications have long been accepted as means for generating power with high efficiency and ease of maintenance. Cogeneration with gas turbine is frequently defined as the sequential production of useful thermal energy and shaft power from a single energy source. For applications that generate electricity, the power can either be used internally or supplied to the utility grid. This Special Issue intends to provide an overviews of the existing knowledge related with various aspects of “Small-Scale Energy Systems with Gas Turbines and Heat Pumps”, and contributions on, but not limited to the following subjects were encouraged: wake of stator vane to improve sealing effectiveness; gas turbine cycle with external combustion chamber for prosumer and distributed energy systems; computational simulation of gas turbine engine operating with different blends of biodiesel; experimental methodology and facility for the engine performance and emissions evaluation using jet and biodiesel blends; experimental analysis of an air heat pump for heating service; hybrid fuel cell-Brayton cycle for combined heat and power; design analysis of micro gas turbines in closed cycles. Seven papers were published in the Special Issue out of a total of 12 submitted.
Book Synopsis Dynamic Modeling of an HCP System and Its Control by : Jianping Wu
Download or read book Dynamic Modeling of an HCP System and Its Control written by Jianping Wu and published by . This book was released on 1994 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis A Methodology for Modeling of Hydronic Radiant Slab Heating Systems for Predictive Control and Energy Flexibility by : Ali Saberi Derakhtenjani
Download or read book A Methodology for Modeling of Hydronic Radiant Slab Heating Systems for Predictive Control and Energy Flexibility written by Ali Saberi Derakhtenjani and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiant slab heating systems are receiving considerable attention due to the multiple advantages they offer such as improved thermal comfort in buildings and suitability for other related applications in cold climates, particularly snow melting and de-icing of pavements and infrastructure. Hydronic radiant heating can utilize low temperature renewable energy heat sources. The operation of these systems can be optimized by applying predictive control and further the energy costs can be reduced by optimizing their interaction with smart grids by utilizing the flexibility in their demand profiles. However, compared to conventional air heating systems, radiant systems have several added complexities such as the slow transient heat conduction within the slab. Efficient design and operation of radiant slabs require several critical decisions on design and control variables to maintain comfortable thermal conditions in the space and achieve slab surface temperatures within the recommended range depending on the application. This thesis presents a methodology for modelling of hydronic radiant slab heating systems with significant thermal mass (a concrete layer with embedded tubes) for predictive control to utilize the energy flexibility of the building and/or infrastructure in interaction with smart grids and dynamic pricing of electricity. The modelling approaches include low-order grey box models as well as frequency domain techniques. Each approach has its own specific advantages and unique information can be obtained from each one that complement each other when optimizing system operation and designing the control strategies. Using the developed frequency domain model of the zone, key transfer functions are calculated for a case study. By means of transfer functions, the effect of different levels of thermal mass on the zone thermal response and quantification of the energy flexibility in response to grid signals is studied. The model is used to evaluate different design and operation options on a relative basis. It is shown how transfer function analysis provides insight into the building thermal dynamics without the need for simulations. A new transfer function that relates the radiant floor heat source at the bottom of the slab to the zone air temperature is introduced and its derivation is demonstrated. By means of the transfer function, the delay between the heat input of the radiant slab and zone air temperature is determined. Experiments with a full scale test room in an environmental chamber are used to validate the key design parameters obtained from the frequency domain transfer function regarding the operational strategies for energy flexibility of the thermal zone. Frequency domain techniques may also be utilized to establish the appropriate order for low-order RC models for different applications. A low-order thermal network RC model for a case study, validated with experimental measurements, is utilized to study several predictive control strategies in response to changes in the grid price signal, including short term, more reactive changes of the order of 10-15 minutes notice. An index is utilized to quantify the energy flexibility with the focus on the peak demand reduction for specific periods of time when the electricity prices are higher than usual. It is shown that the developed predictive control strategies can aid greatly in minimizing the electricity cost of the building and up to 100% reduction in peak power demand and energy consumption is achieved during the high price periods. Low-order thermal models are also utilized to study radiant slab heating systems of infrastructure that have much higher thermal mass than the radiant slabs in buildings due to structural reasons. Hydronic heating of roads and pavements surfaces to avoid ice formation has several advantages compared to traditional surface salting and other anti-skid methods which have a lot of limitations. However, the traditional method of designing such systems does not consider the thermal mass of the system and its potential for predictive control, energy flexibility and optimized performance. Finally, predictive control strategies are presented and studied to take advantage of the hydronic slab thermal mass and minimize the energy consumption and peak power demand and are validated in a full scale experiment in an environmental chamber.
Book Synopsis Building Performance Simulation for Design and Operation by : Jan Hensen
Download or read book Building Performance Simulation for Design and Operation written by Jan Hensen and published by Taylor & Francis. This book was released on 2011 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book begins with an introduction to the concepts of performance indicators and targets, followed by a discussion on the role of building simulation in performance based building design and operation. This sets the ground for in-depth discussion of performance prediction for energy demand, indoor environmental quality (including thermal, visual, indoor air quality and moisture phenomena), HVAC and renewable system performance, urban level modelling, building operational optimization and automation. This book provides a unique and comprehensive overview of building performance simulation for the complete building life-cycle from conception to demolition.
Book Synopsis Fundamentals of Building Energy Dynamics by : Bruce D. Hunn
Download or read book Fundamentals of Building Energy Dynamics written by Bruce D. Hunn and published by MIT Press. This book was released on 1996 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of Building Energy Dynamics assesses how and why buildings use energy, and how energy use and peak demand can be reduced. It provides a basis for integrating energy efficiency and solar approaches in ways that will allow building owners and designers to balance the need to minimize initial costs, operating costs, and life-cycle costs with need to maintain reliable building operations and enhance environmental quality both inside and outside the building. Chapters trace the development of building energy systems and analyze the demand side of solar applications as a means for determining what portion of a building's energy requirements can potentially be met by solar energy. Following the introduction, the book provides an overview of energy usepatterns in the aggregate U.S. building population. Chapter 3 surveys work onthe energy flows in an individual building and shows how these flows interact to influence overall energy use. Chapter 4 presents the analytical methods, techniques, and tools developed to calculate and analyze energy use in buildings, while chapter 5 provides an extensive survey of the energy conservation and management strategies developed in the post-energy crisis period. The approach taken is a commonsensical one, starting with the proposition that the purpose of buildings is to house human activities, and that conservation measures that negatively affect such activities are based on false economies. The goal is to determine rational strategies for the design of new buildings, and the retrofit of existing buildings to bring them up to modern standards of energy use. The energy flows examined are both large scale (heating systems) and small scale (choices among appliances). Solar Heat Technologies: Fundamentals and Applications, Volume 4
Download or read book Energy Research Abstracts written by and published by . This book was released on 1987 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Issues in Energy Research and Application: 2011 Edition by :
Download or read book Issues in Energy Research and Application: 2011 Edition written by and published by ScholarlyEditions. This book was released on 2012-01-09 with total page 482 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Energy Research and Application / 2011 Edition is a ScholarlyEditions™ eBook that delivers timely, authoritative, and comprehensive information about Energy Research and Application. The editors have built Issues in Energy Research and Application: 2011 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Energy Research and Application in this eBook to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Energy Research and Application: 2011 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
