The energy consumed by heating, ventilating, and air conditioning (HVAC) systems has increased in the past two decades. Thus, improving efficiency of HVAC systems has gained more and more attentions. This concern has posed challenges for modeling and optimizing HVAC systems. The traditional methods, such as analytical and statistical methods, are usually computationally complex and involve assumptions that may not hold in practice since HVAC system is a complex, nonlinear, and dynamic system. Data-mining approach is a novel science aiming at extracting system characteristics, identifying models and recognizing patterns from large-size data set. It has proved its power in modeling complex and nonlinear systems through various effective and successful applications in industrial, business, and medical areas. Classical data-mining techniques, such as neural networks and boosting tree have been largely applied into modeling HVAC systems in literature. Evolutionary computation, including swarm intelligence, have rapidly developed in the past decades and then applied to improving the performance of HVAC systems. This research focuses on modeling, optimizing, and controlling an HVAC system. Data-mining algorithms are first utilized to extract predictive models from experimental data set at Energy Resource Station in Ankeney. Evolutionary algorithms are then employed to solve the optimization models converted from the above data-driven models. In the optimization process, two set points of the HVAC system, supply air duct static pressure set point and supply air temperature set point, are controlled aiming at improving the energy efficiency and maintaining thermal comfort. The methodology presented in this research is applicable to various industrial processes other than HVAC systems.

Providing conditioned and fully controlled room is the final goal for having a comfortable building. But on the other hand making smart controllers to provide the required cooling or heating load depending on occupants' real time feeling is necessary. This study has emphasized on finding a meaningful and steady state parameter in human body that can be interpreted as comfort criterion which can be expressed as the general occupants' sensation through their ambient temperature. There are lots of researches on human physiological behavior in different situations and also different body parts reaction to the same ambient situation. Body parts which have the biggest reliable linear fluctuation to the changes are the best subject for this research. For these tests, wrist and palm have been selected and their temperatures on different people have been measured accurately with thermal camera to follow the temperature trend on various comfort levels. It is found that each person reaches to his own unique temperature on these two spots, when he/ she feels comfortable, or in other word each person's body temperature is a precise nominate for comfort feeling of that individual. So in future by having this unique comfort parameter and applying them to the HVAC system temperature control, controlling the dynamic temperature and correlating the indoor condition depending on the occupants instant thermal comfort level, would be a rational choice to bring convenience while energy has been saved more.

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This diploma thesis is focused on the matter of radiation heating, thermal comfort maintenance and setting optimal operation parameters for heating system equipped with radiation panels. The research section summarizes the effects most important for thermal comfort, methods of its determination, heat exchange distribution between the human body and its environment, and technical possibilities of heating car interiors. The central points of this work are the simulation of car interiors heated with radiation panels and the evaluation of thermal comfort with a virtual mannequin. Thermal state was determined via the equivalent temperature and thermal comfort zones diagram (method by O.H. Nilsson). Forty-two simulated scenarios led us to conclude that thermal comfort is not possible to obtain with panels exuding a maximum temperature of 43 °C and the combination of several heat sources is required. Nevertheless radiation heating considerably contributes to energy savings without the loss of thermal comfort in assessed car.

This work deals with the design and realization of the workplace for the measurement of ventilation parameters of fans, electric machines and other elements. The thesis contains an extensive research part regarding the air-conditioning issues. In the work was designed a channel for measurement, electronics, sensorics, control algorithm and user application. The workplace was completed and tested.

This thesis is about creation of financial plan for the business plan in the area of HVAC. The business plan is about project office, that designs materials used by realisation company. The real market situation was considered during making financial plan and it was made in 2 versions – pesimistic and optimistic. Optimistic version deals with ideal state of company, with a lot of contracts, its purpouse is how to develop our bussiness. Pesimistic version operates with minimal possible income for realistic business.

The aim of the master project is to design a kindergarten in Holubice, Czechia. The building has three parts. First includes classrooms and auxiliary premises (locker rooms, washrooms, etc.), second technical and staff facilities and the third one includes a gym with equipment storage. The first two parts are designed using load-bearing masonry, reinforced concrete floor slab and flat roof. Gym has a load-bearing system combining masonry and structural frame covered by a semi-circular flat roof. The whole building is equipped with HVAC systems. Heating energy is supplied by two condensing gas boilers. Air quality will be maintained by an air conditioning system. Photovoltaic panels are placed on the roof to support electricity. Rainwater will be collected in accumulation tanks and further used for flushing on the toilets and garden irrigation. The project was developed using AutoCAD (drawings) and Revit. The secondary task of the work is an extensive measurement of the CO2 concentration in a room with forced ventilation. The aim is to combine automatic regulation of forced ventilation, depending on the concentration of CO2. The result of such regulation is higher air comfort, service life of individual HVAC members and saving electricity.

The main objective of this thesis is to propose and evaluate two variants of HVAC systems for clean rooms. The proposed system is pressurized. As part of the experimental section in which the data obtained are evaluated - humidity and air temperature.

The aim of this work was to design test bend for vehicle air-conditioning. This test bend should simulate interior of the car and the engine compartment. Electric motor is used to drive compressor in test bend. Air supplied to test bend is modified to extreme conditions and the volume of supplied air is the same as the car drove at 50 km/h. Main frame of test bend is made from aluminium profiles manufactured by Bosch Rexroth, which provides great modularity. Walls are made from insulated panels by ELCOM System, they have very good insulation and are strong so additional equipment can be installed inside. Construction design was made is SolidWorks with 3D models of test bend as output. Air-conditong parts which were used as samples are originally from Skoda Octavia II. For this vehicle were made calculations of heat loads. In conclusion is simple testing example for this test bend and although there are some examples for future measuring.

Practicing engineers need an integrated building, HVAC and control simulation tool for optimum HVAC design and retrofit. Various tools are available to the researchers, but these are not appropriate for the consulting engineer. To provide the engineer with a tool which can be used for typical HVAC projects, new models for building, HVAC and control simulation are introduced and integrated in a user-friendly, quick-to-use tool. The new thermal model for buildings is based on a transfer matrix description of the heat transfer through the building shell. It makes provision for the various heat flow paths that make up the overall heat flow through the building structure. The model has been extensively verified with one hundred and three case studies. These case studies were conducted on a variety of buildings, ranging from a 4m2 bathroom, to a 7755 m2 factory building. Eight of the case studies were conducted independently in the Negev Desert in Israel. The thermal model is also used in a program that was custom-made for the AGREMENT Board (certification board for the thermal performance of new low-cost housing projects). Extensions to the standard tool were introduced to predict the potential for condensation on the various surfaces. Standard user patterns were incorporated in the program so that all the buildings are evaluated on the same basis. In the second part of this study the implementation of integrated simulation is discussed. A solution algorithm, based on the Tarjan depth first-search algorithm, was implemented. This ensures that the minimum number of variables are identified. A quasi-Newton solution algorithm is used to solve the resultant simultaneous equations. Various extensions to the HVAC and control models and simulation originally suggested by Rousseau [1] were implemented. Firstly, the steady-state models were extended by using a simplified time-constant approach to emulate the dynamic response of the equipment. Secondly, a C02 model for the building zone was implemented. Thirdly, the partload performance of particular equipment was implemented. Further extensions to the simulation tool were implemented so that energy management strategies could be simulated. A detailed discussion of the implications of the energy management systems was given and the benefits of using these strategies were clearly illustrated, in this study. Finally, the simulation tool was verified by three case studies. The buildings used for the verification ranged from a five-storeyed office and laboratory building, to a domestic dwelling. The energy consumption and the dynamics of the HVAC systems could be predicted sufficiently accurately to warrant the use of the tool for future building retrofit studies / Thesis (PhD)--University of Pretoria, 1997. / gm2014 / Mechanical and Aeronautical Engineering / unrestricted