A ground source heat pump (GSHP) system utilizes a borehole heat exchanger to extract energy from the ground during the heating season and to deposit energy during the cooling season. This requires the drilling of an extended borehole, typically ranging from 100 to 200 meters in length, with a diameter of approximately 6 to 8 inches. Inside the borehole, a U-shaped tube is placed and surrounded by a grout that aids heat transfer between the tube and the surrounding soil. A heat transfer fluid, often a mixture of water and glycol, circulates through the tube to exchange heat with the ground. During the winter, the system draws energy from the ground for household space heating, while in the summer, when air conditioning is used, it expels energy from the house into the ground. In regions with heating-dominated climates, such as Canada, more energy is withdrawn from the ground during the winter than can be naturally restored during the summer. Consequently, the soil progressively cools over time, leading to reduced heat pump coefficient of performance and a decline in the overall system efficiency. This study explores a solution to this issue by integrating solar domestic hot water systems which employ solar thermal collectors to heat water for domestic purposes. These systems are relatively straightforward, consisting of solar thermal collectors, piping, pumps, a hot water tank, and controllers. The collector area is designed to deliver high solar fractions during the summer, but it typically exhibits lower efficiency in the winter. In Toronto, annual solar fraction, defined as the proportion of energy supplied by the solar thermal system to the total energy required by the load, typically range between 50-70%. This research aims to leverage solar thermal collectors for recharging the ground during the summer months. This approach enables the installation of larger collector areas, improving system performance in the winter, while simultaneously depositing excess energy into the ground during the summer. Notably, this study focuses on a single household located in Toronto, Canada, where the recommended solar thermal collector area is 10 square meters, and the borehole heat exchanger length is 150 meters. Also, it is assumed that four people are living in this house and required energy for heating and cooling of the house are 28000 and 7000 kWh per year, respectively. This approach offers a promising solution to balance seasonal heat transfer to the ground, mitigating the long-term decline in GSHP performance. The study demonstrates that by coupling the solar thermal system with the GSHP, the targeted outcomes are achievable. / Thesis / Master of Applied Science (MASc)

An experimental investigation has been carried out to study the heat transfer in a two-phase two-component mixture flowing upward inside a 1" double pipe heat exchanger. The heat transfer coefficient was measured using either air to lift the liquid (air-lift system) or a mechanical pump. The heat transfer coefficient results have been extensively studied and compared with other workers' results. An attempt was made to correlate the present heat transfer data in dimensionless correlations. Possible factors affecting the two-phase heat transfer coefficient have been studied with special attention being given to the fluid properties, particularly the liquid viscosity. Experiments were also carried out to investigate the effect of solid particles added to a liquid flow on the measured heat transfer coefficient. The present investigation was carried out using air as the gas-phase ranging from 2x 10-5 up to 80 x 10-5 m3/s. Liquids used were water and glycerol solutions with viscosity ranging from 0.75 up to 5.0 C. P. and flowrates between 4x 10-5 and 25 x 10-5 m3/s. Void fraction and pressure drop were also measured during the heat transfer process. Flow pattern in gas-liquid mixture was investigated in a perspex tube of identical dimensions to the heat exchanger tube.

The diploma thesis aims to establish thermo-hydraulic properties of a flexible tube described by its Darcy friction factor and film heat transfer coefficient respectively. A flexible tube (corrugated stainless steel tube) is an easily shapeable stainless steel component used to build various piping connections, in a place of more common copper or plastic made tubes. It can also be used to build heat exchangers thanks to its signature properties. The investigated product is the one developed and manufactured by the Czech company Flexira s.r.o. and sold under the brand name xConnect System. Its thermo-hydraulic properties are established by an experiment, which is based on real utilizations by Laboratory of Energy Intensive Processes in NETME (New Technologies for Mechanical Engineering) Centre at Brno University of Technology. The investigated case is a coil-shaped element serving a purpose of a water-to-water heat exchanger. The text contains a literature survey of the chosen flexible tube and a description of a draft and development of the specific experimental test based off the established theory. The obtained results are then analysed, for the purpose of establishing a functional dependence, which can then be used to calculate a film heat transfer coefficient.

This diploma thesis deals with the design and optimization of the control valve for EHRS exchanger. The first part of the thesis contains a research describing the historical development of internal combustion engines, their impact on the environment and especially the possible ways of waste heat recovery. The second part focuses on the design of the control valve and experimental measurement to verify its functionality. The final part contains an analysis of pressure losses of the designed valve to improve its construction disadvantages.

This diploma thesis is focused on problems of heat exchangers. There are two main objectives. The first objective is based on long-term measuring of enthalpy heat exchanger, processing of measured data and comparison of result with manufacturer's results. The second objective is design of variant solutions for two types of heat exchanger of air conditioning unit of selected shop. For variant without moisture transportation was selected cross flow exchangers. Thanks to knowledge from long-term measurement, was selected enthalpy heat exchanger for variant with moisture transportation. Chosen variants were compared with emphasis on heat and moisture exchange efficiency with requirements on Ecodesign.

This diploma thesis deals with various ways of energetically advantageous utilization of waste heat produced by industrial technologies. The focus of the diploma thesis is both to provide an overview of different ways and places of origin of waste heat in industrial technologies and of its possible reutilization, to suggest a concrete air heating system using waste heat and to propose a long-distance hot water pipe which supplies hot water pipe system with energy. First, technologies producing waste heat and some ways of regressing of heat in such technologies are theoretically described. Second, the equipment for transferring of heat and for adjustment of thermal energy parameters is described. A special focus is put on water supplies of the Nuclear Power Plant Dukovany and some selected parts of its secondary circuit, which is waste heat collected from. The analysis is supplemented by a calculation of theoretical quantity of waste heat. The aim of the calculation is to determine whether waste heat can be a source of energy for heating. Then, a current system of heating of three selected buildings in the area of the Nuclear Power Plant Dukovany is briefly described. Based on the gained knowledge, a project of air heating with two heat pumps type water – water, a heat receiver preparing warm service water and three recuperative units for preheating of fresh heating air is designed. The selection of main parts of the air heating is amended by a calculation of purchase costs and electric energy consumption. After that, the focus is placed on choice of type of hot water pipe – its trace is stated and an indicative estimation and a thermal-conditions calculation in the hot water pipe are made. The preliminary calculation serves as a source of information for a final project of air heating and calculation of changes of temperatures longwise the hot water pipe. The project contains also a calculation of pressure losses and an analysis of economical questions concerning hot water pipes. In conclusion, the results of project of air heating and hot water pipes are summarized.

This master’s thesis is devoted to problematic of selection of suitable flow directions in double pipe heat exchanger. First chapter is oriented to the construction of tube heat exchangers. It is also discussed impact of construction solution to the flow character and changing of his process parameters. The difference between parallel and countercurrent flow is also occurred in this parts. The next chapter is focused to the basics of heat-hydraulic calculations of heat exchanger. This also means explanation of ways of heat transfer and heat exchanger function. There are told about specific access to the solving problem of fluid laminar flow. The third chapter is detailed focused to the calculating of heat exchanger. At first is discussed factors, which have impact to the flow character. Next are detailed descriptions of design and controlling calculations, including more alternative ways to solve it. Next chapter exploit those results for deciding, which flow arrangement will be better for given case. Last chapter contain realization and reformulating of process heat exchanger calculating to the program code in Maple. There is also description of used algorithms and operating with them, so any user could be able to work with it. In this master’s thesis are used many examples from attached programs on different parts.