Numerical and experimental investigations of heat transfer in a cross-flow heat recovery system

Nowadays, ventilation is obligatory in buildings where human beings spend a large part of their life. To maintain indoor air quality, dirty indoor air is exhausted and fresh air is taken from outdoors. In modern systems, dirty indoor air with high energy is not exhausted directly. By the help of air to air heat exchangers, fresh air from outdoors is pre-heated or pre cooled by the help of exhausted air thus decreases the energy used to condition indoor air. In HVAC Systems, between 35 percent and 90 percent ratio of waste heat energy recovery is possible. Plate type, rotary, heat pipe and coil heat exchangers are widely used as heat recovery exchangers. In this research, the efficiency of heat recovery exchanger was researched numerically. The dimensions of the exchanger which was designed by a manufacturer company are 600x600x600mm. This heat exchanger was investigated for the real boundary conditions and turbulent flow with the help of the program Ansys Workbench. According to fin characteristics and flow patterns, created models were analyzed. Heat exchanger which developed by manufacturer company was experimented on testing laboratory which was founded by the company. The results of the tests and theoretical research are shown compatibility of numerical analysis. As the results are compatible with each other, the finite element method for heat recovery efficiency of the exchanger was found to be a reliable method.