Thermal Performance of HAVC System Using Heat Pipe Heat Exchanger

To reduce the energy consumption by (HVAC) systems without changing the required temperature level in the air-conditioner space, (HPHX) used has been and tested. The heat pipe heat exchanger (HPHX), were consists of a group of 40 heat pipes arranged as 4 rows, each row contains 10 copper tubes. The length of the pipe was 73 cm, the inner diameter ID= 1 cm, and the outer diameter OD= 1.23 cm. With distilled water, the heat pipe was filled with at about 50% of the volume of the evaporator which represents the filling ratio. Several experiments were studied to assess the effect of air velocity on the difference in the incoming and outgoing air temperature on the evaporator and condenser part of heat pipes for different quantities of the heat flux. Moreover the effectiveness of the heat pipe heat exchanger at different velocity (1m/s, and 2m/s), and the ratio of the heat recovery was found in the evaporator were also determined. The study revealed that the temperature change of the evaporator and condenser will increase with increasing heat flux and air velocity which passing on (HPHX). The result illustrate that the heat flux increasing and decreasing the air velocity lead to increase the effectiveness of the heat pipe. The highest level of effectiveness was 0.646 at heat flux 1400 watt with velocity 1m/s. Highest value of heat recovery 923.4 watt at velocity 2m/s with heat flux 1400 watt and the optimum effectiveness value was obtained at the evaporator 33.6°C temperature inlet, the evaporator 31.7°C temperature outlet and the condenser 29.2°C temperature inlet.