Affiliation:
1. Faculty of Technology, Technical University in Zvolen, Studentska 26, 960 01 Zvolen, Slovakia
Abstract
The paper deals with an experimental investigation of a new approach for cooling the external heat exchange surfaces of a cooler using an air pressure nozzle system. The G12+ coolant (50:50 ethylene glycol/water concentrate) is heated to an operating temperature of 80 °C and cooled by a cooler. Three ways of forced cooling of the external heat exchange surfaces of the cooler are experimentally compared—fan, nozzles, and a combination of nozzles and fan. The spacing between the nozzles and the cooler is variable from 60 to 170 mm in inline and staggered nozzle arrangements. Coolant temperatures in the cooler inlet and outlet pipes are recorded by thermistors. The air pressure nozzle system achieved an improvement in the cooling process compared to a conventional fan. At a spacing of 160 mm, the heat exchange surface is completely covered by the air flow, which leads to a reduction in cooling time and an increase in the temperature difference. The maximum temperature difference of 28.84 °C and 16.90 °C for staggered arrangement of nozzles at a spacing of 160 mm are achieved for the combination of nozzles with fan and nozzles, respectively. When comparing 60 mm and 160 mm spacing, there was an increase in thermal performance of 70.3%, 55.99%, 6.20%, and 1.83% for inline nozzles, staggered nozzles, fan with inline nozzles, and fan with staggered nozzles, respectively. The air nozzle system fully replaces the fan in the cooling process and achieves improved heat dissipation, making the cooling process significantly shorter and more efficient. In addition, the air nozzle system can also be used as an additional equipment for intensification of heat dissipation in combination with the fan.