Numerical and Experimental Investigation on Heat Exchange Performance for Heat Dissipation Module for Construction Vehicles 2017-01-0624

In this work, a XD132 Road Roller from XCMG in China was employed as a research basis to study the heat exchange performance of the heat dissipation module under varied working conditions. The module in the XD132 consists of a cooling fan and three radiators. At first, the numerical investigation on the elementary units of radiators was performed to obtain Colburn j factor and Fanning friction f factor, which were used for the ε-NTU method to predict the radiator performance. The fan was numerically tested in a wind test tunnel to acquire the performance curve. The performance data from both investigations were transformed into the boundary conditions of the numerical vehicle model in a virtual tunnel. A field experiment was carried out to validate the simulation accuracy, and an entrance coefficient was proposed to discuss the performance regularity under four working conditions. The results show that the simulation results of radiators and fans could be applied to the vehicle simulation, and the turbulent airflow at the exit of the fan partly lowers performance. Besides that, the elevated-temperature air flowing out of the fan is reheated by the muffler and results in a working instability. The maximum error between simulation results and experimental data is less than 4%. The comparison between four working conditions also confirms that the heat exchange performance decreases as the vehicle moves forward at an increasing velocity and increases as the vehicle moves backward. The conclusions are of great significance in efficiency improvements on the vehicle design.