Research on the Impact of Heating Conditions for Passive Air-Cooling System Wind Loading Performance Test

The wind loading test serves as a critical validation experiment for the Passive Air-Cooling System (PAS) ACP100. However, it remains unclear how the highly scaled-down experimental setup can accurately account for the influence of the steel shell wall heating conditions on the airflow dynamics within the PAS flow channel. This study employs both numerical simulations and experimental investigations to compare and analyze variations in pressure and temperature within the PAS flow channel under the different heating temperatures of a steel shell wall, considering scenarios with and without environmental wind field effects. The objective is to assess the influence and necessity of heating conditions. In this study, ANSYS Fluent 18.2 was utilized to conduct numerical simulations of the 1:126 scale model of ACP100. Subsequently, the 1:126-scale ACP100 test model was placed on a wind tunnel platform to investigate various experimental conditions. Key parameters, including pressure, temperature, and wind velocity, were meticulously measured at critical locations to obtain detailed insights into the model’s performance under different scenarios. The results indicate that the numerical calculations are consistent with the findings from experimental research. When the environmental wind velocity is 0 m/s, the pressure deviation (∆Pmax) at each measurement position within the PAS flow channel, under varying heating wall temperatures of 55.8 °C, 93.5 °C and 126.8 °C, remains below 1.8 Pa. Furthermore, the inlet and outlet pressure difference (∆Pio) is less than 3.9 Pa, which is insufficient to establish natural circulation. Additionally, it was observed that the air temperature increases continuously from the PAS inlet to the top outlet; notably, the air temperature at the top outlet approaches that of the heating wall temperature, nearly reaching equilibrium. When examining the coupling effect of the environmental wind field, it is observed that the pressure difference (∆Pio) between the inlet and top outlet of the PAS flow channel increases significantly. However, the pressure deviation at each measurement position within the PAS flow channel remains within acceptable limits, satisfying ∆Pmax < 3 Pa. Furthermore, the temperature deviation (∆Tmax ≤ 2.8 °C) at each measuring position in the PAS channel indicates that the influence of the environmental wind field on both pressure and temperature distribution is relatively minor and can be safely neglected. In summary, it can be concluded that when utilizing the ACP100 scaled-down model for research on a PAS wind loading performance test, there is no necessity to establish heating conditions as their effects can be disregarded.