Parametric Numerical Simulation of Flow Field in Scaled U-Shaped Ground Test Cell

The high-quality flow field of an aeroengine ground test cell is the basis for accurate and reliable engine testing and obtaining relevant performance data. In this study for a U-shaped ground test cell, first, the similarity dimension analysis between the original model and the $1:10$ scaled model is conducted to verify the accuracy of the numerical simulation of the scaled model. Then, the parametric numerical simulation method is used to study the effects of the augmentor’s diameter and the distance between the engine jail nozzle and the augmentor inlet on the aerodynamic flow field of the ground test cell for the $1:10$ scaled model. The results show that if the diameter of the augmentor tube is too large or too small, the flow rate of the bypass airflow in the augmenter will decrease; thus, the average temperature of the exit section will increase. At the same time, the change of airflow exhaust speed in the blast basket can effectively affect the uniformity of airflow in the silencing tower. With the increase of distances between the engine jail nozzle and the augmentor inlet, the ejection effect of the engine tail jet enhances, but the exhaust velocity in the blast basket decreases; accordingly, the quality of the flow field in the silencer tower significantly deteriorates with the tendency of the vortex centers on both sides of the pipe moving upward. In $\mathit{Case}4$, the airflow velocity at the front chamber inlet of the test workshop is significantly higher than that of the baseline model, $\mathit{Case}0$, and the ejection ratio increases by 19.4%.