An experimental technique to simulate and measure leakages in twin-screw compressor

Abstract

The phenomenon of leakages through various clearances in the twin-screw compressor and its accurate prediction affect its design and performance. The blowhole leakage within the twin-screw compressor is estimated by previous researchers using the convergent nozzle equation, which has certain idealized assumptions and hence has a scope of improvement considering the actual phenomena taking place within the screw compressor. The mathematical model presented in this study takes into account, the shape of a gap and its geometric dimensions, the parameters before and after the gap, the gas friction and the local resistance at entry and exit. An iterative model is used to calculate the leakage rate through the blowhole cross-sections at different pressure differences. The analytical results for the leakage using the mathematical models are verified experimentally by simulating the leakages through the circular cross section convergent nozzles of different sizes at different pressure differences. The experimental study along with analytical deduction suggests suitable multiplier to estimate the blowhole leakages within ±7.2%. This methodology may be extended to estimate the other types of leakages occurring dynamically within the screw compressor and fluid flow systems.