Application of LDV and PIV techniques for flow measurements in the suction port of a screw compressor

Abstract

Abstract The application of LDV and PIV systems to measure the flow variation in the suction port of a new designed optical screw compressor has been found to be very successful. Time-resolved mean velocity measurements were made over a time window of 1° (Δθ) at a rotor speed of 1000 rpm, a pressure ratio of 1 and a gas temperature of 55°C. The LDV investigation on the suction port has shown a very stable and slow flow with almost no influence of the rotor motions everywhere except close to rotors at Z=-10mm where the rotor motions start to show its influence and formed a more complex flow with a wavy axial flow profile. The PIV results confirmed flow trend measured by LDV and showed no influence of rotors’ movement on the mean flow structure. The PIV results within the vertical plane also showed relatively strong horizontal stream flow vectors upstream of the inlet suction port and became almost vertically downwards at the inlet port. Despite the current success, further improvements have been recommended to give better optical accessibility as close as possible to the rotors entrance.