A study of leakage flows in oil-free rotary positive displacement machines (PDMs) is necessary to get a real insight into the attributes of leakage flows. It is challenging to obtain velocity field and temperature field of the leakage flow in the running conditions of the machine. Therefore, this study focuses on developing an experimental setup that can measure the velocity field and temperature field with the controlled operating parameters of the machine. This study is a part of SECRET (Smart Efficient Compression, Reliability and Energy Targets) project which is supported by an award from The Royal Academy of Engineering to City, University of London's Centre for Compressor Technology and Howden Compressors.
National Instrument-based data acquisition system is designed to measure and control machine operating parameters such as pressure, temperature, flow, power, and speed by implementing appropriate sensors. The particle image velocimetry (PIV) is identified for velocity field measurement, and setup is designed using optical components. For temperature field measurement, the Planar laser-induced fluorescence (PLIF) is selected based on a feasibility study carried out of PLIF for the current application, and the setup is designed for in-house experiments. High-speed infrared thermography is chosen to measure the surface temperature of a rotary element in operating condition. A combination of PIV, PLIF, and Infrared thermography can produce velocity field, temperature field, and surface temperature history of a lobe. Experimental results will help to generate data of aerothermal behaviour in clearance flows of PDMs, and it will provide a benchmark case for CFD validation.