A Measurement System for the Performance Evaluation of Roots Blowers

The rotary positive-displacement Roots mechanisms are popular used in industries and instruments as vacuum pump, blower, or supercharger, etc. As a mechanical blower design, its performances are affected by a variety of factors such as geometries, rotational speed, clearances, and operating processes. In this study, a Roots supercharger is investigated by a self-developed testing system which is designed following the SAE J1723 standard. Both of inlet and outlet temperatures and pressures are recorded as methods mentioned in standard. A flowmeter is installed in inlet system to detect the flow rates and a rotary torque transducer is used to measure the torque transmitted from motor to blower and the rotational angular speed. Automatic data acquisition system is built to gather all relevant data into notebook for further data analysis. Pressure ratio, isentropic efficiency and volumetric efficiency are investigated for the specific Roots blower under different testing conditions. This tool will be beneficial to testing of different blower productions in industries.