The R-7 test stand is an open-loop facility for the investigation of the flow in small centrifugal compressors followed by a volute. The compressor is driven by a 57 kW, variable-speed motor and a 10:1 gear box that allows a maximum shaft speed of 30000 RPM. The impeller is mounted in overhang to facilitate access from all sides to the compressor inlet and outlet. The flow meter device and throttling valve are installed at the compressor inlet to reduce the power required. The facility is equipped with a microcomputer-controlled acquisition system, pressure transducers, scani-valves and microcomputer-controlled probe carriages. This allows on-line data reduction.
The facility is mainly used for detailed three-dimensional measurements of the swirling flow in the volute to assist in the development of a more reliable and accurate performance prediction method.