Development of the methodology for testing experimental oil pumps of a vertical spiral compressor

Abstract

In the design vertical scroll compressors, engineers often need to calculate an oil pump that influences the compressor’s features, performance and reliability. The article presents the first research stage for developing the method for calculating such pumps: development of an experimental method for investigating the oil pump; comparison of the physical experiment using the developed method with known patterns; testing the influence of the angle of the inlet nozzle on the pump’s performance.
The authors analysed the publicly available materials and selected the structural elements that affect the pump or which effect needs to be checked. Moreover, the authors developed an experimental test bench and a method of conducting the experiment, which allowed considering the design features of the pump: the diameter of the channel; the diameter of the nozzle opening; the shape of the nozzle; the frequency of rotation of the shaft.
The error analysis reveals that the experiment's relative error is less than 3 %. Based on experimental data, the following dependencies are formulated according to the developed method: there is an inverse dependence of the pump pressure from the ratio of the hole radius at the pump outlet to the radius of the pump duct; there is a quadratic dependence of the pump pressure on the speed. These dependencies are consistent with the known data, which leads to a conclusion about the adequacy of the developed methodology and its applicability in further studies. Moreover, the authors also verify that the shape of the nozzle does not affect the pump’s performance. The results of the experiment presented in the article can be applied for verifying mathematical models of scroll compressors.