APPARATUS FOR EVALUATING EFFICIENCY OF HYDRAULIC FLUID DISPLACEMENT DEVICES

摘要

1519276 Testing pumps W HOFFLINGER 18 March 1977 [30 Nov 1976 (2)] 11632/77 Heading F1A Apparatus for evaluating the efficiency of an hydraulic fluid displacement device 1, e.g. a positive-displacement pump or motor, comprises an hydraulic circuit connected between the high and low-pressure sides of the device, means in the circuit, e.g. a throttle 8 for effecting a substantially isenthalpic change of state of the fluid, another means, e.g. an expansion/compression arrangement 7, for effecting a substantially isentropic change of state of the fluid on one side of the isenthalpic change means, and first, second and third sensors A, B, C for measuring the temperature at the lowpressure side, at the isentropic change means and on the other side of the isenthalpic change means, respectively. An electronic circuit is described for processing the sensor outputs and displaying the efficiency reading.