Speed of sound measurements of HFO-1234ze(E) in the liquid phase.

The present study deals with an experiment to investigate speeds of sound of refrigerant HFO-1234ze(E) at near saturated and compressed liquid conditions. The measurement system is mainly composed of an ultrasonic sensor and a standard resistance temperature detector and two pressure transducers. The measurements were conducted in the temperatures range from 0 to 70°C and the pressures range up to 2.45 MPa with an uncertainty of ±0.82 m/s. The measurement results of speed of sound of HFO-1234ze(E) in the liquid phase indicated that the effect of temperature on the speed of sound is greater than that of pressure, and were compared to those calculated from REFPROP. The measurement results are slightly lower than those calculated from REFPROP with a maximum deviation of 1.2%. REFPROP states that speed of sound in HFO-1234ze(E) liquid phase has an uncertainty of 0.2%, so our measurement results are not consistent with those of REFPROP.