Measurement of pressure wave speed in stainless-steel pipe generated by water hammer

Abstract

This paper aims to demonstrate a measurement method of pressure wave speed in stainless-steel pipe filled with water caused by water hammer phenomenon. The pressure wave is generated using a self-developed drop impact testing equipment. An impactor is dropped to collide a buffer which then induces the water hammer phenomenon. The generated pressure and its propagation speed in the water are carefully measured here. Pressure measurement is conducted by a pressure transducer, while pressure wave speed is measured by two methods, which utilize peak time of the pressure recorded by pressure transducer and peak time of strains recorded by two strain gages positioned in a different location. These strain gages are oriented to the circumferential direction of the pipe. Measurement result shows that at 1.5 m height, impact pressure of between 0.86 to 1.16 MPa and wave velocity of 1250 m/s were obtained. From the experimental results, the characteristic of pressure wave in the water was able to be observed.