EXPERIMENTAL TESTING OF PRESSURE PULSE PROPAGATION IN NON-NEWTONIAN SIMULANTS WITH A VOID FRACTION OF NON-CONDENSABLE GAS

摘要

This paper describes experimental work performed in support of the Hanford Tank Waste Treatment and Immobilization Plant (WTP) to quantify the propagation and attenuation of pressure pulses as they move through piping systems filled with quiescent non-Newtonian simulants that support a void fraction of non-condensable gas. A subset of experimental results is presented in this paper and is shown to compare favorably to theoretical expectations. In general, the rate of attenuation of the propagating pulse increases with void fraction, pulse peak pressure, and the inverse of pulse duration, all a consequence of rarefaction wave accumulation at the shock front. The data developed from this experimental test program is supporting the development and validation of related analytical and numerical (CFD) models. These models are being developed with the practical objective of determining the length over which a pressure pulse propagating from an ignition event in a gas pocket remains structurally significant to piping at the WTP. In addition to selected results and key conclusions, specific aspects of test preparation and conduct are discussed in this paper including the generation of pressure pulses with a mechanical impact at the liquid surface; the development of a well-dispersed gas phase (i.e., void fraction) using catalyzed decomposition of hydrogen peroxide in the simulant mixture; the retention of a void fraction by using mixtures with non-Newtonian (i.e., Bingham plastic) properties; and the in situ measurement of void fraction.