We describe the principles, techniques, and performance of acoustic resonators used to measure the shear viscosity, the thermal conductivity, and the bulk viscosity in gases. We developed the Greenspan acoustic viscometer at NIST, where colleagues used it to measure the shear viscosity of 16 industrial surrogate and process gases with an uncertainty of 0.5%. We designed and used a novel hybrid resonator to measure the bulk viscosity and dispersion in xenon on the critical isochore much closer to the liquid-vapor critical point than ever before. We discuss the difficulties in acoustic measurements of the thermal conductivity of gases and propose possible solutions.
Transport Properties of Fluids A: Advances in Transport Properties
Royal Society of Chemistry Publishing, Cambridge, -1
transport properties, shear viscosity, thermal conductivity, bulk viscosity, acoustic techniques