Kim, Jin O.Wang, YuzhouBau, Haim H.2023-05-222023-05-221991-03-012010-08-16https://repository.upenn.edu/handle/20.500.14332/39917The effects of an adjacent fluid's viscosity and density on the characteristics of torsional stress waves transmitted in a waveguide with a circular cross section are studied theoretically and experimentally. Expressions for the torsional waves speed, dispersion relations, and attenuation are obtained as functions of the adjacent fluid's viscosity and density. The theoretical results are compared with experimental observations. It is demonstrated that a devices similar to the one described herein can be used as a rugged, real-time, on-lines sensor for measuring the viscosity of a fluid with a known density. Such a sensor can measure the viscosity of fluids with a density viscosity product (ρfμ) greater than 100kg2/m4s to a precision of 1% or betterEngineeringMechanical EngineeringArticle