title: Thermoacoustic waves along the critical isochore.
abstract: Near the liquid-gas critical point, thermal disturbances can generate sounds. We study the acoustic emission over four decades of reduced temperatures [defined as ɛ=(T-T(c))/T(c), with T(c) the critical temperature] along the critical isochore, under linear and nonlinear temperature perturbations, respectively. We identify various thermoacoustic behaviors by numerically solving the governing equations. It is shown that a homogeneous thermoacoustic-wave pattern dominates in the linear case, largely independent of ɛ; whereas under the nonlinear perturbation, variation in ɛ could lead to severe wavefront deformation. The strong nonlinear effect is found to be of a transient nature because, in due time, both cases tend to converge in terms of the energy yield of the adiabatic process.
authors.affiliation: Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: B
authors.initials: B
authors.lastname: Shen
authors.forename: P
authors.initials: P
authors.lastname: Zhang