Abstract
A constitutive model of helium II is perturbed by a pulsating body force and a pulsating fluid source, both having arbitrary anisotropic distributions. The model is compressible, viscous and heat conducting. The general solution has complex wave-numbers, anisotropic amplitudes and some isotropic features. Long-range decays are spherical and partially-but-dominantly exponential. Viscosity waves form one wave-species found only in the velocity perturbation. Waves of two other species propagate with all perturbations; they each implicate both ordinary and second sounds; those propagating with the velocity perturbation and a generalised velocity perturbation are irrotational waves. When specific heats nearly coincide, those other two wave-species separately approximate ordinary sound and second sound; also, a nonfree perturbation system supports viscosity waves and ordinary sound and weakly supports second sound, while a freelike perturbation system weakly supports ordinary and second sounds; both systems are weakly coupled. Uncoupling occurs with coincidence of specific heats.
