ABSTRACT
The presence of dissipative processes in a superfluid leads to absorption or damping of sound. In order to investigate the question of sound propagation in the presence of dissipation let us write the general equations, 9-13 to 9-16, in the following linearized form: () ρ ˙ + div j = 0 https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429502897/20d72e0b-9d39-4175-acc6-a943547edf8a/content/eq370.tif"/> () j . i + ∂ p ∂ r i = η ∂ ∂ r k ( ∂ v ni ∂ r k + ∂ v nk ∂ r i − 2 3 δ ik ∂ v n ℓ ∂ r ℓ ) + ∂ ∂ r i { ζ 1 div ( j − ρ v n ) + ζ 2 div v n } https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429502897/20d72e0b-9d39-4175-acc6-a943547edf8a/content/eq371.tif"/> () v . S + ∇ μ = ∇ { ζ 3 div ( j − ρ v n ) + ζ 4 div v n } https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429502897/20d72e0b-9d39-4175-acc6-a943547edf8a/content/eq372.tif"/> () T { ( σ ρ ) + σ ρ div v n } = κ Δ T https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429502897/20d72e0b-9d39-4175-acc6-a943547edf8a/content/eq373.tif"/>
