Heat Transfer in Superfluids Effect of Gravity.pdf

4 0 0 2 Heat Transfer in Superfluids: Effect of Gravity y a M L.A.Melnikovsky∗ 9 1 ] Abstract t f We discuss the influence of an external field on energy transport in o superfluid. He-II is not isothermal in presence of Earth gravity; instead, s . it supports finite temperature gradient given by a Fourier-like equation. t a We calculate asymptotic behavior of the effective heat resistance in the m vicinity of the λ-transition. - d n 1 INTRODUCTION o c Superfluid is known to be (and it was originally referred to as) a super-heat- [ conductor. The heat in superfluid is transfered by the normal flow. This is 1 fundamentally different [1] from the Fourier law thermal conduction in ordinary v liquids. Instead, it has a nature of convection. In uniform superfluid the flow 0 5 (and the heat transfer) is dissipationless, i.e., it happens at constant tempera- 4 ture. 5 Experimentally observed dissipation in bulk uniform superfluid (i.e., when 0 the friction with walls is neglected) is believed to be due to the vortex creation. 4 This scenario leads to the temperature gradients with complicated nonlinear 0 dependence on the supported heat flux. We show that gravity can also explain / t this dissipation. a m Earth gravity, like any external field,