Transient heat transfer in liquid helium is investigated both experimentally and theoretically in plane and cylindrical geometry in the range of parameters where superfluid turbulence appears to be important. The influence of the main flow parameters – heat flux, pulse duration, and rest time – on the temperature evolution is reported. At high heat inputs the mutual friction force related to the superfluid vortex lines leads to the formation of a temperature overshoot behind the propagating second-sound wave and must be looked upon as a macroscopic effect of microscopic quantum turbulence. The experimental results can be reproduced by a theoretical model when the mutual interaction force is expressed in terms of the vortex line density (VLD), and the Vinen equation, extended to include spatial dependence, is taken into account for its temporal evolution. Fair quantitative agreement between experiment and theory is obtained if the ratio of the temperature overshoot and the shock-wave amplitude is below about 4. At stronger heat inputs the agreement is only qualitative.

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