It is shown that vortex-line-density fluctuations in counterflowing He II can be greatly enhanced by modulating the heater with a noise generator. This technique is used to test Vinen's equation for vortex-line turbulence. Vinen's equation, linearized to describe fluctuations, appears to be correct except near the lambda transition.

• Received 26 February 1982

DOI:https://doi.org/10.1103/PhysRevLett.48.1187