Experimental investigation of second sound shock waves in liquid helium II

by Rogers, Philip Louis

Abstract (Summary)
Second sound shock waves in liquid helium II were studied experimentally using superconducting thin film detectors. The temperature waves were generated electrically using an evaporated thin film heater and the effects of variations in pulse power (input power to the heater as large as 150 Watts/cm(2)) and pulse duration (from less than 100 µsec to 10 msec) were examined. A number of different materials were tested for use as detectors with the best results obtained from evaporated gold on tin. Qualitative agreement with Khalatnikov's theory was obtained; however, breakdown of the theoretical model was observed for heater input powers greater than 20 - 30 Watts/cm(2), in agreement with other known results. Quantitative data for shock strength, i.e., temperature amplitude, wave speed, and pulse power, were obtained. The critical counterflow velocities calculated from these data, w = 2.51 to 3.77 m/sec, indicate that heat fluxes at least an order of magnitude greater than those reported for steady channel flow can be transported using the pulsed techniques.
Bibliographical Information:

Advisor:Hans Wolfgang Liepmann

School:California Institute of Technology

School Location:USA - California

Source Type:Master's Thesis



Date of Publication:10/13/1978

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