Development of a superfluid shock tube facility

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The objectives of this research are the development of the superfluid shock tube facility which is a multi-purpose general experimental facility for shock wave and thermo-fluid dynamic phenomena in superfluid helium. In addition, several relating experimental studies have been also conducted by using the facility.(1) The design and manufacturing of the facility and shock performance test have been completed. The test with superfluid helium in the low pressure section of the shock tube demonstrated that the shock performance is quite satisfactory for a wide variety of scientific and engineering experiments.(2) Study of second sound thermal shock waves by visualization method of laser holography interferometer and by using superconductive temperature sensors : The propagation and the pulse form deformation due to the breakdown of superfluidity are investigated to yield valuable information on the development of high density quantized vortex on a heater and behind a thermal shock and high … More ly transient heat transfer in He II.(3) Study of evaporation phenomena induced by the direct incidence of a thermal pulse on a free surface of He II both experimentally and by numerical computation : A propagating evaporated vapor wave is clearly visualized in the form of an interferogram. The reflection law of a second sound thermal shock wave from a free surface is experimentally obtained and affirmatively compared with Khalatnikov's theory. An attempt to modify the conventional laser holography interferometer to a two-beam laser holography interferometer was made for a higher resolution of interferograms.(4) Numerical simulation of superfluid thermo-fluid dynamic phenomena on the basis of the two-fluid equation system supplemented with the equation of vortex line density development proposed by Vinen : The initial value of the vortex line density and the source term of the VInen equation are investigated by comparing the result with experimental ones. A scheme for two-dimensional analysis is successfully developed and applied to a problem of a thermal shock wave reflection on a two-dimensional wedge.(5) The validity of the facility is discussed to conclude that the facility can be used for the various experiments anticipated. Some modification are also suggested for the higher performance and easy operation. Less