Liquid—Vapor Equilibrium in the System Normal Hydrogen—Helium

Liquid—vapor equilibrium phase compositions for the binary system normal hydrogen—helium have been determined for 11 isotherms in the range 15.50°—32.50°K and at pressures up to 500 psia. The vapor recirculation method of obtaining equilibrium was used in conjunction with a liquid hydrogen vapor—pressure controlled cryostat. Analyses were made on a mass spectrograph. The results are presented in both tabular and graphical form, and the general behavior of the system discussed. An agreement with some previous investigations is demonstrated, and conflicts in existing data are resolved. Some problems of theoretical correlation of the data are discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71182/2/JCPSA6-40-5-1390-1.pd

Towards an Airframe Noise Prediction Methodology: Survey of Current Approaches

In this paper, we present a critical survey of the current airframe noise (AFN) prediction methodologies. Four methodologies are recognized. These are the fully analytic method, CFD combined with the acoustic analogy, the semi-empirical method and fully numerical method. It is argued that for the immediate need of the aircraft industry, the semi-empirical method based on recent high quality acoustic database is the best available method. The method based on CFD and the Ffowcs William- Hawkings (FW-H) equation with penetrable data surface (FW-Hpds ) has advanced considerably and much experience has been gained in its use. However, more research is needed in the near future particularly in the area of turbulence simulation. The fully numerical method will take longer to reach maturity. Based on the current trends, it is predicted that this method will eventually develop into the method of choice. Both the turbulence simulation and propagation methods need to develop more for this method to become useful. Nonetheless, the authors propose that the method based on a combination of numerical and analytical techniques, e.g., CFD combined with FW-H equation, should also be worked on. In this effort, the current symbolic algebra software will allow more analytical approaches to be incorporated into AFN prediction methods

Liquid-vapor equilibrium in the system normal hydrogen-helium : final report

http://deepblue.lib.umich.edu/bitstream/2027.42/7709/5/bad3774.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/7709/4/bad3774.0001.001.tx

Liquid-vapor equilibrium in the system hydrogen-helium : final report

http://deepblue.lib.umich.edu/bitstream/2027.42/7708/5/bad2223.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/7708/4/bad2223.0001.001.tx