Measurements and Simulation of Ori ce Flow for Micropropulsion Testing
نویسندگان
چکیده
Numerical and experimental results for a rare ed gas expansion through a thin circular ori ce are presented. The ori ce owwas used as a calibrationtest for a torsional thrust standdesigned tomeasure force levels from10¡6 to 10¡3 N. Molecular nitrogen, argon, and helium at room temperature are used as test gases. The mass ux and thrust measurements are compared with the direct simulationMonte Carlo results for Knudsen numbers from 40 to 0.01and plenum to facility backgroundpressure ratios of 103¡107. Factors that affect the total propulsive force, such as jet back ow and facility background gas penetrating the jet, are analyzed. The measured and calculated mass ux and total propulsive force were found to agree well for Knudsen numbers less than 1.
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تاریخ انتشار 2003