Development of a Pilot Model of Hypersonic Rarefied Wind-Tunnel
نویسندگان
چکیده
A pilot model of the hypersonic rarefied wind-tunnel (HRWT) has been developed and its flow characteristics have been measured. The HRWT consists of a gas heater which produces an increase in working gas temperature, an expansion nozzle with a large expansion ratio, a vacuum chamber as the test section, and an evacuation system with high exhaust velocity to allow a continuous operation at low ambient pressures. The nozzle exit diameter is 100 mm, which enables a quasi-uniform core flow diameter of 10 mm with Knudsen numbers at the order of 0.1 cm−1. The flow characteristics in the test section have been measured with the aid of direct-simulation Monte-Carlo calculations of rarefied flows around the test model.
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