NEAR NOISE FIELD OF A JET-ENGINE EXHAUST I - SOUND PRESSURES

摘要

The acoustical near field produced by the exhaust of a stationary turbojet engine having a high pressure ratio was measured for a single operating condition without afterburning. The maximum over-all sound pressure without afterburning was found to be about 42 pounds per square foot along the jet boundary in the region immediately downstream of the jet-nozzle exit. With afterburning the maximum sound pressure was increased by 50 percent. The largest sound pressures without afterburning were obtained in the frequency range from 350 to 700 cps.