THE PROPAGATION OF N WAVES THROUGH TURBULENCE - AN EXPERIMENTAL-STUDY

a model experiment to study the effect of atmospheric turbulence on so nic booms is reported. The model sonic booms are N waves produced by e lectric sparks, and the model turbulence is created by a plane jet. Th e important parameters are the waveform, peak pressure, and rise time because they determine the annoyance caused by sonic booms. Our experi ment was designed so that the scale factor (approximately 10(-4)) rela ting the model turbulence to atmospheric turbulence was the same as th at relating the model N waves to sonic booms. Results are reported for plane waves and are as follows. 1. The model experiment successfully simulates sonic boom propagation through the atmosphere. 2. Passage th rough turbulence almost always causes rise time to increase. 3. Averag e rise time is always increased by turbulence. 4. Average peak pressur e is always decreased by turbulence.