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Simulation and Analysis of Natural Rain in a Wind Tunnel via Digital Image Processing Techniques

Aaron, K. M. and Hernan, M. A. and Parikh, P. and Sarohia, V. and Gharib, M. (1986) Simulation and Analysis of Natural Rain in a Wind Tunnel via Digital Image Processing Techniques. AIAA Papers, 86-0291. American Institute of Aeronautics and Astronautics , New York.

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It is desired to simulate natural rain in a wind tunnel in order to investigate its influence on the aerodynamic characteristics of aircraft. Rain simulation nozzles have been developed and tested at JPL. Pulsed laser sheet illumination is used to photograph the droplets in the moving airstream. Digital image processing techniques are applied to these photographs for calculation of rain statistics to evaluate the performance of the nozzles. It is found that fixed hypodermic type nozzles inject too much water to simulate natural rain conditions. A modification uses two aerodynamic spinners to flex a tube in a pseudo-random fashion to distribute the water over a larger area.

Item Type:Report or Paper (Report)
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URLURL TypeDescription
Gharib, M.0000-0002-2204-9302
Additional Information:This paper is declared a work of the U.S. Government and therefore is in the public domain. This work was carried out at the Jet Propulsion Laboratory, California Institute of Technology under Contract NAS7-918, Task Order RE 65/Amendment 459, jointly funded by NASA Langley Research Center and Goddard Space Flight Center - Wallops Flight Facility (505-45-00-04-59). The authors extend their gratitude to Mr. Earl Dunham Jr., NASA Langley Research Center, and Mr. Edward Melson, NASA Wallops Flight Facility for many valuable technical suggestions throughout the program. The assistance of Mr. R. Smither, Mr. W. Bixler and Mr. S. Kikkert in the design and fabrication of the experimental facilities and in acquisition of the data is greatly appreciated.
Funding AgencyGrant Number
Goddard Space Flight Center505-45-00-04-59
Series Name:AIAA Papers
Issue or Number:86-0291
Record Number:CaltechAUTHORS:20130913-080959226
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:41306
Deposited By: Tony Diaz
Deposited On:17 Sep 2013 20:08
Last Modified:10 Nov 2021 04:28

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