Improving Phased Array Measurement Techniques and Jet Noise Understanding.

摘要

This first interim report summarizes the progress made toward advancing 'synthetic phased array' technology to improve understanding of noise in hot supersonic jets. This technology, initially developed in a previous NASA SBIR project for trailing edge noise, will be applied to improve beamforming analysis methods, facilitate the design of more effective microphone arrays, and significantly enhance the understanding and characterization of noise sources from supersonic jets. The work accomplished this period is primarily of a foundational nature for our future efforts: 1) Contracts have been put in place to allow all of our collaborators to participate in the work. 2) Accounts have been obtained on a number of DoD HPC resources and computer time allocated for use on this project. 3) An initial run of an over-expanded jet issuing from a military-style nozzle has been conducted in order to provide verification that ITAC's version of the CHOPA solver, when run on the HPC systems, is obtaining consistent results to those obtained earlier by Penn State. 4) Data has been obtained from Prof. Morris's group at Penn State from earlier simulations of both a nearly perfectly expanded jet and the over-expanded jet case. 5) A new version of the PSU-WOPWOP Ffowcs Williams-Hawkings solver has been obtained from Prof. Brentner. This version requires much less memory, fixes important bugs, and runs faster than previous versions. As a result of the above efforts, the project is in a good position to make significant progress in the next period.