A Brief Overview of Contributions Made by Jack Seiner Based on Collaborative Activities Spanning the past Thirty Years

Abstract

OVERVIEW This commemorative article will provide a brief and informal overview of some of Dr. John M. Seiner’s (Jack’s) key contributions, based largely on collaborative efforts performed over the past thirty years. Such efforts were initially focused on problems related to the understanding and reduction of jet noise, but later encompassed a number of other aero-acoustic and propulsive problem areas. At the NASA Langley Research Center (LaRC), Jack was instrumental in developing the Jet Noise Laboratory (JNL) and its anechoic test facility. He was head of the JNL for a number of years prior to his retirement from NASA. During his LaRC years (1974-1998): Jack developed test facilities as well as innovative testing and diagnostic techniques for studying high speed jets; he provided unique insights into the understanding of high speed jet noise mechanisms and the methodology to be used to predict noise emission; and, he provided the jet noise community with a significant number of archival data sets. He also made major contributions to ongoing NASA jet noise reduction programs such as the High Speed Research (HSR) program, and he was also involved in activities related to jet/laser interactions and installation effects, as well as to varied problems involving turbulent mixing control and mixing enhancement. After leaving NASA in 1998, Jack became associate director, and then director of the National Center for Physical Acoustics (NCPA) at the University of Mississippi in Oxford. He was tasked with expanding the NCPA’s activities to encompass aeroacoustic and related problems of interest to the Department of Defense (DOD). At the NCPA, Jack and coworkers (a number of whom had been part of his JNL team at NASA - Bernie Jansen, Mike Ponton, and Larry Ukeily) designed a state-of-the art 12” trisonic tunnel for aero-acoustic testing up to Mach 5, and they developed an anechoic test chamber comparable to the one operational at the LaRC. Jack’s research activities at the NCPA had a DOD emphasis and involved work in areas such as weapons bay cavity aeroacoustics, missile aero-propulsion, and aero-optics/turbulence control, as well as more traditional jet noise reduction research activities, which now became focused on Military Fighter Aircraft.