TY - GEN
T1 - Streamwise development and turbulence characterization of a twin-vortex inlet distortion for turbofan applications
AU - Guimarães, Tamara
AU - Frohnapfel, Dustin J.
AU - Todd Lowe, K.
AU - O'Brien, Walter F.
N1 - Funding Information:
The authors would like to acknowledge the National Institute of Aerospace (NIA) and NASA Langley Research Center for funding this work in association with NASA's Environmentally Responsible Aviation Project (NIA cooperative agreement RD-2917), project managers Fay Collier (LaRC), Hamilton Fernandez (LaRC), Greg Gatlin (LaRC), and Bo Walkley (NIA). The authors would like to additionally thank Boeing Research and Technology Company (POCs: John Bonnet and Ron Kawai) and CAPES for financial support of Tamara Guimarães.
PY - 2017
Y1 - 2017
N2 - Ground based turbofan inlet flow distortion investigations typically involve a distortion generator placed within the inlet duct to create the desired flow conditions entering the fan. The physical nature of such devices requires thorough research and analysis to ensure that any adverse effect of the test article does not interfere with or disturb the desired test conditions. A sub-scale wind tunnel experiment was conducted to study the nature of the distortion development and characterize the turbulent energy produced by a twin-vortex StreamVaneTM swirl distortion generator. Stereoscopic particle image velocimetry was employed to measure the three component velocity field at four discrete planes downstream of the StreamVane. Time-averaged results revealed that secondary flow angles decreased by as much as 25% while the centers of the twin vortex distortion pattern convected toward the centerline of the duct. Maximum secondary flow velocity magnitudes remained nearly constant in the outlet flow; however, an increase in the extent of the distortion was observed. Statistical time-resolved results indicated that a highly non-uniform turbulent flow field, with axial turbulence intensity levels exceeding 7%, was produced in the immediate downstream measurement plane; further downstream, the turbulent energy mixed to a relatively uniform intensity of approximately 4%. A POD description of the flow indicated that the turbulent length scales produced by the StreamVane wakes attenuate as the flow develops and mixes. All results from this investigation will assist in understanding the effects of submerged distortion generators as well as advance the current state of the art toward less disruptive flow conditioning devices.
AB - Ground based turbofan inlet flow distortion investigations typically involve a distortion generator placed within the inlet duct to create the desired flow conditions entering the fan. The physical nature of such devices requires thorough research and analysis to ensure that any adverse effect of the test article does not interfere with or disturb the desired test conditions. A sub-scale wind tunnel experiment was conducted to study the nature of the distortion development and characterize the turbulent energy produced by a twin-vortex StreamVaneTM swirl distortion generator. Stereoscopic particle image velocimetry was employed to measure the three component velocity field at four discrete planes downstream of the StreamVane. Time-averaged results revealed that secondary flow angles decreased by as much as 25% while the centers of the twin vortex distortion pattern convected toward the centerline of the duct. Maximum secondary flow velocity magnitudes remained nearly constant in the outlet flow; however, an increase in the extent of the distortion was observed. Statistical time-resolved results indicated that a highly non-uniform turbulent flow field, with axial turbulence intensity levels exceeding 7%, was produced in the immediate downstream measurement plane; further downstream, the turbulent energy mixed to a relatively uniform intensity of approximately 4%. A POD description of the flow indicated that the turbulent length scales produced by the StreamVane wakes attenuate as the flow develops and mixes. All results from this investigation will assist in understanding the effects of submerged distortion generators as well as advance the current state of the art toward less disruptive flow conditioning devices.
UR - http://www.scopus.com/inward/record.url?scp=85028524450&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85028524450&partnerID=8YFLogxK
M3 - Conference contribution
AN - SCOPUS:85028524450
SN - 9781624105111
T3 - 53rd AIAA/SAE/ASEE Joint Propulsion Conference, 2017
BT - 53rd AIAA/SAE/ASEE Joint Propulsion Conference, 2017
PB - American Institute of Aeronautics and Astronautics Inc, AIAA
T2 - 53rd AIAA/SAE/ASEE Joint Propulsion Conference, 2017
Y2 - 10 July 2017 through 12 July 2017
ER -