Implementation of a Body Force Model in OVERFLOW for Propulsor Simulations

Speaker: Dogus Akaydin, Science and Technology Corporation / NASA Ames Research Center
October 31, 2017

Presentation

Abstract

In order to improve fuel efficiency of commercial airplanes, NASA pursues a variety of advanced airframe and propulsion aircraft concepts, such as boundary layer ingestion (BLI). Due to NASA's support on the concepts such as D8 and STARC-ABL that feature BLI, modeling aircraft engines and propulsors with BLI has gained importance. We will present our implementation of a recent propulsor model into NASA's workhorse CFD code OVERFLOW to improve modeling fidelity of aircraft concepts with BLI propulsors. This propulsor model estimates the forces imparted on the fluid by the blade camber surfaces as body force source terms in the momentum and energy equations over grids that represent the rotor and stator of a fan stage. We tested our implementation on three cases: 1) Source Diagnostics Test (SDT) fan with R4 rotors which has extensive test data on aerodynamic performance and rotor wake surveys, 2) A stand-alone Aeronaut TF8000 propulsor which is an off-the-shelf propulsor used on model aircraft, 3) The D8 aircraft model placed in a wind tunnel with boundary-layer ingesting TF8000 propulsors. In the case of SDT, the model predicted the average flow speed and total pressure rise through the SDT propulsor within a few percent of the LDV (Laser Doppler Velocimetry) measurements. In the case of the D8 aircraft with TF8000 propulsor, the body force model provided detailed insights on aerothermodynamics and aeromechanics effects of the boundary layer ingesting propulsor; these insights could not have been obtained by using the uniform pressure jump model.

Biography

H. Dogus Akaydin works as a research engineer with the Science and Technology Corporation (STC), working in the Computational Aerosciences Branch of the NASA Advanced Supercomputing Division at NASA Ames Research Center. Akaydin contributed to various projects such as Krueger flap design for the Hybrid Wing Body aircraft, aeroelastic analysis of the VCCTT (various camber continuous trailing edge) wing concept, and more recently, the development of the D8 aircraft. Before joining the STC in late 2013, Akaydin was a postdoc at Center for Turbulence Research at Stanford University. He received his B.Sc. and M.Sc. degrees in aeronautical engineering from Istanbul Technical University and his Ph.D. degree in mechanical engineering from the City University of New York on development of flow-powered piezoelectric energy harvesters.

Seminar Participation

Attending In Person

For select seminars, you may wish to attend in-person if you are in the vicinity of NASA Ames Research Center. These AMS seminars are held in Building N258 in Room 127, just off the front lobby. Sessions available to attend in-person will be indicated in the announcement information. In-person participants without NASA badges will need a valid visitor badge (US citizenship or permanent residency is required) to enter the facility.

Join Us Online

To attend an AMS seminar, click on the Microsoft Teams link in the seminar description. You can connect through the desktop Teams App if you have it, or you can select "Watch on the Web Instead" to enter the meeting as a guest. Please ensure that you've muted your microphone in Teams before you select "Join Now" to enter the meeting lobby.