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Heat Transfer Prediction in Transitional Hypersonic Flow

Award Information

Agency:
Department of Defense
Branch:
Air Force
Award ID:
Program Year/Program:
2011 / STTR
Agency Tracking Number:
F08B-T13-0044
Solicitation Year:
2008
Solicitation Topic Code:
AF08-BT13
Solicitation Number:
2008.B
Small Business Information
Cascade TechNologies, Inc.
2445 Faber Place Suite 100 Palo Alto, CA 94303-3347
View profile »
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
 
Phase 2
Fiscal Year: 2011
Title: Heat Transfer Prediction in Transitional Hypersonic Flow
Agency / Branch: DOD / USAF
Contract: FA9550-10-C-0174
Award Amount: $750,000.00
 

Abstract:

ABSTRACT: Predicting the wall heat loading experienced by hypersonic vehicles during the transition from laminar to turbulent boundary layer flow is the grand-challenge tackled by the present proposal. Previous studies have not focused completely on this phenomenon. In this work we adopt high-fidelity numerical simulations (Direct Numerical Simulation, DNS) to shed some light on the problem, with the objective of obtaining a detailed statistical description of the physical phenomena relevant to the transitional region. The focus is on the dynamics of large-scale structures and the turbulence characteristics in this highly intermittent region. In Phase I we demonstrated, the existence of a potential flow mechanism for the local overshoot behavior. The overall goal of the project is to develop a physics-based engineering model that correctly represents the heating profile during transition. This model aims at directly representing the modified turbulent energy redistribution process that is active in the transitional region due to highly non-equilibrium effects. DNS computations will provide insight into the transition region, by identifying the connection between wall heating peaks, localized Reynolds stresses and coherent vortical structures. preliminary engineering model developed for the flow over a flat plate will further be tested, and extended. BENEFIT: The outcome of the project is an add-on tool that will be implemented seamlessly within commercial CFD environments and can , therefore, directly be used by designers and analysis. The effort of establishing cause/effect relationships that lead to the heat-transfer overshoot within the transition region, and the subsequent validation of the predictive capabilities, will also offer confidence regarding design choices.

Principal Investigator:

Shoreh Hajiloo
General Manager
(650) 521-0243
hajiloo@turbulentflow.com

Business Contact:

Parviz Moin
Founder
(650) 521-0243
moin@turbulentflow.com
Small Business Information at Submission:

Cascade Technologies Incorporated
2445 Faber Place #100 Palo Alo, CA 94303-

EIN/Tax ID: 043353686
DUNS: N/A
Number of Employees:
Woman-Owned: No
Minority-Owned: No
HUBZone-Owned: No
Research Institution Information:
Stanford University
Office of Sponsored Research
320 Panama Street
Stanford, CA 93305-
Contact: Catherine Boxwell
Contact Phone: (650) 725-6864