NASA SBIR 2003 Solicitation


PROPOSAL NUMBER: 03- II A4.06-8071
SUBTOPIC TITLE: Launch Vehicle Subsystems Technology
PROPOSAL TITLE: Rule-Based Multidisciplinary Tool for Unsteady Reacting Real-Fluid Flows

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Siddharth Thakur
3221 NW 13th Street, Suite A
Gainesville, FL 32609-2189
U.S. Citizen or Legal Resident: Yes

Loci-STREAM is a CFD-based, multidisciplinary, high-fidelity design and analysis tool resulting from Phase I work whose objectives were: (a) to demonstrate the feasibility of implementing a reacting-flow pressure-based algorithm in the Loci framework, and (b) to test the robustness of a real-fluid methodology in the pressure-based framework. Loci is a rule-based programming framework which automatically handles parallel computing and provides for easy integration of multidisciplinary physics. Key current capabilities of Loci-STREAM are: (i) all-speed formulation, (ii) generalized grids, (iii) distributed memory parallel computing capability, (iv) finite rate chemistry, and (v) steady and unsteady turbulent flow capability. Phase II work will enhance Loci-STREAM and make it a reliable and practical simulation tool by incorporating the following into it: (1) high-resolution discretization schemes, (2) conjugate heat transfer, (3) real-fluid modeling, (4) efficient operator-splitting for stiff chemistry, (5) robust time-stepping, (6) improved turbulence models for unsteady flows, and (7) coupling with solid stress analysis. It is anticipated that the above capabilities coupled with smaller memory requirements of the pressure-based methodology embedded in Loci-STREAM will make computations of complex problems encountered in thrust chamber assemblies of rocket engines such as multi-element injector flows requiring large grids (100 million nodes or more) a reality.

Potential commercial applications of Loci-STREAM are wide-ranging. The reacting flow capability can be used for simulating combusting flows in various industries, such as the gas turbine industry. The unsteady flow capability can be used in the oil & gas industry (e.g., vortex shedding past platform risers) and the turbomachinery industry (e.g., hydraulic turbines, fans, compressors). The real-fluids methodology can be used in a large number of industrial flow situations involving both chemically inert and reacting flows (e.g., cryogenic flows). With future additions of other combustion, cavitation and multi-phase models, the applicability of Loci-STREAM can be further broadened.

Near-term NASA applications include:
(a) multi-element injector flows along with fuel and oxidizer feedlines and manifolds, coupled with conjugate heat transfer and modeling of pressure and thermally induced stresses in the solid region of the regenerative circuits.
(b) lift-off debris transport for space shuttle launch problem, which involves range of flow speeds from quiescent to Mach 6 and grids with more than 75 million points.
(c) reacting rocket engine exhaust plumes and discharge and/or combustion of hot O2 or H2 from rocket engine components during ground testing.
(d) flow of supercritical fluids through valves and run tanks.