Turbulent drag reduction across Mach regimes: Combining DNS and systems theory to analyze and design
Abstract
Most Naval weapons systems must operate in turbulent flow environments spanning a range of Mach numbers. Patterned riblet surfaces o,ffer a simple means of improving performance in these systems across the operating envelope. When appropriately designed, riblets ca,n reduce drag, modulate heat fluxes, enhance endurance, and increase range in these systems. The objective of the proposed research, is to characterize the complex fluid dynamics of turbulent flows over patterned riblet surfaces for a range of Mach regimes. To thi,s end, we propose to combine direct numerical simulations (DNS) with emerging systems-theoretic analysis and design tools to better, understand the physical processes underlying these performance benefits. DNS will be performed to investigate compressible boundary, layer turbulence over at plates and axisymmetric geometries with surface patterning. Systems-theoretic analysis tools will be devel,oped and used to dissect the governing equations for compressible turbulence and to discover physical mechanisms responsible for dra,g reduction and heat transfer. This research builds on resolvent analysis of low-speed incompressible flows over riblets and its non,linear extensions, which will be extended to compressible turbulence across Mach regimes, from low subsonic to hypersonic. These sam,e systems-theoretic tools will be used to perform systematic design optimizations of riblet patterns, which will be validated within, DNS and used to guide further investigation of the large parameter space.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 14, 2022
- Source ID
- N000142212029
Entities
People
- Maziar S. Hemati
Organizations
- Office of Naval Research
- Regents of the University of Minnesota
- United States Navy