Enhancement and Optimization of a Lobed Mixer for AAAV

CFDRC proposes to reduce the thermal and acoustic signatures of the AAAV engine exhaust with a minimal loss in installed engine performance by designing, optimizing and testing a passive, lobed mixer/ejector system. A design, analysis and test cycle based upon accurate and validated Computational Fluid Dynamics analyses, parametric design optimizations and detailed testing is proposed to reduce the detectable thermal and acoustic signatures. During Phase I our efforts will focus on isolated ejector analyses and tests that will be used to assess enhancements to the lobed mixer. This will be expanded during Phase II by optimization of the installed mixer system performance and signature reduction via consideration of flow features upstream and downstream of the mixer for various engine operating conditions and environments. The AAAV design currently incorporates an untested and uncharacterized, passive, lobed mixing device that conditions engine exhaust flow to reduce the thermal and acoustic signatures. The proposed work will characterize the existing system, and at completion of Phase II, result in an optimized design that reduces the thermal and acoustic signatures without significant impact on space, weight and power. CFDRC has applicable experience assisting GDLS in the design and analysis of such systems for other combat vehicles.