Cfd Grid Generation And Flow Analysis Of A Counter Rotating Open Rotor Propulsion System

CFD Grid Generation and Flow Analysis of a Counter Rotating Open Rotor Propulsion System

Abstract: Counter Rotating Open Rotor (CROR) systems promise a light weight, fuel efficient means for propulsion for the aerospace industry. The only drawback is its high level aerodynamic noise, which could be analyzed using Computational Aeroacoustic (CAA) methods such as FW-H or AIBM. However, for a better performing CAA tool, a good CFD model and flow solution is first needed. This study focuses on creating both structured and unstructured meshes for two CROR configurations, one with 12x12 blades count and the other with 12x10 count. Three unstructured CFD mesh domains, with varying domain sizes and differing boundary conditions, were solved in FLUENT for a normal sea-level take-off condition for the CROR, with a flow mach number M = 0.2, and compared to each other to see which one is a better fit for accurate flow solutions with less computation time. The results showed that the most suitable CFD model for aerodynamic noise analyses is the single passage unstructured mesh, with periodic boundary conditions and a domain breadth or radius that is about ten times larger than the mean rotor radius. Furthermore, the CFD model developed in this study is also perfectly suitable for any further CAA investigation in order to reduce noise of the CROR.

New Results in Numerical and Experimental Fluid Mechanics IX

This book presents contributions to the 18th biannual symposium of the German Aerospace Aerodynamics Association (STAB). The individual chapters reflect ongoing research conducted by the STAB members in the field of numerical and experimental fluid mechanics and aerodynamics, mainly for (but not limited to) aerospace applications, and cover both nationally and EC-funded projects. By addressing a number of essential research subjects, together with their related physical and mathematics fundamentals, the book provides readers with a comprehensive overview of the current research work in the field, as well as its main challenges and new directions. Current work on e.g. high aspect-ratio and low aspect-ratio wings, bluff bodies, laminar flow control and transition, active flow control, hypersonic flows, aeroelasticity, aeroacoustics and biofluid mechanics is exhaustively discussed here.

NASA Technical Memorandum