CFD-based simulation of helicopter in shipborne environment

Abstract

The development of High Performance Computing and CFDmethods have evolved to the point where it is possible to simulate complete helicopter configurations with a good accuracy. These capabilities have been applied to a variety of problems such as rotor/fuselage and main/tail rotors interactions, helicopter performance in hover and forward flight, rotor design, etc. The GOAHEAD project is a good example of a coordinated effort to validate CFD for such helicopter configurations. These simulations, however, have been limited to steady flight problems. The present work addresses the problem of simulating manoeuvring flights by coupling the CFD code HMB2 with a versatile multi-body grid motion method and a Helicopter Flight Mechanics (HFM) method. The formulation of the CFD has been adapted to the change in frame of reference used for the calculations. After a discussion of the previous work carried out on the subject and a description of the methods used, validation of the CFD for ship airwake, and rotorcraft at low advance ratio flight are presented. Finally, the results obtained for various test cases using the new method are presented and discussed.