Prediction of the CF-18/MK-83 LD Store Separation Characteristics Using a Quasi-Steady CFD Approach

Abstract

This paper presents the results of a numerical simulation of an actual store separation case. These results are the achievement of a collaborative effort between the Institute for Aerospace Research (IAR) of the National Research Council Canada (NRC) and Bombardier Aerospace. The purpose of this collaboration is to evaluate a quasi-steady CFD approach, developed at NRC/IAR for stores carriage and release problems, and to validate the trajectory predictions with the flight test data. This numerical approach is based on unstructured moving grid technology. The specific store configuration under analysis is the release of a single low-drag MK-83 LD store from the Vertical Ejection Rack (carrying a second MK-83 LD) underneath the wing of the CF18 aircraft. The same configuration was flight tested at the Aerospace Engineering Test Establishment (AETE) in Cold Lake, Alberta, Canada, and the flight test data are used to validate the CFD predictions. Despite the fact that the time required for a full trajectory simulation needs to be decreased, it has been established that the NRC/IAR quasi-steady CFD approach possesses the necessary capabilities to predict complex flow fields around realistically challenging aircraft/stores configurations. Thus, it can be used to compute the loads on a store and, consequently, the store’s trajectory with a good engineering accuracy.