Multi-Domain Model for Rotorcraft Countermeasure Dispensing

A multi-domain Eulerian/Lagrangian approach for modeling transient behavior of countermeasures released from tactical rotorcraft is being developed, that tracks chaff/flares/pyrophorics properties from initial dispensing and bloom, through entrainment within the rotorcraft flowfield, to final settling to the ground. Development of the software leverages extensive prior simulation and experimental work conducted at CDI on droplet and particle modeling, fuel jettisoning, agricultural airborne spraying applications, icing accretion, brownout cloud simulation, and store separation clearance determination. The software is designed for supporting applications that include chaff dispenser mounting design, piloted simulation training and tactics development, and radar cross-section (RCS) determination and engagement simulations. The code couples in CDI's real-time free wake analysis to support the development of accurate time-varying signature calculations and expands the potential for analysis of tactics and doctrine for countermeasure dispensing in both steady and maneuvering rotorcraft flight conditions.