Uncertainty-based computational robust design optimisation of dual-thrust propulsion system

Abstract

2012) Uncertainty-based computational robust design optimisation of dual-thrust propulsion system, Journal of Engineering Design, 23:8, 618-634, This paper proposes a robust design optimisation methodology for performance evaluation of high-fidelity propulsion systems under both aleatory and epistemic uncertainties. In this paper, uncertainty-based robust design methodology is applied using first-order orthogonal design to estimate worst case of the uncertainties. The effectiveness and computational efficiency of proposed formulation is obtained by decoupling computation of both types of uncertainties in the optimisation process loop. The system robustness is measured by directly minimising the variance of target mean and standard deviation and adhering to performance constraints. A parametric sensitivity analysis of performance parameters due to input parameters variations is also performed to identify the most significant design variables. A hybrid genetic algorithm and simulated annealing approach are used as an optimiser. By using the proposed method, the objective function to maximise the booster phase to sustain phase thrust ratio and total impulse could be achieved while adhering to the motor performance constraints to provide an insensitive solution.

Pressure Profile Prediction of Dual‐Thrust Rocket Motors under Uncertainties

“…(1) Geometric uncertainty: -Nozzle critical diameter is expressed according to Equation (3). The values of E r and t del are treated as uncertain.…”

“…In their paper [3], they investigated the uncertainties in design parameters (geometric uncertainties). Instead of tackling the sources of uncertainties, the goal of this study was mainly to find a model that is insensitive to resulting variations.…”

“…Raza and Liang [3][4][5] conducted a set of design optimization studies for the 3D grain of a dual thrust solid rocket motor under uncertainties. In their paper [3], they investigated the uncertainties in design parameters (geometric uncertainties).…”

Analytical Prediction of Dual-Thrust Rocket motors under Uncertainties

“…To the authors' knowledge of the open literature, handling the aspects of uncertainties has not drawn much attention from the researchers. Recently, Raza and Liang investigated this issue in dual thrust rocket motors in a number of studies [5][6][7]. In these studies, genetic algorithm was used to optimize the accuracy and robustness of a theoretical prediction tool.…”

“…Focus was made on the pressure exponent; a single governing factor of the propellant rate of burning. In [6,7], Raza and Liang focused on the geometric uncertainties of the dual thrust grain. Motivated by the clear shortage of knowledge, the present study is intended to shed more light on this topic.…”