New Framework for RBDO Applied in a Thrust Chamber

The design of a thrust chamber (TC) of a liquid propellant engine (LPE) presents several challenges from performance to predicting the optimization and reliability of the TC. Thus, multidisciplinary reliability-based design optimization (MMRBDO) of the TC is significant, which was the concentration of this research. Therefore, a new framework is created using a surrogate model and sensitivity analysis (SA) coupling with hybrid reliability analysis [first-order reliability method (FORM) and adaptive sampling (AS)]. The genetic algorithm (GA) has been used for optimization of the TC. According to this method, the input, output, and their levels were defined. Uncertainties in the TC, such as chamber pressure and mixture ratio, are taken into account as random variables in the reliability-based design optimization (RBDO). The specific impulse (SI) and thrust-to-weight ratio (Ftc/mcc) were selected as objective functions. Finally, the proposed framework has been verified using the Monte Carlo simulation (MCS). The accuracy and performance have been evaluated with two different qualified reliability methods. The results show that the framework is a fast and efficient method for the RBDO of complex systems. This approach can be also used for other engineering applications.