Multi-Objective Optimal Control of Water-Saturated Fuel Based on Improved NSGA-II-FLC
To solve the problem of heat exchanger wall icing due to excessive temperature difference between fuel and heat transfer oil in the preparation of water-saturated fuel for fuel icing airworthiness tests,a multi-objective optimization method was proposed to improve the dynamic optimization of Non-dominated Sorting Genetic Algorithm-II(NSGA-II)optimal individual input fuzzy logic control-ler to achieve accurate temperature control of the water-saturated fuel.Based on the thermal hydraulicand two-phase pipe flow model,a water-saturated fuel temperature control system with intermediate medium heat transfer oil was built,and the reliability of the simulation model was verified with the test temperature control system,and the system under different temperature conditions was simulated and analyzed.The system temperature settling time defined in the control algorithm was optimized,and the fitness value of temperature differ-ence control was used as the decision objective,the Good Point Set method was introduced to initialize the population,and the Cauchy Mutation(CM)method with variable inertia weight was used to optimize the iterative process.The global optimal control parameters obtained from the improved NSGA-II optimization were fed into the fuzzy logic controller,and the Slope of the parameters in the controller were self-tuned to realize the dynamic optimization of the temperature control model.The results show that the improved NSGA-II-FLC multi-objective optimal control can shorten the temperature settling time,improve the temperature control accuracy by about 50%,and make the temperature difference close to but not exceeding 13℃,which meets the airworthiness requirements.
improved non-dominated sorting genetic algorithm-IIfuzzy logic controllerwater-saturated fuelmulti-objective optimizationintermediate medium heat transfer oil