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In this investigation, an innovative modification process has been employed to enhance the capability of a novel multi-generation energy system (MGS) utilizing a dual-flash binary geothermal cycle incorporated with two main subsystems. These subsystems include a novel cooling, heat, and power (CCHP) unit by an ejector-based cooling cycle (ERC) joint to an organic Rankine power cycle (ORC) and a hydrogen generation setup via a low-temperature electrolyzer. In addition, a binary mixture consisting of Pentane and R142b has been utilized for the CCHP subsystem as a working fluid. Nonetheless, to assess the actual operating cost of investigated system, the exergetic and energy level-based exergoeconomic (modified exergoeconomic) analysis has been implemented instead of using conventional exergoeconomic analysis; afterward, due to the conflicting trend between design and performance parameters, dual parametric sensitivity study and double-objective optimization using NSGA-II approach have been carried out. According to the outcomes of dual parametric study, the results are further sensitive to the simultaneous variation in second flash tank inlet pressure and vapor generator temperature. Optimization results indicate that the net electricity production has increased from 33.04 kW to 40.59 kW, which improves the exergetic efficiency of the system by 4.39 %. Also, in this case, the total unit product cost has ameliorated by 3.4% and 2.62% in terms of modified and conventional cost approaches. The best representative optimal solution has the optimal energetic efficiency, exergetic efficiency, and unit product cost of 38.35%, 43.50%, and 52.52 $/GJ, respectively.

Among the various thrust vector control methods, this study investigates the utilization of mechanical deviation of the nozzle by incorporating a flow deflector path in the flow emanating from the nozzle outlet, which is applied in the aviation industry. The researchers conducted simulations to assess the deviation of the thrust vector using exit vanes within the nozzle. Two parameters, namely the thrust force ratio and the axial force ratio, were calculated to regulate the thrust vector. The results demonstrated that employing vanes successfully deviated the thrust vector, reducing force coefficients. Notably, vanes with lower angles proved more suitable for thrust vector deviation. Optimization and prediction were conducted to forecast the performance of the vanes based on their angle and nozzle pressure ratio (NPR). The prediction outcomes exhibited favorable agreement with the simulation results, confirming the accuracy of the prediction method. This research provides valuable insights into the thrust vector control mechanism employing mechanical deviation of the nozzle and underscores the significance of predicting vane performance for optimal thrust vector selection.

A ventricular pump is a device used to treat patients with heart failure. In this device, the blood pressure is very important. On the other hand, the power use and efficiency are very important due to the battery volume reduction. In this study, it was attempted to introduce an optimum example of this pump using computational fluid dynamics (CFD) as an accurate method along with kriging and surrogate meta-models to reduce time and particle swarm optimization (PSO) algorithm. 5 indicators have been investigated as geometric optimization indicators in this study. Blade inlet angle, blade outlet angle, number of blades, the distance from the leading edge of the blade to the inlet eye of the pump and finally the width of the blade (viewed from the side to the blade) are the geometrical indicators analyzed in this study for their effects on the optimization. In this study, the power, efficiency, head, hemolysis and relative hemolysis have been analyzed, and hemolysis and efficiency have been introduced as the main objectives of PSO and pump head has been considered as a constraint. The introduced optimum example has reduced hemolysis more than 9% and power use more than 10% compared to the model investigated by the American Food and Drug Administration, while the efficiency has also increased by more than 2% and the related constraint to the pump head is maintained.