Optimization Design And Study Of A Solar-boosted Kalina Thermal Energy Conversion System

With the depletion of fossil energy and the strong demand for ecological and environmental protection,the exploitation of marine thermal energy has gradually become a hot spot for new energy development.The ocean temperature difference can have unique advantages of large thermal energy reserves and stable heat source quality.However,because the temperature difference between cold and hot seawater is relatively small,major equipment losses in the cycle are large,resulting in low efficiency of the entire ocean temperature difference power generation system.This paper focuses on these two factors that mainly affect the efficiency of heat utilization.Based on previous research,the research on optimizing the entire power generation system will provide a theoretical basis for commercialization.The main research contents of this article are summarized as follows:(1)Solar thermal energy is used as an auxiliary heat source to design a solar thermal power system for the operation of the ocean temperature difference power generation system,and an ORC test bench is used to perform the principle verification and feasibility analysis;(2)In order to achieve better thermal energy utilization efficiency,based on the previous research on thermal energy utilization,Kalina cycle was selected as the thermal utilization scheme of ocean thermoelectric power generation system.At the same time,for the cyclic state characteristics of a solar-assisted ocean thermoelectric power generation system,a process optimization plan using an ejector was proposed.The results showed that the optimized cycle efficiency was improved by 9%.The commercial Aspen Plus software was used for simulation to further analyze the influence of various parameters in the cycle on the system performance,and the optimum operating conditions were obtained after the optimization of the cycle operation,which provided a theoretical basis for the operation of the solar-assisted Kalina thermoelectric power generation system;(3)For the structural characteristics of the heat exchanger in the power generation system,the groove flow path of its internal structure was experimentally studied.Through the experiments of additional pulsating flow on groove channels of different geometries,the flow characteristics of the fluctuating laminar flow basins with different parameters are analyzed.The main focus is on the fluctuating flow fields with different parameters.Pressure drop situation.It has been found that the groove channel with smaller groove length shows a smaller pressure drop in the pulsating flow laminar basin,and the pressure drop decreases with the pulsating flow velocity;(4)In order to further investigate the effect of additional pulsating flow in the groove access on the overall heat transfer,a numerical simulation study was carried out on this part,focusing on the influence of the pulsating flow with different parameters on the heat transfer and the different geometry The mechanism of influence in the groove channel.The research shows that the low-frequency pulsating flow can improve the heat transfer in the groove channel,and is affected by the protruding structure of the groove.The groove with smaller groove length has the best heat transfer results.