| With the development of society,the problem of energy shortage and pollution caused by traditional energy is becoming more and more serious.The disc-solar power system has the advantages of high power efficiency and independent power generation,but its thermoelectric conversion device is large in size and heavy in mass,which is not conductive to the distributed application of the system.A new type of rotary thermoelectric converter is analyzed and designed in this paper.Under the condition of ensuring the power generation efficiency,the complexity and weight of the thermoelectric conversion device are reduced,and the weight and cost of the traditional dish solar power generation system are greatly reduced by combining with the parabolic concentrator formed by the gentle cable network structure,so as to promote the wide application of the solar thermal power generation system.This paper mainly includes the following contents:Firstly,theoretical analysis and performance calculation of rotary thermoelectric converter are carried out.Based on the Rankine cycle,the working process of the device is analyzed in detail,including working medium selection,working medium state analysis,energy relationship and energy loss in the cycle process,etc.In the case of selecting two different working media,the influence of temperature and pressure of working medium on system performance is analyzed through programming calculation,so as to set reasonable state parameters.Other operating parameters of the system are calculated,including working medium state parameters,thermal cycle efficiency and power of the whole system,etc.,and system performance is compared and summarized under the two working conditions.Secondly,the structure design and optimization of the collector in the thermoelectric conversion device are carried out.Taking the flat plate collector structure as the prototype and combining with the conceptual design scheme of the device,the structure design of the collector part is carried out in more detail.Based on the engineering heat transfer,the energy balance model of the collector is established through the theoretical analysis of the heat loss of each part of the collector.The results show that the structure design of the collector is reasonable.Compared with the first working condition,the second working condition requires lower strength and better economy.Taking lightweight as the goal,the optimized design was carried out for the collector.After the optimization,the mass of the device was only 0.21 kg,down by 33%.Finally,the pneumatic design and performance analysis of the expander in the thermoelectric converter are carried out.The centripetal turbine was used as the expander,and the initial design parameters were selected by screening method.On the one hand,the main aerodynamic and structural parameters of the centripetal turbine are obtained through onedimensional aerodynamic analysis.On the other hand,the initial design parameters are input into the turbine design software to complete the aerodynamic design.The parameter error of the two design methods is within 10%,indicating that the design parameters are reasonable.Based on the one-dimensional aerodynamic analysis,the three-dimensional modeling design was completed and the numerical simulation was carried out.The results showed that although some regions had a small range of shock waves,the overall distribution was relatively uniform,which basically met the design requirements.The internal efficiency of the expander under variable working conditions is analyzed and substituted into the system to calculate the thermal efficiency.The results show that increasing the total heat absorption of the system can effectively improve the internal efficiency of the expander and to some extent the thermal efficiency of the system.The work of this paper is to explore and refine the new type of rotary thermoelectric conversion device,which has certain reference value for the design of small saucer solar power system thermoelectric conversion device. |
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