The central part of the reflector in this scheme is similar to the previous one. The only difference lies in the manner of manufacturing the central mirror. In the latter case it's made with three layers is rigidly connected with the framework central part of energy system. The secondary mirror is installed on three hollow rods. Two of them are used as ducts for a coolant that rejects heat from the secondary mirror. The working medium passes in sequence through the recuperator and spiral-shaped duct situated on the back side of mirror. The chamber of the heat receiver is combined with the thermal storage system and all this is placed in the central part of the energy setup. The specific feature of this system is the additional surface of the channels that receive solar energy straight at the inlet of such a combined receiver. A rotating assembly is made as one unit and consists of a radial outflow compressor and a radial inflow turbine. Analysis The advantages of this system are as follows: • convenient packaging of the heat receiver with high performance; • good packaging of the collector- receiver subsystem as in the previous scheme; • Brayton power system with Kassegrain type collector satisfying better the imposed limit in maximal dimension. The system also possesses the following disadvantages: • secondary mirror reduces the reflecting efficiency of the collector; • necessity to cool the secondary mirror increases the value of pressure drop. As the result of preliminary comparative evaluation, the Kassegrain type collector is preferable. The mirrors with short focal length meet the demand of the size limit. The use of the hollow receiver combined with thermal energy storage decreases heat losses. There is no need to deploy anything for the majority of the subsystems, except for the petal-shaped part of collector. The other units are tightly connected. General mounting and adjustment can be fulfilled at plants on the Earth. Research of Working Process in High Temperature Storage System. The results of the development of latent heat storage systems in aforementioned dynamic space systems are also described here. The heat storage system is combined here with the heat receiver. The maximal temperature in this system will approximately be in range 1150 to 1175 K. Fluoride lithium (LiF) will be used as a phase change medium (PCM). The main feature of this PCM is its transparency. One of the main problems arising while developing such systems is low heat transfer rate in thermal energy storage (TES) due to low heat conductivity of the PCM. Devices, which enhance heat transfer rate, are offered to solve this problem. The purpose of this investigation was better understanding of the working process that goes on during the melting of semitransparent materials at high temperature. Experiments were performed with a cylindrical heat storage enclosure. The cross section of this enclosure is shown in Figure 5.
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