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The supply and exhaust system of the experimental rack on the Chinese space station is a complex integrated system. In this paper, a multi-stage simulation, testing, and verification method is designed for a multi-team, multi-location, and multi-stage integrated gas system. This method is designed to solve the problem of missing input parameters between the gas supply system and the exhaust system. Preliminary tests and strategy verifications were carried out through theoretical simulation and semi-physical simulation, and good calculation results were obtained for the single-rack product. The external systems were tested using a simulation system, and a calculation method was designed to obtain relatively accurate parameters. In the early stage, the performance of the product was predicted using the parameter library of Flomaster and semi-physical simulation methods, but the error was large. In the middle and late stages of development, as some products became realistic, multi-stage testing was carried out using a vacuum simulator, simulated flow resistance, and other methods, achieving a performance prediction with an error of 12% before ground testing. The final ground test and on-orbit test showed that the design and calculation method of this paper is effective. The multi-stage design method proposed in this paper was successfully applied to the integrated gas system of the Chinese space station, which can provide a reference for the design of fluid components in long-term system engineering. [ABSTRACT FROM AUTHOR]

A long afterglow material CaAl2O4:Eu2+,Pr3+ emitting blue light has been synthesized by a high-temperature solid-phase method. The effect of a series of preparation conditions on CaAl2O4:Eu2+,Pr3+ was first investigated using a single-factor preference method, and the optimal synthesis conditions were then obtained through orthogonal tests. The target products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), elemental mapping, fluorescence spectroscopy, and afterglow properties. The XRD results indicate the successful synthesis of CaAl2O4:Eu2+,Pr3+ materials, which was further verified by XPS analysis. The afterglow properties of the target products were further improved by doping with Nd3+ under optimum conditions obtained from orthogonal tests. The improvement was analyzed through XRD, fluorescence, afterglow and thermoluminescence analysis. The results indicate that doping with Nd3+ in CaAl2O4:Eu2+,Pr3+ materials significantly enhanced the afterglow properties, including an initial brightness of 2318 mcd m−2 and a duration of 26.5 hours. Thanks to its excellent blue long afterglow luminescence, the material is anticipated to have applications in energy-efficient lighting systems and solar energy systems. [ABSTRACT FROM AUTHOR]

As an important mission of space stations, space science experiment usually requires effective temperature control measures. Scientific experimental express rack (ER) is a general design for space science experiment. In some space scientific experiments, the temperature of local target element or surrounding exceed heat sink temperature range, effective heating and cooling measures are required. Thermoelectric cooler (TEC) has high reliability and low complexity, which is applicable for temperature control in low gravity conditions. In the ER, the entire surrounding is indirectly heated or cooled by the ambient air, local target element surface is heated or cooled by liquid, TEC is thermal competent for ER thermal control attributed to the low complexity and high reliability, which can enlarge the temperature range of air and liquid. In this paper, a modular integrated thermal control system (MITCS) is designed for a specific ER, which has liquid assembly (LA), TEC assembly (TECA), heat exchanger assembly (HXA) and air cycle assembly (ACA) to provide target surface cooling and heating, entire surrounding cooling and heating. The thermal performance of MITCS using TEC are analyzed, providing guides for the design of the scientific experimental ER and other thermal systems.