Numerical And Experimental Simulations Of Dynamic Thermal Management Of Small Scale Space Station

Thermal management is the conceptual conversion from passive control of temperature to active management of energy and is an important method that improves the integrity of design of space stations. Dynamic thermal management can not only adapt the station to the variational environment but also make full use of the variational properties to improve the running of space stations.The thesis investigates the dynamic variation of thermal environment of space stations, builds the numerical emulational platform of thermal management and simulates the dynamic thermal processes of space stations. The orbital thermal radiation model of small scale space stations is first finished, then the thermal environmental characteristic of small space stations and the variations of equivalent heat sink are obtained numerically. The dynamic numerical models of thermal components in the thermal management system are established based on the principles of abstraction, simplification and equivalence, and the general solution method, including the discretization of one-dimensional convection, is given. Thermal management simulation platform is constructed using object-oriented method. This platform is then used to study the temperature distribution and fluctuation of module's wall, the fluctuations of thermal control system, temperature and humidity in the cabin for the short and long cycles of the thermal environment changes. This thesis suggests a temperature control method for cooling loops, a temperature and humidity control method of the cabin air and simulates their effectiveness.The thesis designs a Hardware-In-the-Loop-Simulation system, including a virtual radiator and a pseudo radiator, as a betterment of the ground experimental system of thermal management so as to make it available for dynamic thermal simulation. Based on the data from the virtual radiator the peusdo radiator successfully follows the heat dissipation of the space station. With this experimental system, the influence of short cycle fluctuation of the space environment on thermal control system is investigated and the method that reducing the experimental simulation time is tried and analyzed. The experimental results are used to validate the numerical emulational platform. Compared with a real space environment simulation this Hardware-In-the-Loop-Simulationradiator system is cheap, can reduce experimental time and is easy to be adjusted.The thesis also investigates one of the important subsystem in the environment control and life support system, the solid amine carbon dioxide remove system. The mathematical and physical dynamic models are given based on the adsorbent theory of porous medium. Its running and parameters affecting its performance are numerically studied and the method that control the water content in the absorbent bed is recommended. The improvement on system configuration to recover heat is discussed and the operation scheme is given. The method is also analyzed that uses thermoelectric heat pump to recover heat with less electrical energy cost.