A Study Of Heat Transfer And Vibration In Solar Array

Solar panels of spacecraft in outer space is heated by the radiation of the sun and the other stars. The thermal deformation and thermal vibration of the structure of the panels induced by the temperature field have an important impact to the security and reliability. The drifting space junk may collides with the solar panels. The dynamics characteristic of the structure is an important indicator when spacecraft was designed. Thornton theoretical basis of the theory of thermal analysis using finite element software Marc in this paper. First, the main beam of solar panels on the Hubble Space Telescope is simulated when it was heating in solar radiation and cooling in the Earth's shadow. It has the temperature field of the main beam while the paper simulated the thermal deformation and thermal stress of the main beam. The result in this paper is in good agreement with the numerical solutions and theoretical calculation. Modal analysis of the cantilever main beam is studied by Marc software when the elastic modulus changed with temperature. The dynamic response of the cantilever end is studied when it beated a point load. Finally, the cycle temperature field of the solar panels is simulated and so the dynamic response with temperature changing, focusing on the dynamic response of the solar panels when they were collided by the space junk.Through this research, the main results obtained in this paper are as follows:(1) During heating, the main beam' temperature of the solar panels began to stabilize about 15 minutes of sunshine, steady-state maximum temperature of 158.4℃, the minimum temperature is 116.6℃, the average temperature is about 130℃. During the cooling, around the main beam' temperature difference of 150 seconds is less than 0.1℃. The temperature of the main beam section is quite similar with the outside ambient temperature about 1000 seconds.(2) When the main beam of the solar panels shined by the sunshine, the temperature distribution of the cross-section is the sinusoidal distribution. Beginning within 15 minutes of sunshine, the overall temperature is rising. After 15 minutes, the outward radiation heat of the main beam is equal to the heat absorption. The temperature of the whole main beam reached steady state.(3) When the density and elastic modulus of the main beam decreases with increasing temperature, the natural frequency also reduces accordingly. When the density and elastic modulus did not change with temperature, it was limited that the natural frequency was effect by the temperature change on the main beam.(4) Simulation of the whole solar panels shows that the natural frequency of the whole solar panels is very low and it is a typical flexible structure. Under a temperature cycle, the dynamic response of the main beam is actually due to thermal deformation caused by temperature difference. The velocity and acceleration of the dynamic response are very small.(5) The dynamic response of the whole solar panels was simulated when it was collided by the pulse load, such as space junk. The displacement, velocity and acceleration of the variation with time is given. The maximum stress variation with time and the area of the windsurfing were given too. Then the windsurfing is significantly torsional.