Thermal-structural Analysis Of Hoop Deployable Antenna In Space Environment

As an important component of information communication between spacecraft and earth,the performance of antenna directly affects the quality of communication.The complex and variable space thermal environment will change the temperature field of antenna in orbit,which will affect its structural performance and lead to the occurrence of thermal stress and thermal deformation.In this paper,the hoop deployable antenna is used as the object,and the thermal-structural characteristics in space environment are studied as follows.The method of thermal-structural analysis is proposed,and the thermal properties of the space environment are summarized.The characteristics of space low temperature,vacuum,microgravity and three kinds of space heat sources such as solar radiation,earth reflection and earth radiation and their effects on spacecraft are analyzed in detail.The main heat transfer modes in space,heat radiation and heat transfer,are described,and the heat balance relationship of spacecraft in orbit is studied.The structural performance indexes of the hoop deployable antenna affected by temperature are decided,including surface accuracy and tension distribution.Considering the true stress state of cable net surface and the comprehensive influence of space environment,this paper proposes a method for calculating the temperature field of hoop deployable antenna based on the form-finding result.Combined with Stefan-Boltzman thermal radiation and Fourier thermal conduction theory,the thermal radiation-conductivity coupling calculation method for one-dimension rods is analyzed.According to the structural topology and size parameters of hoop deployable antenna,the node coordinates are calculated,the element properties are set and the corresponding model is established by ABAQUS with form finding.Furthermore,the temperature field distribution of the antenna in different time of the geostationary orbit is calculated via UG.The results show that the overall temperature range of the antenna is large in the vernal equinox,and the antenna on the two lateral positions shows the high temperature on one side and the low temperature on the other side.On the front position,the temperature difference between the front and rear cable net surfaces is large.The back position is in the shadow area of the earth,and the overall temperature is low.During the summer solstice,the overall temperature of the antenna is significantly higher than that of the vernal equinox,and the range of variation is narrowed.The temperature of the cable net surface at each position of the orbit is higher,the distribution is more uniform,and the temperature difference between the surrounding trusses is larger.The autumnal equinox and winter solstice are similar to the temperature fields of spring and summer due to the symmetry of the orbit.The thermal deformation theory and the corresponding calculation formula are analyzed.Combined with ABAQUS and MATLAB programming,the influence of temperature fields during vernal equinox and summer solstice on antenna structure is calculated.The results show that the temperature field distribution can change the stress distribution of the antenna.The thermal stress of the summer solstice is higher than that of the vernal equinox.The surface accuracy deteriorates under different temperature fields,especially the straight position of vernal equinox.For the tension distribution,except the increasing tension ratio of the front and rear cable net surfaces in lateral and back positions,the change of other positions is not obvious,and the tension distribution of the longitudinal adjustment cables is relatively uniform.In addition,the influence of the thermal deformation of antenna on the temperature field distribution is studied.It is found that the influence of thermal deformation on the temperature field distribution is very weak.