tailieunhanh - Nonlinear analysis of thermal behavior for a small satellite in Low Earth Orbit using many-node model

In this paper, nonlinear thermal responses of a small satellite in Low Earth Orbit (LEO) are analyzed using many-node model. The main elements of primary structure of the satellite include six rectangular cover plates and a solar array linking with satellite's body. These elements can be modeled as different lumped thermal nodes. | 66 SCIENCE & TECHNOLOGY DEVELOPMENT, Vol 20, 2017 Nonlinear analysis of thermal behavior for a small satellite in Low Earth Orbit using many-node model Pham Ngoc Chung, Nguyen Dong Anh and Nguyen Nhu Hieu Abstract— In this paper, nonlinear thermal responses of a small satellite in Low Earth Orbit (LEO) are analyzed using many-node model. The main elements of primary structure of the satellite include six rectangular cover plates and a solar array linking with satellite's body. These elements can be modeled as different lumped thermal nodes. We use an eight-node model for estimating temperatures at nodal elements . six nodes for cover plates, and two nodes for front and rear surfaces of the solar array. The nodes absorb three major heat energy sources from the space environment consisting of solar irradiation, Earth’s albedo and infrared radiation. The established system of thermal balance equations for nodes is nonlinear and is solved by a numerical algorithm. For simulation purpose, it is assumed that the satellite always remains Earth-pointing attitude during motion. Temperature evolutions of nodes in time are explored in details. The obtained results show that the predictive temperature values of nodes are within the allowable temperature limit range of the satellite. Index Terms—small satellite, Earth- pointing, thermal response, temperature limits. 1 INTRODUCTION T hemal analysis is one of the most important tasks in processes of designing, manufacturing and launching a satellite. It guarantees that all kind Manuscript Received on July 13th, 2016. Manuscript Revised December 06th, 2016. This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number: "". Pham Ngoc Chung, Faculty of Basic Sciences, University of Mining and Geoology, Duc Thang, Bac Tu Liem Dist., Hanoi, Vietnam (e-mail: chunghumg86@). Nguyen Dong Anh, Institute of Mechanics, Vietnam Academy of .