Showing 3 results for Layout Design
Mahdi Fakoor, Marziye Taghinnezhad, Amir Reza Kosari,
Volume 15, Issue 1 (3-2015)
Abstract
This research deals with configuration design and layout optimization of communication satellite. First, an approach is proposed to design the configuration of GEO satellite. Since propulsion subsystem in GEO satellite is the massive item, it has a significant impact on satellite configuration. Consequently, it is necessary to consider the propulsion subsystem influence on satellite configuration. Then layout design process of the satellite components which is one of the complex problems in engineering is performed. In this paper, in order to optimize the layout design of satellite components, the algorithm which consists of two stages, primary and detail layout, is proposed. In order to express geometric constraints mathematically, the Finite Circle Method (FCM) is used. For The mathematical expression of performance constraints, the distance constrains related to distance relationships between components have been developed. The hybrid optimization method is proposed to optimize layout design which is a combination of Simulated Annealing optimization and Quasi Newton methods. The optimization method validation is applied on simple test problem. Finally, the proposed algorithm for configuration and optimal layout design is implemented on communication satellite. The results show that product of inertial (objective function) are minimized and considered constrains of communication satellite are satisfied.
Hamideh Delaram, Ali Dastfan, Mahmood Norouzi,
Volume 15, Issue 2 (4-2015)
Abstract
In this paper, 3-D simulation of heat transfer in a power electronic device and its cooling system is performed. The device is a high voltage three-phase inverter manufactured by Semikron Company which its main application is in electric and hybrid vehicles. Cooling system is a forced-air plate-fin heat sink. Limitation factor of designing heat transfer is maximum temperature of the inverter’s chips, heat sources, called IGBT. Maximum temperature of IGBTs should be below 125 ᵒC in order to avoidance of both the thermal and the mechanical failures. One of the primary objectives is the reduction of the maximum temperature by designing layout of chips. Also, the heatsink geometry design is accomplished with the consideration of the maximum temperature and tradeoff between both the usage material volume and the heatsink efficiency. Geometries are the number of fins, the fin height, the fin thickness and the base thickness of the heatsink. The power dissipation is estimated using datasheet information and output waveforms obtained from simulation in MATLAB. A thermal model of the inverter and its cooling system are simulated by using finite-element method (FEM). The accuracy of the thermal model and power dissipation estimation are verified by Semisel software. The maximum temperature is significantly reduced about 20 ᵒC by designing layout precisely. Also, the heatsink efficiency is increased 10.35%, 16.67% and 27.51% with the increase of the material volume about 22.52%, 13.51% and 0% for the heat transfer coefficient, 50, 75 and 100 (W/m2.K) by good design of the heatsink geometry ,respectively.
I. Veisi Khanghahi, M. Fakoor, M. Shahryari,
Volume 19, Issue 8 (8-2019)
Abstract
In this paper, in order to minimize the required power of satellite thermal control subsystem, considering known geometric model and the orbital parameters and conditions, the optimal layout design of the satellite subsystems will be performed based on thermal and attitude control constraints. Since all of the satellite subsystems can act only in a certain temperature range, here, by considering the thermal dissipations of each subsystem and incoming thermal loads to each satellite faces in different orbital conditions, by optimally layout of components and sub-systems of the satellite, we will arrive to appropriate configuration plan. The constraints of the thermal subsystem should be satisfied by considering the temperature distribution within the satellite as far as possible. Finally, given that the main purpose of this layout is to provide thermal power, in addition to satisfication of the power budget system constraint, the power of the thermal control subsystem has been reduced by 66%. The superiority of this method is that by following the resulting layout, we obtain a model that needs a thermal control subsystem with less complexity and limited power. Consequently, in addition to decreasing the mass of the satellite, reliability will also be increased. Considering the importance of satellite stability, the layout algorithm and optimization are defined in such a way that the attitude control requirements are observed with the thermal requirements in this layout.
