【作者】 李明；

【导师】 周少祥；

【作者基本信息】 华北电力大学(北京) ， 动力工程（专业学位）， 2016， 硕士

【摘要】 CMTS(Cable Modem Terminal Systems)设备是国家大力发展三网融合的产品,三网融合即电信网、广电网和互联网信号的融合。DOCSIS系统是其网络传输的终端设备,由CMTS和CM电缆调制解调器组成。CMTS的散热功耗上百瓦,需要在最高65℃的环境下工作并要求有超长寿命,所以CMTS的散热设计尤为重要。本文使用UG8.5进行产品设计的前期模拟计算和结构优化,优化设计一款可以满足CMTS产品散热要求的压铸外壳。本文主要通过收集CMTS每个元器件的尺寸和功耗信息,确定CMTS元器件的温度使用规格等。建立UG8.5的立体模型,使用其Advanced Simulation模块,设定材料、功耗、网格、边界和环境等信息进行CMTS散热仿真模拟计算。由于铝合金ADC12价格便宜、重量轻、导热系数较高、压铸工艺成熟等因素,所以设备金属外壳采用ADC12。本文主要通过UG软件模拟优化铝合金外壳壁厚,内部CMTS模块化散热结构设计,整体CMTS尺寸和散热片形状来提高CMTS散热性能。并综合考虑不同的CMTS摆放方式对散热的影响等。模拟过程中采用局部增加导热垫,合理布局热源和减少CMTS设备界面热阻等来提高CMTS设备的散热能力。最终选择散热性能最优化的结构方案来加工一套设备,进行试验,与CMTS的仿真结果进行对比及分析。设备使用环境广泛,从-40℃到65℃。只有良好的散热才能保证CMTS长时间稳定工作。本论文的研究是通过优化室外CMTS设备散热能力,来满足CMTS设备越来越小并且散热功能越来越强的趋势,同时最大程度的降低CMTS设备的散热成本,提高其市场竞争力。更多还原

【Abstract】 CMTS(Cable Modem Terminal Systems) devices are the product of our country strongly develop in integration of three networks, which are integrated by telecommunication network, Cable TV network and Internet. DOCSIS system is the terminal equipment of network transmission, consists of CMTS and cable modems.Power consumption of CMTS is about one hunbred watt, it need to work at up to 65 degrees Celsius environment and require a long life, so it is particularly important in thermal design. This paper is using UG8.5 to simulate, calculate and optimize CMTS structure of preliminary product design, build die casting product to meet thermal requirement.In this paper, first to collect the size, power consumption information and thermal specifications of every CMTS components, and confirm limit using environment. Then build 3D model by UG 8.5, the Advanced Simulation module is for specialized thermal simulation in UG, by setting material, power consumption, grid, boundary, environmental information and so on to do simulation calculation. Advantages of aluminum alloy ADC 12 are cheap, light wight, high thermal conductivity, mature die casting technology and so on, so our CMTS housing is ADC 12. Mainly study method of this paper is software simulation, by optimizing wall thickness of housing, the internal thermal module structure, the overall structure size and fin shape to improve equipment heat dissipation performance. And considering the impact to heat dissipation of the different installation directions. Housing internal considerings are to add thermal pad in specific place, reasonable layout of heat source, and reduce equipment interface thermal resistance to improve the heat dissipation capability. Finally choose the better project to process a set of equipment to do thermal test. Comparing real test results with thermal simulation.Equipment will be used from -40 degrees Celsius to 65 degrees Celsius. Only the good thermal design can ensure CMTS working stably for a long time. Research of this paper could improve CMTS heat dissipation ability, and adapt to the development of science and technology, at the same time we try to reduce the cost, improve its market competitiveness.更多还原