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701.
为满足提高电力网容量、电压等级和综合自动化水平的需求,对具有220kV侧有8回出线、110kV侧有10回出线的变电所进行电气设计。通过对3种方案的技术分析和比较,选择双母线接线技术,同时确定主变压器容量、主变压器台数、主变压器型式和结构,最终选择变电所变压器的型号。 相似文献
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Y. Bai L. Y. Fan X. Z. Ma H. L. Peng E. Z. Song 《International Journal of Automotive Technology》2016,17(4):567-579
In this paper, the bond graph model of common rail injector was proposed in consideration of the effects of variable liquid capacitance and fuel physical property on the injection characteristics of the injector. State equations were derived based on the model, which were numerically solved by programming in Matlab. Comparisons between the simulation results and the experimental data show that the numerical model can effectively predict the injection quantity of the system. Effect of variation of delivery chamber diameter, needle seat semi-angle, needle cone semi-angle, ball valve seat semi-angle, nozzle hole diameter, inlet orifice diameter and outlet orifice diameter on fuel injection quantity had been analyzed. The influence rules of various parameters on the fuel injection quantity had been established. The experiments were conducted using face centered central composite design. A second order polynomial response surface model had been developed for predicting fuel injection quantity, as a function of the independent variables. Analysis of variation was used to determine the significance interactions which primarily affect the fuel injection quantity. It had been concluded that six interaction factors including delivery chamber diameter with nozzle hole diameter, needle seat semi-angle with needle cone semi-angle, needle seat semi-angle with nozzle hole diameter, needle cone semi-angle with nozzle hole diameter, nozzle hole diameter with inlet orifice diameter, and nozzle hole diameter with outlet orifice diameter have significant effect on the fuel injection quantity of the system. 相似文献
704.
地埋式污水厂较传统污水厂除臭系统及通风系统的能力要求更高。本文研究了除臭通风系统风量计算方法,结合除臭系统设计、通风系统设计及仿真模拟,避免在设计和运行时造成浪费。提出高效的、精准化的通风收集系统设计思路,以某地埋式污水厂污泥脱水间为例,采用计算流体力学(CFD)模型进行模拟优化。提出运行控制对策,同时满足除臭通风效果安全、设备安全、节能降耗,提高能源利用效率。 相似文献
705.
液力缓速器对车辆制动时,车辆动能损失将由工作介质吸收,然后通过热交换器传递给整车散热系统。缓速器上的温度传感器实时反映缓速器热交换器出水口温度及工作腔油温,根据温度自动控制扭矩可防止温度过高对产品使用及整车运行产生影响。本文首先介绍了温度传感器在液力缓速器的重要性,然后对温度传感器的工作要求及使用环境进行了分析,最后进行了产品设计与试验验证。 相似文献
706.
More and more high voltage direct current (HVDC) converters are being located in a load area in the Yangtze River Delta Region in China. It's large transmission capacity and intensive placement are hardly seen in other countries. Accurate and reliable study tools and methods are extremely needed for power system engineers and researchers to deal with such problems which were never met before and otherwhere. A novel approach on electromagnetic modeling of alternating current / direct current (AC/DC) system is proposed and simulation is carried out to replay a real AC 3-phase to ground fault on a multi-infeed high voltage direct current (MIHVDC) system. AC system is specially simplified. Dynamic models and real parameters are adopted in main AC/DC equipments concerned and retained. Modeling and simulation are based on the power system computer aided design/electro-magnetic transient in direct current (PSCAD/EMTDC) system software package. Comparisons between simulation results and the records from the fault recorders are studied including both AC and DC quantities. 相似文献
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在弹塑性理论的基础上,考虑了材料性能随温度的变化,应用J2流动理论导出了高温下钢筋混凝土构件弹塑性增量本构模型,编制了该模型的有限元求解程序.该模型具有明确的物理意义,表达形式规范,便于数值手段实现.数值计算结果与现有的试验模型基本吻合. 相似文献