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为了设计出世界上最大功率的1000r/min柴油机,广泛应用了工程预测工具。设计功率为10MW的RK280型柴油机在零部件的热负荷和机械负荷两方面均达到了新的技术水平。其安全性、可靠性、排放、整机尺寸/重量目标以及输出功率和燃油消耗率指标的实现,均离不开可靠的工程预测工具的广泛应用。MANB&W柴油机公司经过市场调查,并吸取了RK270型柴油机10多年的经验,确定了RK280型柴油机总的设计目标。其后再经过周密严谨的概念分析程序,其中包括公司内的性能预测程序、计算流体力学分析以及有限元分析,很快就确立了诸如缸径和行程、V形夹角、转速和功率范围等主要参数。在RK270型柴油机上取得的紧凑的排气管系统经验帮助设计师们设计出从气缸出口到高效涡轮增压器的高效排气传递系统。高喷射压力和短喷射持续期的燃油喷射系统是其早期分析过程的另一特点。随着过程的进一步扩展,进行了单个部件和系统的更为详细的热力学、结构和动力学的分析。在进行详细设计的同时,对关键部件进行超负荷条件下的加速疲劳试验,这使得关键部件的结构在开发过程的较早时期就固定下来。燃烧过程的3维模拟对设计进行了验证,并进一步减少了在权衡燃油经济性和排放性能方面所需付出的工作量。发动机开发和制造工程师在设计中广泛应用工程预测方法以保证所完成的设计能以最有效的优化方式进行制造和组装以及使用和维修。本文将介绍在预测发动机热力学、气体动力学特性过程中所采用的方法和程序,并介绍在获取发动机可靠的安全系数和发动机的完善性的过程中所采用的有限元方法。
In order to design the world’s largest power 1000r / min diesel engine, widely used engineering prediction tools. The design of RK280 diesel engine with a capacity of 10 MW has reached a new technological level in both thermal and mechanical loading of components. Its safety, reliability, emissions, unit size / weight target, and output power and fuel burn rate targets are all inseparable from the widespread use of reliable engineering forecasting tools. MANB & W Diesel Engine Company after market research, and learned from RK270 diesel engine 10 years of experience, identified the RK280 diesel engine design goals. Subsequent rigorous and rigorous conceptual analysis procedures, including in-house performance prediction programs, computational fluid dynamics analysis and finite element analysis, soon established such as bore and stroke, V-shaped angle, speed and power range and other major parameter. The compact exhaust system experience gained on the RK270 diesel engine helps designers design efficient exhaust delivery systems that run from the cylinder outlet to a highly efficient turbocharger. Fuel injection systems with high injection pressure and short injection duration are another feature of their earlier analysis. As the process further expanded, more detailed thermodynamic, structural, and kinetic analyzes of individual components and systems were conducted. At the same time as detailed design, accelerated fatigue testing of the critical components under overload conditions allowed the structure of the key components to be fixed earlier in the development process. The 3-D simulations of the combustion process validate the design and further reduce the amount of work required to balance fuel economy and emissions performance. Engine development and manufacturing engineers use engineering prediction methods extensively in their designs to ensure that the finished design can be manufactured and assembled as well as used and maintained in the most efficient and optimized way possible. This article describes the methods and procedures used in predicting engine thermodynamic and aerodynamic characteristics and introduces the finite element method used to obtain reliable engine safety and engine integrity.