541 / 2019-01-14 21:20:46

低速柴油机二级增压系统设计/Design of two-stage supercharging system for low speed diesel engine

低速机；二级增压；改善燃烧；压比分配/Low speed diesel engine ; Two-stage supercharging; Improved combustion; Pressure ratio distribution

全体主题 > 先进能源系统

摘要：低速柴油机以其本身功率大转速低等特点，已经成为绝大多数的大型远洋船舶的动力源。随着时代发展，对低速柴油机的要求也逐渐增多，如今可持续发展和环保意识的加强，使得节能减排的力度越来越大，而如何改善低速柴油机的燃烧和油耗始终是工程师们需要面对的一个难题。为了节约航运成本，大多数的低速柴油机都会燃烧重油，这使得低速柴油机的燃烧恶劣，耗油量高。二级增压相对于普通的单级增压可以为柴油机提供更高的增压压力，为燃烧提供更充足的氧气，所以将二级增压系统运用到低速柴油机上可以有效的改善燃烧，降低油耗。本文利用GT-Power软件建立低速柴油机仿真模型，并进行标定，通过数学理论进行总增压压力的估算，匹配合适的二级增压系统以及压比的分配，最后将二级增压系统与单级增压进行对比。从对比的结果可以看出二级增压的响应速度快，特别是在低工况时，在全工况范围内柴油机性能都有所提高。

Abstract: Low-speed diesel engines have become the power source for most large-scale ocean-going vessels due to their high power and low speed. With the development of the times, the requirements for low-speed diesel engines are gradually increasing. Nowadays, the development of sustainable development and environmental awareness has made energy conservation and emission reduction more and more important. How to improve the combustion and fuel consumption of low-speed diesel engines is always required by engineers. In order to save shipping costs, most low-speed diesel engines burn heavy oil, which makes the low-speed diesel engine burn poorly and consumes a lot of fuel. Compared with the ordinary single-stage supercharging, the two-stage supercharging can provide higher supercharging pressure for the diesel engine and provide more oxygen for combustion. Therefore, applying the secondary supercharging system to the low-speed diesel engine can effectively improve the combustion and reduce the fuel consumption. In this paper, GT-Power software is used to build a low-speed diesel engine simulation model, and calibration is carried out. The total supercharging pressure is estimated by mathematical theory, matching the appropriate two-stage supercharging system and pressure ratio distribution, and finally the two-stage supercharging system and single Level boost is used for comparison. From the comparison results, it can be seen that the response speed of the two-stage supercharging is fast, especially in the low working condition, the performance of the diesel engine is improved in the whole working condition range.