Not long ago, China’s well-known equipment manufacturing enterprises released the world’s first thermal efficiency for Weichai Group. The commercial diesel engine breaking through 50% has caused a great sensation in the domestic and foreign counterparts. This breakthrough marks that China’s heavy-duty diesel engine technology has achieved independent control of key core technologies.


Thermal efficiency and emissions are often a contradiction. On the premise of meeting the national 6 emission standards and regulations, improving thermal efficiency is actually a comprehensive improvement of the comprehensive technology of internal combustion engines. Su Wanhua, the academician of the Chinese Academy of Engineering, said that it is very difficult to improve thermal efficiency. The diesel engine has been developed since 1897. The thermal efficiency has increased from 26% to 46%, but with the increasingly stringent emission standards, it is more and more difficult to improve the thermal efficiency. The 50% thermal efficiency is regarded as a problem in the field of internal combustion engines. In recent years, Daimler Benz, Volvo Cummins, and other international giants are making every effort to tackle key problems. But they have only been able to reach 50% in the laboratory with waste heat recovery. How to commercialize a diesel engine with a thermal efficiency of 50%. It is a worldwide problem.


How did the Weichai Group do it?

In 2015, the Group launched a 50% thermal efficiency commercial diesel engine project. And set up a special technical research team to create a coordinated combustion technology, coordinated design low friction loss, low emission pollutant intelligent control, and other problems. technology, exhaust energy distribution technology, zoning lubrication technology. Intelligent control technology, five specialized technologies. It has solved the problem of high-efficiency combustion, low heat transfer, high explosion pressure, and high reliability.

When the project started, few people believed that it would succeed. Li Zhijie was the vice president of Weichai Power Engine Research. He is also one of the core personnel of the 50% thermal efficiency diesel engine project team. A diesel engine with a thermal efficiency of more than 50% is a lifelong dream of every internal combustion engine engineer. I was lucky enough to be involved in this project, and I had to do my best.

Breaking through 50% is not an overnight achievement in a certain link, but a readjustment and optimization of almost all engine systems such as friction heat dissipation and combustion. After the repeated design, feasibility analysis, and simulation tests. At the end of 2017, the optimization plan gradually became clear, and Li Zhijie’s team gradually had a bottom in mind.

However, there are still many variables for the virtual solution in the computer to fall on food. Continuous R & D and investment are needed in the later stage. Faced with difficulties, Tan Xuguang, chairman of Weichai Group, said. A 50% thermal efficiency diesel engine project is the core business of the group. The input is not capped and the manpower support is not limited.

In addition to the core team Weichai Engine Research Institute, more than 1000 people participated in the project and invested 4.2 billion yuan.

At the current industry level of 46%, it is estimated that carbon dioxide emissions can be reduced by 8% when the thermal efficiency is increased to 50% of diesel consumption. Weichai 50% thermal efficiency diesel engine project manager Wang Baojun said.