The Chinese engine developer releases the world’s first commercialized diesel engine with a brake thermal efficiency above 50 percent.
Weichai Group, a leader in China’s internal combustion engine industry, has officially launched the first commercialized diesel engine in the world to have a brake thermal efficiency above 50 percent.
During a launch ceremony Sept. 16, 2020, both TÜV SÜD, a world authoritative testing organization; and the China Automotive Technology and Research Center Co., Ltd. – the country’s national internal combustion engine testing organization – awarded Weichai certificates for brake thermal efficiency of 50.26 percent. The engine was jointly unveiled by Ling Wen, vice governor of Shandong Province and academician of the Chinese Academy of Engineering; and Tan Xuguang, chairman of Shandong Heavy Industry Group and Weichai Group.
An internal combustion engine’s brake thermal efficiency is a measure of its fuel efficiency. Engines with higher brake thermal efficiency rates have lower fuel consumption, higher energy savings, and reduced emissions.
Since the development of the first diesel engine in 1897, the engine’s brake thermal efficiency of the diesel engine increased from 26 to 46 percent, where it remained until now. Although brake thermal efficiency evolved over the past 100-plus years, global development statistics and increasingly stringent emission regulations made improvement more difficult in recent years.
To solve this technical problem, Weichai drew on its more than 70 years of experience in the internal combustion engine industry as well as its technical expertise in manufacturing, researching, and developing diesel technology. For the past 10 years, the company invested 30 billion yuan in R&D, which includes recruiting more than 200 doctors, more than 300 global high-end talents, and more than 3,000 graduate students to its staff.
Weichai’s R&D and production base in Weifang, China, has annual manufacturing and sales of more than 1 million units. The center has achieved technological breakthroughs in commercial vehicle powertrains, CVT powertrains and hydraulic powertrains, complementing China’s core technical shortcomings in these areas and promoting the country’s diesel engine industry chain to continue to move forward.
Since 2015, Weichai’s special technical research team has conducted a large number of simulations and bench tests to improve the efficiency of its engines, eventually leading to this historic breakthrough. Weichai credits the high brake thermal efficiency rate to five proprietary technologies: advanced fields synergy combustion technology, harmonious design technology, exhaust energy distribution technology, subzone lubrication technology, and WISE control technology. Together, these technologies help achieve high-efficiency combustion with low heat transfer, high PFP with high reliability, low friction loss, low emission pollutants, intelligent control, etc., attaining a brake thermal efficiency exceeding 50 percent.
Weichai’s advanced fields synergy combustion technology optimizes the design of the air passage, fuel injection, combustion chamber profile and other systems to make the relationship between the velocity field and concentration field in the combustion chamber more harmonious, increasing combustion speed by 30 percent.
Harmonious design technology enables the diesel engine body’s to withstand high PFP, which greatly limits combustion improvement, by about 60 percent. The technology also strengthens the engine’s overall structure.
The company’s exhaust energy distribution technology, developed in response to the increased difficulty of emission control caused by improved combustion, pioneered reconstruction of the exhaust system design. The technology adapts to the demand for exhaust gas recirculation while ensuring the efficiency of turbines, meeting regulations and standards, and achieving a 1 percent increase in brake thermal efficiency.
Subzone lubrication technology, developed based on the different characteristics of the friction pairs of the system, uses several friction reduction technologies to reduce the overall friction by 20 percent. WISE control technology takes advantage of Weichai’s self-developed ECU by creatively developing a series of more precise control predictive models, making every part of the diesel engine more efficient.
Weichai’s achievement is a historical moment in the development of internal combustion engines. Several domestic and international institutions and experts including Bosch Group, AVL List GmbH, FEV, SAE, China Machinery Industry Federation, China Internal Combustion Engine Industry Association, and China-SAE congratulated Weichai on this breakthrough and praised the company for setting a new benchmark for the brake thermal efficiency of global diesel engines and making new contributions to the energy-saving and emission reduction capabilities of internal combustion engines.
Weichai not only launched the world’s first base diesel engine with a brake thermal efficiency of over 50 percent, but also easily met China VI/Euro VI emission requirements. The engine is the first of its kind ready for mass production and commercialization. According to industry experts, increasing brake thermal efficiency from 46 to 50 percent reduces diesel consumption by 8 percent and carbon dioxide emissions by 8 percent. If all 7 million heavy-duty diesel engines now in use in China were replaced with diesel engines with 50 percent brake thermal efficiency, 33.32 million tons of fuel and reduce carbon dioxide emissions by 104.95 million tons can be saved annually – a significant contribution to solving energy shortages and global warming problems.
The launch of the engine solidifies China’s position as a world leader in heavy-duty diesel engine technology. Weichai has received strong support from Bosch Group and other global suppliers and R&D consulting institutions in the development of this program. Weichai’s future plans include partnering with more global companies to move toward a goal of 55 percent thermal efficiency, Chairman Tan Xuguang announced during the Sept. 16 ceremony.