Recently, the mid-term meeting for the national key R&D program "Development and Application of Key Technologies of Dedicated Ammonia Internal Combustion Engines for Hybrid Heavy-Duty Commercial Vehicles", led by Yuchai Co., Ltd., was held in Changshu, Jiangsu Province.
The first prototype pure ammonia engine (internal combustion engine running solely on ammonia fuel) developed under this program has completed successful ignition and maintained stable operation, marking a milestone breakthrough for the project.
At the ignition ceremony, leading officials and experts including Wu Zhixin, Chairman of the Electric Vehicle Subcommittee of the National Technical Committee of Auto Standardization; Li Shusheng, Vice Chairman and Secretary-General of the Chinese Society for Internal Combustion Engines; Jia Bin, Secretary-General of the China Internal Combustion Engine Industry Association; Wang Tianyou, Executive Vice President of Tianjin University; Lin He, Executive Vice Dean of Wuxi Carbon Neutral Power Technology Research Institute, Shanghai Jiao Tong University; Zhong Yuwei, Deputy General Manager of Yuchai Co., Ltd.; and Lin Tiejian, Chief Engineer of Yuchai Co., Ltd., jointly witnessed this historic moment.
The successful ignition of the world's first large-displacement high-pressure direct-injection pure ammonia engine dedicated to hybrid power marks a historic breakthrough by Yuchai in zero-carbon power research. The engine realizes coordinated operation with a high-pressure ammonia-to-hydrogen system, and delivers practical implementation and verification of the technology that adopts pre-chamber jet ignition to ignite high-pressure direct-injected liquid ammonia.
Integrated with multiple cutting-edge core technologies including a dome combustion chamber, active pre-chamber, in-cylinder high-pressure direct injection of liquid ammonia, coupled aftertreatment for low-temperature and high-efficiency conversion of multi-nitrogen-based products, and intelligent control for co-injection of multi-hydrogen-based fuels, this internal combustion engine matches the peak thermal efficiency of existing heavy-duty diesel engines. It delivers an all-new zero-carbon power solution for heavy long-haul commercial vehicles that balances superior full-life-cycle cost performance with low-carbon emission reduction requirements, facilitating the green and zero-carbon transformation of conventional internal combustion engines.
In terms of control units, the project has developed a dedicated controller for hybrid ammonia engines, filling Yuchai's gap in independent core control software for hybrid-specific ammonia internal combustion engines. This self-developed controller is equipped with a high-computing multi-core processor and large-capacity storage modules, featuring fully independent and controllable core control logic. It can precisely regulate pre-chamber ignition, ammonia-hydrogen mixture formation and liquid ammonia injection, substantially boosting Yuchai's core competitiveness in the zero-carbon engine sector.
The ammonia-to-hydrogen system deployed for this ignition adopts the technical route of catalytic cracking high-pressure hydrogen production, breaking the technical barriers to efficient catalytic conversion of ammonia for hydrogen generation under low-temperature and high-pressure conditions.
Equipped with a novel low-temperature ruthenium-based catalyst, the system can achieve high-efficiency hydrogen production from ammonia at a low temperature range of 400℃ to 450℃, drastically cutting the hydrogen production energy consumption and high-temperature wear of the equipment.