Wu Xiuxia

After the outburst of the financial crises, the diesel engine market demand declined with the continuous slide of the shipbuilding market. Anqing Zhong Chuan Diesel Engine Co Ltd made a decision to take diesel engine as the main body to realize breakthrough development of “one body and two wings”. In the aspects of diesel engine and gas engine, Anqing Diesel Engine gave full play to 57-year diesel engine production, R&D experience and talent base to develop dual fuel and gas engine. ACD320 gas engine/dual fuel engine are just domestic eco-friendly models dedicated to by Anqing Diesel Engine. The models applied latest design idea, low carbon, environmentfriendly, efficient, complete machine index reached domestic leading and international first class level, filled domestic gap and Anqing Diesel Engine established itself as the domestic independent R&D pacemaker of big power medium-speed natural gas engine.

High Performance and Eco-Friendly Engine

At present, main technical bottlenecks of domestic marine dual fuel engine development lie in two aspects:One is automatic shift of fuel oil and gas model; the other is micro ignition fuel injection≤1% (main fuel oil). Only by breakthrough of the two technologies,can intelligent shift of fuel oil and gas of dual fuel engine be realized and can NOx emissions meet IMO Tier III requirements.

At the design idea stage of ACD320 gas engine/dual fuel engine project, Anqing Diesel Engine R&D team members performed complete market survey and massive data consulting, through repeated research and comprehensive comparison, they finally determined selected ACD320 dual fuel engine should apply highend main micro-injection dual injector technology. With scheme available,they selected micro ignition system production supplier, they aim at high end, through survey and argumentation of domestic and overseas micro ignition system manufacturers, they finally selected a Swiss renowned company as micro ignition system supplier and took part in the joint design. In order to solve the technical problem, the Anqing Diesel Engine R&D team proceeded with fuel combustion characteristics,built process control model of oil and gas shift, optimized control algorithm to balance and control fuel oil and fuel gas injection, thus realizing steady shift between oil and gas. In the micro ignition system development aspect,the team applied computational fluid dynamics software to simulate the position of fire core and travel path of in-cylinder flame, optimized cylinder cover design, solved dual oil atomizer layout problem, ensured gas ignition in 1% micro ignition injection condition and met IMO Tier Ⅲ relevant emission requirements. In December 2013, the project was officially kicked off and it only took one year to complete concept design, 3D detailed design and 2D detailed design.

At the project test stage, they developed a detailed working plan,gradually advanced in line with the node plan, and in order to break through the key technology of dual model efficient combustion, the project team members applied a lot of simulated test technologies with solid theoretical foundation and practical experience accumulated in early-stage gas engine R&D. Irrespective of day and night,the R&D team surmounted various difficulties, and with mutual support and concerted effort, the testing assignment advanced in full swing in line with the node requirements. Benefiting from breakthrough of key technologies, Anqing Diesel Engine improved thermal efficiency of ACD320 gas engine to above 45%. In future, Anqing Diesel Engine will set out for marketization and serial development of the gas engine and continuously develop more efficient and energy-saving new models.

Independent Innovative Protracted Campaign

There is no fixed model to follow in new product development. The ACD320 gas engine/dual fuel engine project developed by Anqing Diesel Engine is a key project approved by the Ministry of Industry and Information Technology.The model is the domestic first gas engine applied in the shipbuilding sector, composed of two models of natural gas and dual fuel, marked by advantages of small volume, big power, high efficiency, easy operation and modularization, able to meet the requirements of IMO Tier Ⅲ emission standard, complete engine design index reaches domestic first class and international leading level.

To complete the ACD320 gas engine prototype development task, Anqing Diesel Engine integrated domestic and overseas resources, borrowed advanced technology, performed industry,university and research combination,conducted in-depth study of big power gas engine key technology. The Company R&D team conducted massive theoretical study and test verification in combustion mechanism, ignition property, combustion characteristics and micro jet control,captured R&D technical difficulties in efficient combustion system, intelligent control system, micro ignition system and special parts. From R&D and design to completing bench test, Anqing Diesel Engine ACD320 gas engine R&D team took three years to achieve the goal.The development of ACD320 dual fuel gas engine broke through the key technology restricting China big power gas engine R&D, improved engine R&D capability, and what is more important,created the national brand of dual fuel engine, and the ship “China heart”is expected to provide robust power for development of the Chinese shipbuilding industry.

At present, China has entered the strategic period of energy structure adjustment and new energy development,it is accelerating the development of strategic emerging energy industries,racing to control commanding heights for a new round of global energy science and technology competition.In future, low carbon, environmentfriendly and efficient ACD320 series gas engines entering the market and large scale application will speed up China shipping energy structure adjustment,energetically promote green development of the shipbuilding industry and play an important role in meeting dual challenges of energy security and environmental protection.

Moreover, while capturing R&D technical difficulties in ACD320 gas engine/dual fuel engine, Anqing Diesel Engine coordinated resource allocation issues, ensured the prototype quality and pursued quality culture;improved productivity to ensure the implementation of “ABC+” activities;by appraising and electing “Innovation Expert” and “ Breakthrough Project” award on a quarterly basis,improvement potential in the company was constantly triggered, the longterm mechanism of improvement and development was formed, product transformation and upgrading was promoted to new step, the enterprise was driven to form a new model of good circular development.★