The structural configuration and characteristics of an automobile engine's fuel injection system have a direct impact on the engine's performance. Computational analysis of the fuel system is a crucial method for improving engine performance. Based on the analysis of the structure and mathematical models of the components of the engine's electronic fuel injection system, a simulation model was established, and the structural parameters of the fuel system were optimized through matching calculations. The research results indicate that a plunger diameter and lift of F23x24, along with a injection hole number and diameter of 7xF0.45, provide superior fuel injection characteristics. Additionally, the flow area of the solenoid valve's drain port, as well as the timing and duration of the electrical activation, significantly influence the fuel injection characteristics of the system. The optimized structural parameters hold important reference value for the design of engine fuel systems.
In modern manufacturing and processing production lines, production equipment is an important part of manufacturing production. The full utilization of equipment has a direct impact on the matching of production needs. This article considers the concept of “man-machine factor,” which is the ratio of the number of operators required per piece of equipment to the number of pieces of equipment. A multi-objective optimization function model considering the production line balance rate, smoothing index and human-machine coefficient was constructed. In order to solve this problem, the improved adaptive NSGA- II algorithm is used to solve the model. The research results show that: ① On the premise of meeting the customer's rhythm requirements, adjusting the human-machine coefficient can improve the production line balance rate, reduce the smoothing index and production costs. ② Through numerical examples, it is verified that compared with the traditional NSGA- II algorithm, the improved adaptive NSGA- II algorithm can find an approximate Pareto solution set with higher quality and wider coverage, providing choices for decision makers. This proves the validity and practicality of this research method. This research provides an effective optimization method for modern manufacturing processing production lines and provides a reference for other similar industries.
Compared with traditional fuel vehicle and pure electric vehicle,the noise,vibration,harshness(NVH)problem of range extender electric vehicle is more complicated because of the influence of range extender control strategy.The unreasonable matching control logic is easy to cause problems such as high acceleration noise,roar,etc.,and the later change cost is large and the cycle is long.In this paper,the theoretical model of the range extender system is simplified and the range extender system is regarded as an integral excitation source.By monitoring the state of the whole vehicle,the performance of the vibration and noise of the key points in the vehicle under different effective torque and crankshaft speed output by the range extender system,and avoiding the poor performance of the NVH strategy points,in the early stage of the project,the matching optimization of the vibration and noise of the key points in the vehicle can be realized,save cost and shorten project development cycle.
To quantitatively analyze the influence of solenoid valve parameters on their dynamic response characteristics, mathematic models are built based on the electromagnetic theory. Research is carried out using mathematical models, whereby the dynamic response process of the solenoid valve driven by constant voltage is simulated. The four parameters, namely: driven voltage, initial air gap distance, spring preload, and the number of coil turns influence the dynamic characteristics of the solenoid valve. The solenoid valve displacement curves under different parameters are obtained. Theoretically determined relationships between the dynamic response characteristics and the structural and control parameters of the solenoid valve, provide the basis for the parameter matching of the solenoid valve, and the optimized design of electronic control fuel systems.
汽柴油双燃料燃烧模式可以降低柴油机中小负荷的氮氧化物和碳烟排放并提高有效效率.文章在一台光学发动机上,采用高速摄影的方法对汽柴油均质混合气引燃(HCII)燃烧进行了解析,针对汽油比例对 HCII 燃烧的影响开展了可视化研究.研究结果表明,HCII 燃烧的过程是火焰首先随着柴油喷束从汽缸中央向四周延展,同时点燃周围的汽油混合气产生蓝色火焰,蓝色火焰逐渐发展至整个燃烧室范围.汽油火焰在多点被同时点燃,火焰面积在极短时间内迅速增加,覆盖几乎所有缸内范围,相对于传统汽油机,HCII燃烧速度明显增加.随着汽油比例的增加,缸内蓝色火焰比例明显增加,火焰亮度降低,从而实现低温燃烧.
