The optimization goals of cam profile design usually include improving the engine's power, economy, emission performance, working stability and reliability. For extended range engines, these performance improvements are particularly important because they directly affect the engine's endurance and overall performance.
2. Optimization methods
Apply advanced simulation software: Use professional engine simulation software such as GT-VTRAIN and GT-POWER to design and optimize the cam profile. These software can simulate the working process of the engine and draw performance curves to help engineers evaluate the impact of different cam profiles on engine performance.
Consider the working requirements of the engine: Design the cam profile reasonably according to the engine's working speed, power requirements and emission requirements. For example, when the engine's low and medium speed torque is required to be improved, the cam profile can be optimized to improve the intake efficiency, thereby increasing the torque output.
Optimize the geometry of the cam profile: Adjust the lift, acceleration and other parameters of the cam profile to make it smoother and more stable. This helps to reduce the sudden changes in the speed and acceleration of the follower and valve, thereby reducing vibration and noise and improving the stability of the engine.
Consider lubrication and wear: The contact stress and lubrication effect between the cam and the tappet have a direct impact on the wear between the cam and the tappet. Therefore, when optimizing the cam profile, it is necessary to ensure appropriate contact stress and reasonable lubrication effect to alleviate the wear between the cam and the tappet.
Perform dynamic analysis: Establish a dynamic model of the valve train and perform dynamic analysis on the cam profile. This includes evaluating the smoothness of valve movement, lubrication performance, and impact and contact stress between the cam and the follower. Through dynamic analysis, the cam profile can be further optimized to ensure that it meets the working requirements of the engine.
3. Evaluation of optimization effect
Performance improvement: By optimizing the cam profile design, the engine's performance parameters such as torque and power are usually improved. This helps to improve the engine's power and economy.
Emission improvement: The optimized cam profile helps improve the combustion process of the engine, thereby reducing the generation of emissions. This is of great significance for meeting increasingly stringent emission regulations.
Improved stability and reliability: The optimized cam profile makes the valve movement smoother, reducing vibration and noise. At the same time, reasonable lubrication and wear control also help improve the reliability and durability of the engine.
In summary, the extended range engine camshaft can significantly improve the performance of the engine by optimizing the cam profile design. This includes improving power, economy, emission performance, working stability and reliability. In the optimization process, it is necessary to apply advanced simulation software, consider the working requirements of the engine, optimize the geometry of the cam profile, consider lubrication and wear, and perform dynamic analysis. Finally, the effectiveness and feasibility of the optimization design can be verified through the optimization effect evaluation.
