valve timing

简明释义

阀定时

英英释义

例句

1.Adjusting the valve timing can lead to better fuel efficiency in vehicles.

调整气门正时可以提高车辆的燃油效率。

2.The performance of an engine can greatly improve with optimized valve timing.

通过优化气门正时，发动机的性能可以大大提高。

3.Engine tuners often focus on valve timing to maximize horsepower.

发动机调校师通常关注气门正时以最大化马力。

4.Many high-performance cars use adjustable valve timing systems.

许多高性能汽车使用可调节的气门正时系统。

5.The new model features advanced technology for precise valve timing control.

新型号采用先进技术实现精确的气门正时控制。

作文

In the world of automotive engineering, one of the most critical aspects that determine the performance and efficiency of an engine is its valve timing. This term refers to the precise timing of when the intake and exhaust valves open and close during the engine's cycle. Properly adjusted valve timing can significantly enhance an engine's power output and fuel efficiency, while improper timing can lead to a range of issues, including poor performance and increased emissions.To understand the importance of valve timing, we must first look at the four-stroke engine cycle, which consists of intake, compression, power, and exhaust strokes. During the intake stroke, the intake valve opens to allow the air-fuel mixture to enter the combustion chamber. The timing of this event is crucial; if the valve opens too late or closes too early, the engine may not draw in enough air and fuel, resulting in a loss of power.Similarly, during the exhaust stroke, the exhaust valve must open at the right moment to allow the burnt gases to escape efficiently. If the exhaust valve closes too late, it can lead to back pressure, which hampers the engine's ability to draw in fresh air for the next cycle. Therefore, the synchronization of these valves is vital for optimal engine performance.Modern engines often utilize advanced technologies such as Variable Valve Timing (VVT) systems to dynamically adjust valve timing based on engine speed and load conditions. VVT systems allow for improved torque and power across a wider range of engine speeds, enhancing drivability and fuel economy. For instance, in low-speed conditions, the system may alter the valve timing to maximize torque, while at high speeds, it can optimize power output.The benefits of precise valve timing extend beyond mere performance. Engines with well-tuned valve timing systems tend to produce fewer emissions, as they can achieve a more complete combustion of the air-fuel mixture. This is increasingly important in today's automotive landscape, where stringent emission regulations are in place to combat environmental pollution.Moreover, understanding valve timing is not only beneficial for engineers but also for car enthusiasts and mechanics. Knowledge of how valve timing affects engine performance allows for better maintenance and tuning practices. For example, when modifying an engine for increased horsepower, adjusting the valve timing can be one of the most effective ways to achieve desired performance gains without compromising reliability.In conclusion, valve timing is a fundamental concept in engine design and performance. Its significance cannot be overstated, as it directly impacts power output, fuel efficiency, and emissions. As automotive technology continues to evolve, the importance of mastering valve timing will remain a cornerstone of efficient engine operation. For anyone involved in the automotive field, a deep understanding of valve timing is essential for optimizing engine performance and ensuring compliance with environmental standards.

阀门时机是汽车工程中决定发动机性能和效率的关键因素之一。这个术语指的是在发动机周期中，进气阀和排气阀打开和关闭的精确时机。正确调整的阀门时机可以显著提高发动机的功率输出和燃油效率，而不当的时机则可能导致一系列问题，包括性能下降和排放增加。要理解阀门时机的重要性，我们首先需要了解四冲程发动机循环，包括进气、压缩、动力和排气冲程。在进气冲程中，进气阀打开以允许空气-燃料混合物进入燃烧室。这个事件的时机至关重要；如果阀门打开得太晚或关闭得太早，发动机可能无法吸入足够的空气和燃料，从而导致功率损失。同样，在排气冲程中，排气阀必须在正确的时刻打开，以便让燃烧后的气体高效排出。如果排气阀关闭得太晚，可能会导致背压，从而妨碍发动机为下一个循环吸入新鲜空气。因此，这些阀门的同步对于优化发动机性能至关重要。现代发动机通常采用先进的技术，如可变阀门时机（VVT）系统，根据发动机转速和负载条件动态调整阀门时机。VVT系统允许在更宽的发动机转速范围内改善扭矩和功率，从而提高可驾驶性和燃油经济性。例如，在低速条件下，该系统可能会改变阀门时机以最大化扭矩，而在高速时则可以优化功率输出。精确的阀门时机的好处不仅限于性能。调校良好的阀门时机系统的发动机往往能产生更少的排放，因为它们能够更完全地燃烧空气-燃料混合物。在当今汽车行业中，这一点尤为重要，因为严格的排放法规正在实施，以应对环境污染。此外，了解阀门时机对工程师、汽车爱好者和机械师都是有益的。掌握阀门时机如何影响发动机性能，可以更好地进行维护和调校。例如，在对发动机进行增马力改装时，调整阀门时机可能是实现所需性能提升而不妨碍可靠性的最有效方法之一。总之，阀门时机是发动机设计和性能中的基本概念。其重要性不容小觑，因为它直接影响功率输出、燃油效率和排放。随着汽车技术的不断发展，掌握阀门时机的重要性将始终是高效发动机运作的基石。对于任何参与汽车领域的人来说，深入理解阀门时机对于优化发动机性能和确保符合环境标准至关重要。