crank case scavenging

简明释义

曲轴箱扫气

英英释义

例句

1.The design of the crank case scavenging system affects fuel efficiency.

设计的曲轴箱清扫系统会影响燃油效率。

2.Engine tuners often optimize crank case scavenging for better power output.

发动机调校师通常优化曲轴箱清扫以获得更好的功率输出。

3.The efficiency of the engine largely depends on proper crank case scavenging.

发动机的效率在很大程度上取决于适当的曲轴箱清扫。

4.In two-stroke engines, crank case scavenging is crucial for optimal performance.

在两冲程发动机中，曲轴箱清扫对最佳性能至关重要。

5.Improper crank case scavenging can lead to increased emissions.

不当的曲轴箱清扫会导致排放增加。

作文

The process of internal combustion engines is a fascinating subject that combines physics, engineering, and chemistry. One important aspect of these engines is the method used to remove exhaust gases from the cylinder after combustion. This is where the concept of crank case scavenging comes into play. 曲轴箱排气 refers to a technique used in two-stroke engines to ensure that all the exhaust gases are expelled from the crankcase, allowing fresh air-fuel mixture to enter for the next cycle of combustion. In a typical two-stroke engine, the crankcase serves a dual purpose. It acts as a chamber for the fuel-air mixture and also houses the crankshaft. During the compression stroke, the air-fuel mixture is compressed in the crankcase, which then needs to be transferred to the combustion chamber. However, if the exhaust gases are not completely removed from the crankcase, they can mix with the incoming fresh charge, leading to inefficient combustion and increased emissions.This is where crank case scavenging becomes crucial. The scavenging process involves various methods, including the use of ports and valves. In many designs, the engine uses a combination of pressure differentials and momentum to push out the exhaust gases while drawing in the fresh mixture. For instance, when the piston moves down during the power stroke, it creates a low-pressure area in the crankcase, which helps pull the fresh charge in through the intake port while simultaneously pushing the remaining exhaust gases out through the exhaust port. There are several types of scavenging methods, including loop scavenging, cross scavenging, and uniflow scavenging. Each of these methods has its own advantages and disadvantages. Loop scavenging, for example, is commonly used in smaller engines because it provides a good balance between performance and simplicity. On the other hand, uniflow scavenging is often found in larger engines, as it allows for more efficient gas exchange and better overall performance. Understanding crank case scavenging is essential not only for engineers designing new engines but also for mechanics working on existing engines. By ensuring that the scavenging process is optimized, one can significantly improve engine performance, reduce fuel consumption, and lower harmful emissions. As environmental regulations become stricter, the importance of efficient scavenging techniques will only continue to grow.In conclusion, crank case scavenging plays a vital role in the operation of two-stroke engines. It ensures that the combustion process is efficient by removing exhaust gases effectively and allowing fresh air-fuel mixtures to enter the combustion chamber. As technology advances, we can expect to see even more innovative scavenging methods being developed to enhance engine performance while minimizing environmental impact.

内燃机的工作过程是一个结合了物理学、工程学和化学的迷人主题。这个引擎的一个重要方面是用于在燃烧后从气缸中去除废气的方法。这就是曲轴箱排气概念的用武之地。曲轴箱排气指的是一种在二冲程发动机中使用的技术，旨在确保所有废气都被排出曲轴箱，从而允许新鲜的空气-燃料混合物进入下一次燃烧循环。在典型的二冲程发动机中，曲轴箱起着双重作用。它既作为燃料-空气混合物的腔体，又容纳曲轴。在压缩行程期间，空气-燃料混合物在曲轴箱中被压缩，然后需要转移到燃烧室。然而，如果废气没有完全从曲轴箱中排出，它们可能会与进入的新鲜混合物混合，导致燃烧效率低下和排放增加。这就是曲轴箱排气变得至关重要的地方。排气过程涉及多种方法，包括使用端口和阀门。在许多设计中，发动机利用压力差和动量的组合来推动废气排出，同时吸入新鲜混合物。例如，当活塞在动力行程中向下移动时，它在曲轴箱中产生低压区域，这有助于通过进气口拉入新鲜混合物，同时通过排气口推动剩余的废气排出。有几种类型的排气方法，包括环形排气、交叉排气和单流排气。这些方法各有优缺点。例如，环形排气通常用于小型发动机，因为它在性能和简单性之间提供了良好的平衡。另一方面，单流排气通常出现在大型发动机中，因为它允许更高效的气体交换和更好的整体性能。理解曲轴箱排气对于设计新发动机的工程师以及维修现有发动机的机械师来说都是必不可少的。通过确保排气过程的优化，可以显著提高发动机性能，降低燃料消耗，并减少有害排放。随着环境法规变得越来越严格，高效排气技术的重要性只会继续增长。总之，曲轴箱排气在二冲程发动机的运行中发挥着至关重要的作用。它通过有效去除废气并允许新鲜的空气-燃料混合物进入燃烧室，确保燃烧过程的高效。随着技术的进步，我们可以期待看到更多创新的排气方法被开发出来，以增强发动机性能，同时最小化对环境的影响。