scavenging pressure

简明释义

清除压力

英英释义

例句

1.Engine tuners often adjust the scavenging pressure 排气压力 to enhance power output.

发动机调校师常常调整排气压力以增强功率输出。

2.In two-stroke engines, maintaining adequate scavenging pressure 排气压力 is crucial for efficiency.

在二冲程发动机中，保持足够的排气压力对效率至关重要。

3.A higher scavenging pressure 排气压力 can lead to better fuel atomization and combustion.

更高的排气压力可以导致更好的燃油雾化和燃烧。

4.The design of the exhaust system directly affects the scavenging pressure 排气压力 in high-performance vehicles.

排气系统的设计直接影响高性能车辆的排气压力。

5.The engine's performance improved significantly when the scavenging pressure 排气压力 was optimized.

当发动机的排气压力被优化时，性能显著提升。

作文

The concept of scavenging pressure is crucial in the field of thermodynamics and fluid mechanics, particularly when discussing internal combustion engines. In simple terms, scavenging pressure refers to the pressure difference that drives the exhaust gases out of the cylinder and allows fresh air-fuel mixture to enter. This process is essential for the efficient operation of an engine, as it directly affects the power output and overall performance. Without adequate scavenging pressure, the engine may suffer from incomplete combustion, leading to reduced efficiency and increased emissions.To understand how scavenging pressure works, we must first look at the four-stroke engine cycle. During the intake stroke, the piston moves down, creating a vacuum that draws in the air-fuel mixture. As the piston moves back up during the compression stroke, the mixture is compressed before being ignited. After combustion, the piston moves down again, pushing the exhaust gases out during the power stroke. The final stage, the exhaust stroke, is where scavenging pressure plays its vital role. Ideally, the design of the exhaust system should create a low-pressure zone that helps pull the exhaust gases out of the cylinder.Several factors influence scavenging pressure. One of the most significant is the design of the exhaust manifold and the length of the exhaust pipes. A well-designed exhaust system can enhance the scavenging pressure by utilizing the momentum of the exiting exhaust gases to create a suction effect that draws out more gases from the cylinder. This phenomenon is often referred to as 'tuned exhaust,' where the dimensions of the exhaust system are optimized to resonate at certain engine speeds, effectively increasing the scavenging pressure at those RPMs.Another factor that affects scavenging pressure is the timing of the intake and exhaust valves. If the valves are not timed correctly, it can lead to overlap, where the exhaust valve is still open when the intake valve begins to open. This can cause a loss of scavenging pressure and result in a phenomenon called 'reversion,' where exhaust gases flow back into the intake manifold, contaminating the fresh air-fuel mixture.In addition to mechanical design, the type of fuel used can also impact scavenging pressure. Fuels with different combustion characteristics will produce varying amounts of exhaust gas, which can affect the pressure dynamics within the cylinder. For instance, higher octane fuels may burn more completely, resulting in less residual exhaust gas and potentially improving scavenging pressure.In conclusion, understanding scavenging pressure is essential for anyone involved in engine design or performance tuning. It plays a pivotal role in ensuring that an engine runs efficiently and produces maximum power while minimizing emissions. Engineers must consider various factors, including exhaust system design, valve timing, and fuel type, to optimize scavenging pressure for better engine performance. As technology advances, the methods for enhancing scavenging pressure continue to evolve, leading to more efficient and powerful engines that meet the demands of modern transportation and environmental standards.

在热力学和流体力学领域，尤其是在讨论内燃机时，scavenging pressure的概念至关重要。简单来说，scavenging pressure指的是驱动排气气体排出气缸并允许新鲜空气-燃料混合物进入的压力差。这一过程对于发动机的高效运作是必不可少的，因为它直接影响功率输出和整体性能。如果没有足够的scavenging pressure，发动机可能会出现燃烧不完全的情况，从而导致效率降低和排放增加。要理解scavenging pressure的工作原理，我们必须首先了解四冲程发动机循环。在进气冲程中，活塞向下移动，产生真空，吸入空气-燃料混合物。当活塞在压缩冲程中向上移动时，混合物被压缩，然后点燃。燃烧后，活塞再次向下移动，在动力冲程中将废气推出。最后一个阶段，即排气冲程，是scavenging pressure发挥重要作用的地方。理想情况下，排气系统的设计应创造一个低压区，帮助将废气从气缸中抽出。影响scavenging pressure的因素有很多。其中最显著的是排气歧管的设计和排气管的长度。设计良好的排气系统可以通过利用排出废气的动量来增强scavenging pressure，从而产生一种吸力效应，将更多的气体抽出气缸。这种现象通常被称为“调谐排气”，其中特定转速下排气系统的尺寸经过优化，以有效提高该转速下的scavenging pressure。另一个影响scavenging pressure的因素是进气阀和排气阀的时机。如果阀门的时机不正确，可能会导致重叠，即当进气阀开始开启时，排气阀仍然打开。这可能导致scavenging pressure的损失，并导致所谓的“回流”现象，即废气流回进气歧管，污染新鲜的空气-燃料混合物。除了机械设计外，使用的燃料类型也会影响scavenging pressure。不同燃烧特性的燃料将产生不同数量的废气，这会影响气缸内的压力动态。例如，辛烷值较高的燃料可能燃烧得更完全，从而产生较少的残余废气，可能改善scavenging pressure。总之，理解scavenging pressure对于任何参与发动机设计或性能调校的人来说都是必不可少的。它在确保发动机高效运行、最大限度地提高功率和减少排放方面起着关键作用。工程师必须考虑多种因素，包括排气系统设计、阀门时机和燃料类型，以优化scavenging pressure以提高发动机性能。随着技术的进步，增强scavenging pressure的方法不断演变，导致更高效、更强大的发动机，满足现代交通和环境标准的需求。