bottom dead point

简明释义

下死点下止点

英英释义

例句

1.The crankshaft rotates 180 degrees to reach the bottom dead point 下止点.

曲轴旋转180度以达到下止点。

2.The engine's pistons reach the bottom dead point 下止点 before changing direction.

发动机的活塞在改变方向之前到达下止点。

3.To measure the cylinder volume accurately, you need to find the bottom dead point 下止点.

要准确测量气缸容积，需要找到下止点。

4.During the compression stroke, the piston moves from the bottom dead point 下止点 to the top.

在压缩行程中，活塞从下止点移动到顶部。

5.When tuning the engine, it's crucial to check the timing at the bottom dead point 下止点.

在调校发动机时，检查在下止点的时机至关重要。

作文

The concept of the bottom dead point is crucial in understanding the mechanics of engines, particularly in internal combustion engines. To grasp this term fully, we must first delve into the basic operation of an engine. An internal combustion engine works by converting fuel into energy through a series of controlled explosions. These explosions push a piston down a cylinder, and as the piston moves, it creates power that ultimately drives the vehicle. However, there are specific points in the piston's movement that are essential for the engine's efficiency and performance. One of these critical points is referred to as the bottom dead point (BDP). The bottom dead point is defined as the position of the piston when it is at its lowest point in the cylinder. At this stage, the piston has completed its downward stroke and is about to begin its upward movement. Understanding this point is vital for several reasons. Firstly, the bottom dead point is significant in the timing of fuel injection and ignition. For optimal performance, the engine's control system must precisely time when to inject fuel and ignite it. If the timing is off, the engine may experience knocking, reduced power, or even failure to start. This is because the fuel must ignite at the right moment to create the maximum force on the piston as it begins its upward stroke from the bottom dead point. Secondly, the bottom dead point plays a role in the overall efficiency of the engine. When the piston reaches this point, it creates a vacuum in the cylinder that helps draw in more air and fuel for the next cycle. This is crucial for maintaining the engine’s power output and ensuring that it runs smoothly. If the engine does not efficiently draw in the necessary mixture of air and fuel, it can lead to incomplete combustion, which results in wasted fuel and increased emissions. Moreover, the bottom dead point is also important for understanding the wear and tear on engine components. When the piston reaches this point, it experiences significant forces acting upon it. Over time, these forces can lead to wear on the piston rings and cylinder walls. Understanding the stresses at the bottom dead point helps engineers design better materials and components that can withstand these forces, ultimately leading to longer-lasting engines. In conclusion, the bottom dead point is not just a technical term but a fundamental aspect of engine operation that affects performance, efficiency, and durability. By comprehending the significance of the bottom dead point, we can appreciate the intricate engineering that goes into creating reliable and powerful internal combustion engines. As technology continues to advance, understanding such concepts will remain essential for both engineers and automotive enthusiasts alike.

“底死点”这一概念对于理解发动机的机械原理至关重要，尤其是在内燃机中。要充分掌握这个术语，我们首先要深入了解发动机的基本运作。内燃机通过一系列受控爆炸将燃料转化为能量。这些爆炸推动活塞在气缸中向下移动，随着活塞的运动，产生的动力最终驱动车辆。然而，活塞运动中有几个特定的点对发动机的效率和性能至关重要。其中一个关键点被称为“底死点”（BDP）。底死点被定义为活塞在气缸中处于最低点的位置。在这个阶段，活塞完成了向下的行程，即将开始向上的运动。理解这个点至关重要，原因有很多。首先，底死点在燃油喷射和点火的时机上具有重要意义。为了实现最佳性能，发动机的控制系统必须精确地计算何时喷射燃油和点燃。如果时机不对，发动机可能会出现敲击、功率下降，甚至无法启动。这是因为燃油必须在正确的时刻点燃，以便在活塞从底死点开始向上行程时产生最大力量。其次，底死点在发动机整体效率中也发挥着作用。当活塞到达这个点时，它在气缸内产生真空，有助于吸入更多的空气和燃料以进行下一循环。这对维持发动机的功率输出并确保其平稳运行至关重要。如果发动机未能有效吸入所需的空气和燃料混合物，可能导致燃烧不完全，从而浪费燃料并增加排放。此外，底死点对于理解发动机部件的磨损和撕裂也很重要。当活塞到达这个点时，承受着显著的力量。随着时间的推移，这些力量可能导致活塞环和气缸壁的磨损。理解底死点处的应力有助于工程师设计出能够承受这些力量的更好材料和部件，最终使发动机更加耐用。总之，底死点不仅仅是一个技术术语，而是发动机运作的基本方面，影响着性能、效率和耐久性。通过理解底死点的重要性，我们可以欣赏到创造可靠且强大的内燃机所需的复杂工程技术。随着技术的不断进步，理解这样的概念将继续对工程师和汽车爱好者至关重要。