lower dead center

简明释义

下止点

英英释义

例句

1.The mechanic explained that the piston must not go past lower dead center during operation.

机械师解释说，活塞在运行过程中不能超过下止点。

2.During the compression stroke, the piston moves towards lower dead center.

在压缩行程中，活塞向下止点移动。

3.The engine reaches its maximum torque just before the piston reaches lower dead center.

在活塞达到下止点之前，发动机达到最大扭矩。

4.Identifying lower dead center helps in setting the correct valve timing.

识别下止点有助于设置正确的阀门时机。

5.When tuning the engine, it's crucial to adjust the timing at lower dead center.

在调校发动机时，调整在下止点的点火时机至关重要。

作文

In the world of engineering and mechanics, understanding the principles of motion is crucial for designing efficient machines. One of the key concepts in this field is the term lower dead center, which refers to a specific position in a reciprocating engine or mechanism. To grasp the significance of lower dead center, we must first understand its role in the operation of engines, particularly in internal combustion engines. The lower dead center is the point at which the piston is at its lowest position within the cylinder. This position is critical because it marks the end of the power stroke and the beginning of the exhaust stroke in a four-stroke engine cycle. When the piston reaches the lower dead center, the combustion chamber has just completed its function of converting fuel into energy, and the exhaust valves begin to open, allowing the spent gases to exit the cylinder.Understanding the dynamics of the lower dead center helps engineers optimize engine performance. For instance, if the timing of the valve openings and closings is not synchronized properly with the movement of the piston, it can lead to inefficient combustion, reduced power output, and increased emissions. Therefore, precise calculations and adjustments are necessary to ensure that the engine operates smoothly and efficiently.Moreover, the concept of lower dead center extends beyond just internal combustion engines. It also applies to various mechanical systems, such as hydraulic cylinders and pneumatic actuators. In these systems, the lower dead center represents a position where the force exerted by the fluid is at its maximum, making it an essential factor in the design and operation of hydraulic machinery.In practical applications, understanding the lower dead center can significantly impact the performance and longevity of machines. For instance, in automotive engineering, knowing the optimal timing for gear shifts in relation to the lower dead center can enhance acceleration and overall driving experience. Additionally, in manufacturing processes that involve automated machinery, recognizing the lower dead center can lead to improved cycle times and productivity.In conclusion, the term lower dead center is not just a technical jargon; it embodies a fundamental principle that underpins the functionality of many mechanical systems. By mastering the concept of lower dead center, engineers and technicians can develop better designs, improve efficiency, and ultimately contribute to advancements in technology. As we continue to innovate and create more complex machinery, a solid understanding of such principles will remain essential for success in the field of engineering.

在工程和机械领域，理解运动原理对于设计高效机器至关重要。这个领域的一个关键概念是术语下死点，它指的是往复发动机或机制中的一个特定位置。要掌握下死点的重要性，我们首先必须了解它在发动机操作中的作用，特别是在内燃机中。

下死点是活塞在气缸内处于最低位置的点。这个位置至关重要，因为它标志着动力冲程的结束和四冲程发动机循环中排气冲程的开始。当活塞达到下死点时，燃烧室刚刚完成将燃料转化为能量的功能，排气阀开始打开，允许废气从气缸中排出。

理解下死点的动态有助于工程师优化发动机性能。例如，如果阀门的开启和关闭时机与活塞的运动不同步，可能会导致燃烧效率低下、功率输出减少和排放增加。因此，需要进行精确的计算和调整，以确保发动机平稳高效地运行。

此外，下死点的概念不仅仅适用于内燃机。它还适用于各种机械系统，如液压缸和气动执行器。在这些系统中，下死点代表流体施加的力达到最大的位置，使其成为液压机械设计和操作中的一个重要因素。

在实际应用中，理解下死点可以显著影响机器的性能和使用寿命。例如，在汽车工程中，了解换挡的最佳时机与下死点的关系可以增强加速性能和整体驾驶体验。此外，在涉及自动化机械的制造过程中，识别下死点可以提高周期时间和生产效率。

总之，术语下死点不仅仅是技术术语；它体现了支撑许多机械系统功能的基本原理。通过掌握下死点的概念，工程师和技术人员可以开发更好的设计，提高效率，并最终为技术进步做出贡献。随着我们继续创新并创造更复杂的机械，牢固掌握这样的原理将始终是工程领域成功的关键。