before bottom dead center

简明释义

下死点前

英英释义

例句

1.To ensure optimal performance, the fuel injection should occur before bottom dead center.

为了确保最佳性能，燃油喷射应在下死点之前进行。

2.In a two-stroke engine, the exhaust port opens before bottom dead center to allow for better scavenging.

在二冲程发动机中，排气口在下死点之前打开，以便更好地清扫。

3.Proper valve timing is crucial for the engine to operate efficiently before bottom dead center.

适当的气门时机对于发动机在下死点之前高效运行至关重要。

4.The engine timing must be adjusted so that the spark plug fires before bottom dead center.

发动机的点火时机必须调整，以便火花塞在下死点之前点火。

5.The piston reaches its maximum speed just before bottom dead center.

活塞在下死点之前达到了其最大速度。

作文

In the world of mechanical engineering and automotive design, understanding the various phases of an engine cycle is crucial for optimizing performance. One critical phase that engineers pay close attention to is the moment just prior to the piston reaching its lowest point in the cylinder, known as before bottom dead center. This term refers to the position of the piston when it is about to start its upward stroke after reaching the lowest point of its travel. Understanding this phase is essential for various reasons, including fuel efficiency, power output, and overall engine longevity.When an internal combustion engine operates, the pistons move up and down within the cylinders in a rhythmic manner. The term before bottom dead center is specifically used to describe the position of the piston just before it reaches its lowest point. At this point, the engine is preparing for the next power stroke, where fuel is ignited, and the resulting explosion pushes the piston back up. If engineers can optimize the timing and mechanics of this phase, they can significantly enhance the engine's performance.One of the primary benefits of understanding the dynamics of before bottom dead center is the ability to improve fuel efficiency. When the engine is designed to ignite the fuel at the optimal moment, just as the piston approaches this position, it allows for a more complete combustion process. This not only maximizes the energy extracted from the fuel but also reduces emissions, contributing to a cleaner environment. Engineers often use advanced simulation tools to model the behavior of the engine components around this critical point, ensuring that every aspect of the engine is tuned to work in harmony.Moreover, the timing of events occurring before bottom dead center can also influence the power output of the engine. For example, if the ignition occurs too late, the combustion may not provide maximum thrust to the piston, leading to a loss of power. Conversely, igniting the fuel too early can cause knocking, which is detrimental to the engine's health. Therefore, precise control over the ignition timing relative to the piston's position before bottom dead center is vital for achieving optimal performance.In addition to performance and efficiency, understanding the implications of before bottom dead center contributes to the longevity of an engine. Engines that operate with poorly timed ignition or inefficient combustion processes tend to wear out faster due to increased heat and stress on the components. By focusing on optimizing the conditions before bottom dead center, engineers can design engines that not only perform better but also have longer lifespans, reducing the need for frequent repairs or replacements.In conclusion, the phrase before bottom dead center encapsulates a crucial moment in the engine cycle that has far-reaching implications for performance, efficiency, and durability. As automotive technology continues to advance, a deeper understanding of this phase will enable engineers to create even more sophisticated and efficient engines. By harnessing the knowledge surrounding before bottom dead center, the automotive industry can move towards a future where vehicles are not only more powerful but also more environmentally friendly and reliable. This understanding is not just a technical necessity; it is a pathway to innovation in engine design and performance optimization.

在机械工程和汽车设计的世界中，理解发动机循环的各个阶段对于优化性能至关重要。工程师们特别关注的一个关键阶段是活塞即将到达气缸最低点的时刻，这被称为底部死点之前。这个术语指的是活塞在开始向上冲程之前的状态，此时它正处于行程的最低点。理解这一阶段至关重要，原因包括燃油效率、功率输出和整体发动机寿命。当内燃机运转时，活塞在气缸内上下移动，形成一种有节奏的运动。术语底部死点之前专门用来描述活塞在达到最低点之前的位置。在这一点上，发动机正准备进行下一个动力冲程，此时燃料被点燃，随之而来的爆炸将活塞推回上方。如果工程师能够优化这一阶段的时机和机械结构，就能够显著提升发动机的性能。理解底部死点之前的动态变化的主要好处之一是能够提高燃油效率。当发动机设计为在活塞接近这一位置时点燃燃料时，可以实现更完整的燃烧过程。这不仅最大限度地提取了燃料中的能量，还减少了排放，有助于保护环境。工程师们通常使用先进的仿真工具来模拟发动机组件在这一关键点周围的行为，确保发动机的每个方面都经过调校，以实现和谐工作。此外，发生在底部死点之前的事件时机也会影响发动机的功率输出。例如，如果点火时间过晚，燃烧可能无法为活塞提供最大推力，从而导致功率损失。相反，过早点燃燃料可能会导致敲击现象，这对发动机健康有害。因此，精确控制点火时机与活塞在底部死点之前的位置之间的关系，对于实现最佳性能至关重要。除了性能和效率，理解底部死点之前的影响还有助于延长发动机的寿命。运转不良的发动机通常由于部件承受的热量和压力增加而磨损加快。通过关注优化底部死点之前的条件，工程师可以设计出不仅性能更佳，而且使用寿命更长的发动机，从而减少频繁维修或更换的需求。总之，短语底部死点之前概括了发动机循环中一个关键时刻，其对性能、效率和耐用性具有深远的影响。随着汽车技术的不断进步，对这一阶段的深入理解将使工程师能够创造出更加复杂和高效的发动机。通过利用关于底部死点之前的知识，汽车行业能够朝着未来迈进，在这个未来中，车辆不仅更强大，而且更加环保和可靠。这种理解不仅是技术上的必要性，更是推动发动机设计和性能优化创新的途径。