What are the torque characteristics of gas engines?

The torque characteristics of a gas engine are an important aspect of its performance, which largely determines the power output characteristics and scope of application of the engine.

Firstly, the torque output of a gas engine is usually related to its rotational speed. In the low-speed range, torque will increase rapidly with the increase of speed. This is because during the start-up phase, as the engine speed increases, the intake and combustion efficiency of gas gradually improve, allowing the force generated by combustion to more effectively push the piston to do work, thereby increasing torque. When reaching a certain speed, the torque will reach a peak. The magnitude of this peak torque depends on the design parameters of the engine, such as cylinder volume, compression ratio, and the performance of the gas supply system.

Compared with fuel engines, the torque increase process of gas engines is relatively smooth. This is because the combustion speed and method of gas are different from those of fuel. Gas can burn more evenly in the cylinder, reducing detonation during the combustion process. This smooth combustion process ensures that the increase in torque does not experience the more severe fluctuations seen in fuel engines, resulting in a more linear power output.

In the high-speed range, the torque of the gas engine will gradually decrease. This is mainly because as the speed continues to increase, the intake and exhaust processes are limited by time, and the gas cannot fully enter the cylinder. The exhaust gas after combustion cannot be discharged in a timely manner, resulting in a decrease in combustion efficiency and a reduction in torque. However, some advanced gas engines use technologies such as variable valve timing and turbocharging to improve torque output at high speeds. For example, turbocharging technology can increase the intake air volume, ensuring sufficient gas to participate in combustion at high speeds, thereby maintaining a high level of torque.

The torque characteristics of gas engines are also influenced by the composition and quality of the gas. Different types of gas, such as natural gas, biogas, etc., have different energy densities and combustion characteristics. Gas with high energy density can release more energy during combustion, which helps to improve torque output. Moreover, the purity and pressure stability of gas also have an impact on torque. If there are impurities or unstable pressure in the gas, it will cause insufficient combustion, resulting in a decrease in torque and unstable output.

In practical applications, the torque characteristics of gas engines determine their suitability for situations that require stable power output, such as power generation equipment, some industrial equipment that requires high power smoothness, and some urban buses.