The Relationship Between Diesel Engine Parameters

The three most commonly encountered data when understanding engine parameters are power, torque, and speed. You may have seen these terms and parameters in the manual, but you are not very familiar with their meanings. Today, Guangxi Dingbo Electric Power will discuss the relationship between these three factors with everyone. After understanding them, we can analyze the performance of the engine more comprehensively.

Firstly, Dingbo Power will introduce the concepts of these three, Engine Power unit: hp or kW; Engine Speed Unit: rpm； Torque unit: N·m； Power=n x torque x speed. What do power and torque represent? Why are diesel generators with higher engine power and torque more expensive? What is the relationship between power, speed, and torque? Why does a powerful engine depend on its power and torque? These four questions will be discussed and answered one by one below.

Torque is the force exerted by the piston during one cycle of an internal combustion engine to rotate the engine. There are generally two units of torque, the first being Newton meters; The second type is pound feet. In China, we generally use Newton meters (N · m) more frequently. How should Newton meters be understood? For example, if an engine bursts 200 Newton meters, it is equivalent to applying about 20 kilograms of weight on one end of a one meter lever.

RPM is the number of times the engine rotates in one minute, but there is a two-fold relationship between RPM and cycle. Because the widely used four stroke engine completes one power cycle every two revolutions. That is to say, the engine speed is at 8000 revolutions per minute, which is equivalent to only 4000 power cycles.

The physical definition of power is the amount of work done per unit time. Therefore, power is a physical quantity that describes the speed at which work is done. It can be understood as the energy generated by the engine per unit time. The greater the engine power, the faster the work is done, and the more energy is generated in the same amount of time. Normally, the higher the power of the engine, the higher its maximum speed.

The speed of a diesel engine is much lower than that of a gasoline engine, so under the same displacement, the power of a gasoline engine is higher than that of a diesel engine, but the torque of a diesel engine is higher than that of a gasoline engine. The main reason is that the combustion characteristics of fuels are different. Diesel has a slower combustion speed compared to gasoline, and it takes longer to release energy, resulting in a slower work rate and lower power output. Therefore, diesel engines generally adopt designs with small cylinder diameters and long strokes.

There is a proportional relationship between power, speed, and torque, where power=n x torque x speed (n is a constant). It is not difficult to understand why when we usually see the engine power curve, the torque will suddenly decrease when it reaches its peak, while the speed continues to increase the power and will continue to increase.

For example, the Shangchai E-series engine

1. Adopting turbocharging technology to increase intercooling and tap into the maximum power of the engine

2. The power coverage range is 360-460 horsepower, and the maximum torque can reach 2210 Newton meters

3. Maximum torque engine speed 1100-1400 revolutions per minute

4. Maximum power reserve coefficient 0.3

Dingbo Power was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. If you want get more information, please feel free to send email to sales@dieselgeneratortech.com we will pay highly attention on your question.