April 20, 2022

Inside the cylinder of the diesel engine is the reciprocating motion of the piston to provide power to the car. Displacement is the volume swept by the piston (from top dead center to bottom dead center) during this process, that is, the effective volume. The cylinder volume refers to the total volume of the cylinder, which is equal to the sum of the working volume of the cylinder and the volume of the combustion chamber.

The meaning of diesel engine displacement or cylinder working volume is as follows:

1. Combustion chamber volume: When the piston is at the top dead center, the space formed above the top surface of the piston and below the bottom surface of the cylinder head is the combustion chamber, and its volume is called the combustion chamber volume, and the combustion chamber shed (also called the compression volume. Generally Represented by the letters Vee.

2. The working volume of the cylinder: the piston moves from the top dead center; the volume swept by the bottom dead center is called the working volume of the cylinder. Generally expressed by the letter Vh: Vh=(π/4)D2S0 In the formula, π is the pi (3.14); D is the diameter of the cylinder in mm; S is the stroke of the piston in mm, (the radius of the crank fly).

Diesel engine cylinder volume

3. The total volume of the cylinder: when the piston is at the bottom dead center, the volume between its top and the cylinder head is called the total volume of the cylinder, generally expressed by va. Obviously, the total cylinder volume is the sum of the cylinder working volume and the combustion chamber volume.

4. Displacement: the sum of the working volumes of each cylinder of a multi-cylinder diesel engine is called the displacement of the diesel engine. Generally expressed in VL: VL=Vhi. In the formula, vh is the working volume of the cylinder; i is the number of cylinders. The larger the displacement, the greater the power of the diesel engine.