Pre Chamber Combustion Chamber of Diesel Generator

At present, a considerable number of high-power diesel engines both domestically and internationally use pre chamber combustion chambers. This is because compared to direct injection combustion chambers, under the same average effective pressure conditions, the maximum combustion pressure of the pre chamber is low, the concentration of harmful components in the combustion products is low, and it is not sensitive to fuel quality. It can effectively reduce mechanical load and combustion noise, as well as reduce exhaust pollution.

The pre combustion chamber of a diesel generator consists of two parts: the pre combustion chamber and the main combustion chamber. The pre combustion chamber is located inside the cylinder head, accounting for 25% to 40% of the compressed volume, and has one or several through-holes connected to the main combustion chamber. Fuel is injected into the precombustion chamber, and after ignition, a portion of the fuel burns. The unburned mixture is high-speed injected into the main combustion chamber and further mixed with air for combustion. This combustion chamber is suitable for small and medium-sized diesel engines.

Structural characteristics

1. The entire combustion chamber is divided into two parts. The pre combustion chamber is located inside the cylinder head and accounts for 25-40% of the total combustion chamber volume. The main combustion chamber is located above the piston. 2. The fuel injector is installed near the centerline of the precombustion chamber, and for the convenience of cold starting, an electric glow plug is often installed. 3. The pre combustion chamber is made of heat-resistant steel separately and installed in the cylinder head without direct contact with the coolant. 4. Most of the fuel is in the main; The schematic diagram of the pre chamber combustion chamber structure in the following figure shows mixed combustion in the combustion chamber, which belongs to the spatial mixing mode.

Characteristics of mixed gas formation

1. Using compressed turbulence for pre ignition. 2. Utilize strong combustion vortices to promote complete combustion. 3. The atomization quality requirements for fuel injection are not high, and a large diameter single hole nozzle that is not easily clogged can be used. The fuel injection pressure is relatively low (8-12MPa), and it has the ability to adapt to large speed ranges and different ignition performance fuels. 4. Smooth operation, low combustion noise, but poor economic performance. The heat loss is significant and the starting performance is poor, requiring the installation of a glow plug device.

From this, it can be seen that during the compression process, the pre chamber type of diesel engine does not generate strong and organized vortices in the pre chamber, only unorganized flocs are generated, forming combustion vortices in the pre chamber, causing fuel to spray and distribute in the main combustion chamber. The passage between the precombustion chamber and the main combustion chamber is relatively small, resulting in high resistance, high energy consumption, and high fuel consumption. However, the pressure difference between the precombustion chamber and the main combustion chamber is large, and the flow velocity of the airflow through the channel is also high, which can form strong combustion vortices. The fuel and air are better mixed, making the fuel burn more completely and the smoke exhaust lighter, with lower fuel requirements. In addition, due to the small size of the pre combustion chamber channel and strong throttling, the combustion in the main combustion chamber is relatively slow and the maximum pressure is also relatively low. Therefore, the work is relatively stable. The pre combustion chamber has a large area, more heat dissipation, smaller channels with the main combustion chamber, and stronger throttling, making starting more difficult and resulting in higher fuel consumption.

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.