What Is The Turbulent Diffusion Combustion Process Of Gas Fuel Jet
What Is The Turbulent Diffusion Combustion Process Of Gas Fuel Jet
Turbulence causes violent disturbance in the airflow, so its diffusion rate is greatly increased, which can obtain much higher intensity than laminar diffusion combustion. Therefore, the most widely used diffusion combustion in the industry is turbulent diffusion combustion.
Whether the gas and air flowing out of the coaxial casing can conduct turbulent combustion depends on their speed and the speed difference between them. The mixing of the coaxial jet is also closely related to the velocity difference between the central airflow and the peripheral airflow.
Turbulent combustion of gaseous fuels can be achieved by increasing the gas flow rate or taking artificial strengthening measures. Turbulent diffusion combustion can be divided into free turbulent diffusion combustion and forced turbulent diffusion combustion according to different methods of causing turbulence. The former is based on the free jet, while the latter is realized by means of a cross jet and rotary jet.
The flow state of ejecting one medium from the nozzle to another static medium is called a free jet. When the gas flows freely from the small nozzle to the still air, the process and characteristics of the flame transition from laminar diffusion combustion to turbulent diffusion combustion can be observed while the velocity changes from low to high.
If combustible gas (fuel) and air are delivered separately, but the speed of air delivery is very small, it can be considered that combustible gas is delivered into a space full of still air. In this way, the flow state of the gas flow will be determined by the flow rate uo of the combustible gas from the injector. If the air velocity is large enough to make the airflow turbulent, the turbulence will become a free submerged jet. After the jet flows from the outlet of the burner, it absorbs air from the surrounding space in the process of turbulent diffusion. In this way, the quality of the airflow increases, the width of the jet expands, and the airflow velocity decreases and becomes uniform. At the same time, various mixtures of different concentrations are formed under the width of the jet.