Why swirl is important to the ignition and combustion of the fuel air mixture?

As the swirl increases, it changes the fuel jet direction to use more air as well as reduces the impingement of fuel jet to the cylinder wall because of penetration reduction [16]. …

What causes turbulence in a combustion chamber?

Turbulence is caused by modified piston. Turbulence enhances mixing and probably produces a leaning effect. The turbulence in the combustion chamber makes the charge into homogeneous and increases the combustibility of fuel. So brake thermal efficiency of modified piston is 2\% more than the normal piston.

What is swirl in engine?

Swirl is usually defined as organized rotation of the charge about the cylinder axis. Swirl can be created by bringing the intake flow into the cylinder with an initial angular momentum [2]. It is well known that the in-cylinder air motion strongly affects the combustion process and consequently their performance.

What is the difference between swirl and turbulence?

Swirl is a turbulent motion of air fuel mixture, which is obtained from different piston head design, combustion chamber types and air fuel injection methods. Turbulent motion of charge inside a combustion chamber is necessary for compete breakdown and mixing of fuel with air.

What is the function of air swirl?

Swirl, possibly in combination with tumble and squish, is designed to promote large-scale transport of fuel-air mixture during fuel injection and to enhance the late-cycle mixing. In general, swirling flow can increase flame propagation speed and reduce cycle-to-cycle variations.

What is combustion swirl?

Swirling flows have been commonly used for a number of years for the stabilization of high-intensity combustion processes. The Cyclone Combustion Chamber. Here air is injected tangentially into a large, usually, cylindrical chamber and exhausts through a centrally located exit hole in one end.

Why is turbulence important in combustion?

Turbulence mixes fluids efficiently, bringing reactants together that can ignite and burn. Any analysis of turbulent-combustion phenomena must deal with the flow and chemical reactions as coupled processes.

What do you mean by air swirl?

Swirl is an important flow pattern of air motion commonly found in diesel engines; it not only affects the fuel-air mixing and combustion processes, but also has a significant impact on heat transfer, combustion quality, and engine-raw emissions. Swirl is used to describe circulation about the cylinder axis.

How is air circulation swirl in liners achieved?

This can be achieved by supplying air in the cylinder via angled hole in the liner to create swirling motion for better mixing. If the cylinder components such as piston, piston ring, or liner are worn out or leaky, the rated compression pressure will not be achieved and the combustion will not be efficient.

What is swirl combustion chamber?

an internal combustion engine (usually diesel) in which the mixture of fuel occurs through intensive swirling of the air entering a spherical combustion chamber, which is connected with the engine cylinder by a tangential canal.