News

Fine atomization spray, chemical fiber spinneret, spinneret

中大
Check category

Atomization characteristics of atomization nozzle

(Summary description)Atomization characteristics refer to the influence law of nozzle structure, working parameters, physical properties of atomizer and atomization medium on nozzle atomization performance. In order to comprehensively evaluate the atomization performance of the nozzle, a number of index parameters are proposed, mainly including: atomization fineness, atomization uniformity, and atomization cone angle.

Atomization characteristics of atomization nozzle

(Summary description)Atomization characteristics refer to the influence law of nozzle structure, working parameters, physical properties of atomizer and atomization medium on nozzle atomization performance. In order to comprehensively evaluate the atomization performance of the nozzle, a number of index parameters are proposed, mainly including: atomization fineness, atomization uniformity, and atomization cone angle.

Atomization characteristics refer to the influence law of nozzle structure, working parameters, physical properties of atomizer and atomization medium on nozzle atomization performance. In order to comprehensively evaluate the atomization performance of the nozzle, a number of index parameters are proposed, mainly including: atomization fineness, atomization uniformity, and atomization cone angle.

Atomization fineness

The size of the droplets after atomization reflects the particle fineness of atomization and is an important indicator for evaluating the quality of atomization. Generally speaking, the finer the particles of the mist, the easier it is to heat, evaporate and burn. However, too fine atomization is not good. The fuel will be taken away by the airflow immediately after being ejected from the nozzle, forming an overly thick mixture in a certain area; where the oil droplets cannot be shot, the concentration of the mixture is very low. This distribution of the concentration field will narrow the range of combustion stability and reduce combustion efficiency. Since the size of the droplet diameter is not uniform, the maximum and minimum can sometimes differ by 50-100 times, so the concept of the average droplet diameter can only be used to express the atomization fineness. People have proposed a variety of calculation methods for the average diameter, the most commonly used are the mass median diameter (MMD) and the Soter average diameter (SMD or D32).

D32 is equivalent to the ratio of the volume of all droplets in the liquid mist to the total surface area. It truly reflects the evaporation conditions of the droplet group. Therefore, it is of great significance for evaluating the quality of atomization and is widely used as an important evaluation index for fuel nozzles.

Atomization uniformity

Atomization uniformity refers to the uniformity of the oil droplet size after fuel atomization. If the uniformity of atomization is poor, the number of large droplets is large, which is detrimental to combustion. However, it is unreasonable to be too uniform, because it will make most of the oil droplets concentrate in a certain area, and the volume of the combustion chamber will not be fully utilized, and the combustion stability will also be affected. At present, the distribution of droplet size is often used to describe the uniformity of atomization.

Atomization cone angle

The fuel spray torch ejected from the nozzle is in the shape of a hollow cone, which is composed of many small droplets suspended in the surrounding air or moving in it. Generally, the angle between the outlet of the nozzle and the two tangents of the outer envelope of the spray torch is defined as the spray cone angle. The size of the spray cone angle largely determines the distribution of fuel in the combustion space. The spray cone angle should be selected according to the size of the combustion chamber and the mixing conditions of fuel and air. The larger nozzle cone angle can not only fully supply the fuel into the air, but also can suck more air from the surrounding, so that it can enter the spray torch to participate in the fuel crushing process. However, an excessively large cone angle will inject fuel onto the flame tube wall, causing coke deposits and incomplete combustion. Of course, the cone angle should not be too small, otherwise the fuel droplets cannot be effectively distributed to the entire combustion chamber space, and excessive injection into the oxygen-deficient recirculation zone will cause poor mixing with air, carbon precipitation, and exhaust gas emission. smoke. In addition, the size of the spray cone angle also affects the length of the flame shape. If the angle is larger, the flame will be short and thick; otherwise, it will be thin and long.

Zhuji Haihang Misting Equipment Co., Ltd.

No. 462, Zhongyang RD., Diankou Town, Zhuji city, Zhejiang Province, China
Tel:
0086-575-87555003
Hotline:4008255003
E-mail:info@hmisting.com

copyright   ZHUJI HAIHANG MISTING EQUIPMENT CO., LTD.    浙ICP备19042661号-1