Atomization technology has almost covered all industrial sectors, such as transportation, agricultural production, as well as the daily lives of the people, in addition to the combustion of various fuels (gas, liquid and solid fuels), atomizing technology also has a wide range of applications in the industries such as non-combustion catalytic granulation, food processing, powder coating pesticide spraying aspects and spray gun nozzle. The so-called liquid atomization means in the effect of the applied energy, the liquid is changed into a liquid fog or other small droplets in the gas environment. Atomization mechanism has been interpreted in a number of ways, such as aerodynamic interference theory, pressure shock theory, the turbulent perturbations theory, air turbulence theory, boundary conditions mutations theory.
Five theories of atomization technology
First, aerodynamic interference theory, Castleman first proposed the aerodynamic interference theory. He believes that due to aerodynamic interference effects between the jet and the surrounding gas, instability fluctuations are produced on the jet surface. With the increase of speed, surface length affected by the unstable wave is shorter and shorter, until microns and then the jet is spread into the mist. Second, Pressure oscillation theory, this theory observes that liquid supply system pressure oscillation has impact on the atomization process. Thus, according to the prevalent pressure oscillations in the general injection system, we can ensure it plays an important role in atomization of atomizing nozzle.Third, Turbulent disturbance theory, this theory believes jet atomization process occurs inside the nozzle, and fluid turbulence may play an important role. Someone also suggest that the radial component velocity fluid movement as turbulent pipe flow nozzle at the nozzle exit resulting in the atomization. Fourth, Air disturbance theory, it holds the opposite attitude to turbulent disturbance theory, it believes that the large-amplitude pressure disturbances in the fuel injection system is caused by atomization. Fifth, Boundary conditions mutation theory, the boundary conditions mutations holds the opinion that at the mutations happen in the nozzle outlet and the boundary condition of the liquid (internal stress). Conclusion of five nozzle theories There are inadequacies in the five nozzles mechanism hypothesis and even conflicting. Most scholars, such as Bracco FV supports aerodynamic interference theory. The hypotheses fully explain the low speed jet breakup and the high-speed jet, and it can be used as the basic cause of the atomization. Now the fuel spray atomization mechanism is researched in two ways at home and abroad: first, use numerical techniques to create a variety of hypotheses model numerical modeling studies; the other hand, use advanced photoelectric test technology to capture the details of the atomization process , in order to provide support for the hypothesis.
www.spray-nozzle.net
We are a high tech company which combined R&D, sales and production together. Our company has become one of the biggest manufacturers of spray nozzle in China after a development of more than 11 years. All the products have passed the ISO9001 and ISO14001 quality and enviroment certificate, which can satisfy the reuqirements of our customers.
This article is come from: http://pannel.aluminum-machine.com/uncategorized/technology-development-of-atomizing-nozzle.htm
No comments:
Post a Comment