Spray cone angle

Spray cleaning, of metal surfaces, 16 213 Spray coating processes, 7 23, 68-76 economic aspects, 7 75-76 Spray column absorbers, 1 27 Spray cone angle, 23 187 Spray correlations, 23 189-192 Spray deposition, of metal-matrix composites, 16 173 Spray-dried products, 11 542-543 Spray-dried resins, production of,... 

One of the limitations of plain-orifice atomizers is the narrow spray cone generated. For most practical applications, large spray cone angles are desired. To achieve a wide spray cone, a simplex, i.e.,... 

Various correlations for mean droplet size generated using pressure-swirl and fan spray atomizers are summarized in Tables 4.4 and 4.5, respectively. In the correlations for pressure-swirl data, FN is the Flow number defined as FN = ml/APlpl) )5, l0 and d0 are the length and diameter of final orifice, respectively, ls and ds are the length and diameter of swirl chamber, respectively, Ap is the total inlet ports area, /yds the film thickness in final orifice, 6 is the half of spray cone angle, and Weyis the Weber number estimated with film... 

As ambient air pressure is increased, the mean droplet size increases 455 " 458] up to a maximum and then turns to decline with further increase in ambient air pressure. ] The initial rise in the mean droplet size with ambient pressure is attributed to the reduction of sheet breakup length and spray cone angle. The former leads to droplet formation from a thicker liquid sheet, and the latter results in an increase in the opportunity for droplet coalescence and a decrease in the relative velocity between droplets and ambient air due to rapid acceleration. At low pressures, these effects prevail. Since the mean droplet size is proportional to the square root of liquid sheet thickness and inversely proportional to the relative velocity, the initial rise in the mean droplet size can be readily explained. With increasing ambient pressure, its effect on spray cone angle diminishes, allowing disintegration forces become dominant. Consequently, the mean droplet size turns to decline. Since ambient air pressure is directly related to air density, most correlations include air density as a variable to facilitate applications. Some experiments 452] revealed that ambient air temperature has essentially no effect on the mean droplet size. 

Several empirical relations have been proposed to express drop size in terms of the operating variables. One suitable for small atomisers with 85° spray cone angles, at atmospheric pressure is(34) ... 

Inlet air dew point Nozzle spray cone angle... 

The rate of depth of penetration of a spray tip into a chamber is found by Gelalles (4C) to be a function of the ratio of length to diameter. Using pressures ranging from 2000 to 8000 pounds per square inch and a plain stem ahead of the orifice, maximum penetration rates have been obtained for L/D ratios between 4 and 6. The spray cone angle increases with the ratio of the orifice area to the groove area. Others who have conducted detailed investigations on spray formation include Doble (3C), Lee (9C, IOC), and Rothrock and Waldron (20C). 

Reasonable correlations of combustion efficiency with fuel spray momentum and spray energy in two different combustors have been shown to hold over a range of altitude-engine idling conditions 133). As different curves were obtained with different injector nozzles, spray-cone angle was thought to be a factor. Further work showed that efficiency did correlate closely with expressions representing the spray momentum or... 

Frolov Are your results sensitive to the type of fuel injector used I mean not only the drop size distribution, but the effect of spray cone angle, tip penetration length, and other parameters. 

Langrish, T. A. G. and Zbicinski, I. 1994. The effect of air inlet geometry and spray cone angle on the wall deposition rate in spray dryers. Trans. I. Chem. E. 72 420-430. 

Chinn, J. J. An appraisal of swirl atomizer inviscid internal flow analysis. Part 2, Inviscid spray cone angle and comparison of inviscid method with experimental results for discharge coefficient, air core radius, and spray angle. Atom. Sprays 19, 283-308 (2009). 

The spray cone angle is inversely proportional to the nozzle constant [4]. The effective spray cmie angle increases with increase in the injectimi pressure or liquid mass flow rate for all fluid viscosities and different nozzle geometries [20]. At the same time, the breakup point of the sheet approaches the nozzle, as shown in Fig. 33.5 [44]. An increase in the length/diameter ratio of the final discharge orifice reduces the spray cone angle. Liquid viscosity reduces the spray cone angle [20]. 

N. K. Rizk, A. H. Lefebvre, Prediction of velocity coefficient and spray cone angle for simplex swirl atomizers, in Proceedings of the Third International Conference on Liquid Atomization and Spray Systems, London, p. lllc/2/1 (1985b). 

S. K. Chen, A. H. Lefebvre, J. Rollbuhler, Factors influencing the effective spray cone angle of pressure swirl atomizers, ASME J. Eng. Gas Turbine Power 114, 97 (1992). 

A. Datta, S. K. Som, Numerical prediction of air core diameter, coefficient of discharge and spray cone angle of a swirl spray pressure nozzle, Int. J. Heat Fluid Flow 21, 412 (2000). 

Here, X is the area fraction of air core at the nozzle exit and a is spray cone angle. For a swirling conical melt-tin sheet, the spray cone angle increases nearly linearly from a = 15-55° with an increase in pressure differential (ApO on the liquid from Api = 0.4 MPa to 0.8 MPa [4, 9]. 

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