The effect of extensional viscosity on the effervescent atomization of polyacrylamide solutions

M. Ochowiak; L. Broniarz-Press; S. Rozanska; J. Rozanski

Journal of Industrial and Engineering Chemistry, Vol.18, No.6, 2028-2035, November, 2012

DOI10.1016/j.jiec.2012.05.023 Export Citation

The effect of extensional viscosity on the effervescent atomization of polyacrylamide solutions

M. Ochowiak^†, L. Broniarz-Press, S. Rozanska, and J. Rozanski

Department of Chemical Engineering and Equipment, Faculty of Chemical Technology, Poznan University of Technology, pl. M. Sklodowskiej-Curie 2, PL 60-965 Poznan, Poland

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The paper contains the results of experimental investigation of the rheological characteristics and atomization process of solutions of polymer. The solutions had the polyacrylamide (PAA) mass fraction in the range from 0.0025 to 0.001. The solutions of polymer have non-Newtonian characteristics. It has been shown that shear viscosity increases with polymer concentration in the solutions. Extensional viscosity increases with increasing extensional rates. The Trouton ratio for glycerol solution is about 5.4. The Trouton ratios observed for the polymer solutions increase with increasing shear (extensional) rate and polymer concentration in solution. This paper draws a link between the extensional viscosity and the effervescent atomization. The polymer addition to cause the solution viscosity to increase, thereby different disintegration of liquid could be obtained. During two-phase atomization process of polymer solutions the characteristic stages in spray development have been observed. The phenomenon of the formation of ‘‘beads on a string’’ for solutions with low concentrations of polymer has been observed. The thin filament between droplets and/or bubbles was observed for all polymer solutions studied. Analysis of photos on forming the droplets showed that droplets diameter increases with increasing of polymer concentration. In all twophase systems studied the Sauter mean diameter decreases with increase of gas to liquid flow rates ratio value. Sauter mean diameter is dependent on gas and liquid flow rates and the liquid properties. It is particularly important in processes in which the value of the average droplet diameter plays a key role. High molecular polymers added to a solvent involve the changes in the rheological properties of liquid and the disintegration of liquid jets and/or sheets. The effect of extensional viscosity on the droplets formation has been shown. The data obtained in the present study have shown that the decreasing of the extensional viscosity of the solution will reduce the spray’s Sauter mean diameter. The results may be used, for example, to verify numerical models or in comparison with similar atomization processes.

Keywords:Rheology;Extensional viscosity;Trouton ratio;Spray;Effervescent atomizer

[References]

Lefebvre AH, Atomization and Sprays, Hemisphere Publishing Corporation, New York (1989)
Sovani SD, Sojka PE, Lefebvre AH, Progress in Energy and Combustion Science., 27, 483 (2001)
Jagannathan TK, Nagarajan R, Ramamurthi K, Chem. Eng. Process., 50(3), 305 (2011)
Harrison GM, Mun R, Cooper G, Boger DV, J. Non-Newton. Fluid Mech., 85(1), 93 (1999)
Orzechowski Z, Prywer J, Liquids Atomization, Wydawnictwa Naukowo Techniczne, Warszawa, (in Polish). (1991)
Orzechowski Z, Prywer J, The Preparation and Use of Spray, Wydawnictwa Naukowo Techniczne, Warszawa,(in Polish). (2008)
Lund MT, Sojka PE, Lefebvre AH, Gosselin PG, Atomization and Sprays., 3, 77 (1993)
Satapathy MR, Sovani SD, Sojka PE, Gore JP, Eckerle WA, Crofts JD, in: Proceedings of the Technical Meeting of the Central States Section of the Combustion Institute, from [2]., 76 (1998)
Butler Ellis MC, Tuck CR, Crop Protection., 18, 101 (1999)
Miller PCH, Butler Ellis MC, Crop Protection., 19, 609 (2000)
Geckler SC, Sojka PE, Journal of Fluids Engineering., 130, 1 (2008)
Mun RP, Byars JA, Boger DV, J. Non-Newton. Fluid Mech., 74(1-3), 285 (1998)
Mun RP, Young BW, Boger DV, J. Non-Newton. Fluid Mech., 83(1-2), 163 (1999)
Geckler SC, Effervescent atomization of visco-elastic liquids, M.Sc. Thesis, Purdue University, from [2]. (1994)
Thompson JC, Rothstein JP, J. Non-Newton. Fluid Mech., 147(1-2), 11 (2007)
Geckler SC, Sojka PE, American Society of Mechanical Engineers., 270, 109 (1993)
Geckler SC, Sojka PE, in: Proceedings of the 7th Annual Conference on Liquid Atomization and Spray Systems, Bellevue, Washington, 181 (1994)
Lee WY, Sojka PE, American Society of Mechanical Engineers., 270, 129 (1996)
Padmanabhan M, Journal of Food Engineering., 25, 311 (1995)
Broniarz-Press L, Ochowiak M, Woziwodzki S, International Journal of Heat and Fluid Flow., 31, 651 (2010)
Kim DY, Kowach GR, Johnson DW, Bhandarkar S, Du H, Journal of Non-Crystalline Solids., 342, 18 (2004)
Galindo Rosales FJ, Rubio Hernandez FJ, Velazquez Navarro JF, Annual Transactions of the Nordic Rheology Society., 15, 1 (2007)
Buckner HE, Sojka PE, Atomization and Sprays., 1, 239 (1991)
Sutherland JJ, Sojka PE, Plesniak MW, Atom. Sprays, 7(4), 383 (1997)
McKinley GH, Rheology Reviews, The British Society of Rheology, Aberystwyth, Wales (2005)

[1] Lefebvre AH, Atomization and Sprays, Hemisphere Publishing Corporation, New York (1989)

[2] Sovani SD, Sojka PE, Lefebvre AH, Progress in Energy and Combustion Science., 27, 483 (2001)

[3] Jagannathan TK, Nagarajan R, Ramamurthi K, Chem. Eng. Process., 50(3), 305 (2011)

[4] Harrison GM, Mun R, Cooper G, Boger DV, J. Non-Newton. Fluid Mech., 85(1), 93 (1999)

[5] Orzechowski Z, Prywer J, Liquids Atomization, Wydawnictwa Naukowo Techniczne, Warszawa, (in Polish). (1991)

[6] Orzechowski Z, Prywer J, The Preparation and Use of Spray, Wydawnictwa Naukowo Techniczne, Warszawa,(in Polish). (2008)

[7] Lund MT, Sojka PE, Lefebvre AH, Gosselin PG, Atomization and Sprays., 3, 77 (1993)

[8] Satapathy MR, Sovani SD, Sojka PE, Gore JP, Eckerle WA, Crofts JD, in: Proceedings of the Technical Meeting of the Central States Section of the Combustion Institute, from [2]., 76 (1998)

[9] Butler Ellis MC, Tuck CR, Crop Protection., 18, 101 (1999)

[10] Miller PCH, Butler Ellis MC, Crop Protection., 19, 609 (2000)

[11] Geckler SC, Sojka PE, Journal of Fluids Engineering., 130, 1 (2008)

[12] Mun RP, Byars JA, Boger DV, J. Non-Newton. Fluid Mech., 74(1-3), 285 (1998)

[13] Mun RP, Young BW, Boger DV, J. Non-Newton. Fluid Mech., 83(1-2), 163 (1999)

[14] Geckler SC, Effervescent atomization of visco-elastic liquids, M.Sc. Thesis, Purdue University, from [2]. (1994)

[15] Thompson JC, Rothstein JP, J. Non-Newton. Fluid Mech., 147(1-2), 11 (2007)

[16] Geckler SC, Sojka PE, American Society of Mechanical Engineers., 270, 109 (1993)

[17] Geckler SC, Sojka PE, in: Proceedings of the 7th Annual Conference on Liquid Atomization and Spray Systems, Bellevue, Washington, 181 (1994)

[18] Lee WY, Sojka PE, American Society of Mechanical Engineers., 270, 129 (1996)

[19] Padmanabhan M, Journal of Food Engineering., 25, 311 (1995)

[20] Broniarz-Press L, Ochowiak M, Woziwodzki S, International Journal of Heat and Fluid Flow., 31, 651 (2010)

[21] Kim DY, Kowach GR, Johnson DW, Bhandarkar S, Du H, Journal of Non-Crystalline Solids., 342, 18 (2004)

[22] Galindo Rosales FJ, Rubio Hernandez FJ, Velazquez Navarro JF, Annual Transactions of the Nordic Rheology Society., 15, 1 (2007)

[23] Buckner HE, Sojka PE, Atomization and Sprays., 1, 239 (1991)

[24] Sutherland JJ, Sojka PE, Plesniak MW, Atom. Sprays, 7(4), 383 (1997)

[25] McKinley GH, Rheology Reviews, The British Society of Rheology, Aberystwyth, Wales (2005)