Numerical simulation of flow in swirl injector for power-law fluid
Numerical simulation of flow in swirl injector for power-law fluid
-
摘要: In order to investigate the flow characteristics of swirl injectors for gelled propellants, which actually behaved as non-Newtonian power-law fluid, a swirl axisymmetric model was established to solve Navier-Stokes equations and VOF (volume of fluid) equation, and the power-law constitutive equation was used to describe the rheology characteristics of the gelled propellants. The film thickness and velocity distribution in the swirl injector under different flow conditions were studied numerically. The simulation results show that the increased geometry characteristic parameter of the swirl injector contributes to the decrease of liquid film thickness. The liquid film thickness is almost independent of the pressure drop. The rheologic parameters have great influences on the inner flow of swirl injector: by increasing the fluid consistency index K and power index n, both the axial and the swirl velocities decrease dramatically; higher fluid consistency index K and power index n make the liquid film thickness increase. When the viscosity is large enough, the air core in the injector would vanish.Abstract: In order to investigate the flow characteristics of swirl injectors for gelled propellants, which actually behaved as non-Newtonian power-law fluid, a swirl axisymmetric model was established to solve Navier-Stokes equations and VOF (volume of fluid) equation, and the power-law constitutive equation was used to describe the rheology characteristics of the gelled propellants. The film thickness and velocity distribution in the swirl injector under different flow conditions were studied numerically. The simulation results show that the increased geometry characteristic parameter of the swirl injector contributes to the decrease of liquid film thickness. The liquid film thickness is almost independent of the pressure drop. The rheologic parameters have great influences on the inner flow of swirl injector: by increasing the fluid consistency index K and power index n, both the axial and the swirl velocities decrease dramatically; higher fluid consistency index K and power index n make the liquid film thickness increase. When the viscosity is large enough, the air core in the injector would vanish.
-
Key words:
- numerical simulation /
- gelled propellants /
- power-law fluid /
- swirl injector /
- inner flow
-
[1] Lefebvre A H.Atomization and Spray[M].New York: Hemisphere Publishing Corporation,1989. [2] Chinn J J.An appraisal of swirl atomizer inviscid flow analysis,part 1: the principle of maximum flow for a swirl atomizer and its use in the exposition and comparison of early flow analyses[J].Atomization and Sprays,2009,19(3):263-282. [3] Suyari M,Lefebvre A H.Film thickness measurements in a simplex swirl atomizer[J].Journal of Propulsion and Power,1986,2(6):528-533. [4] Fu Q,Yang L,Qu Y.Measurement of annular liquid film thickness in an open-end swirl injector[J].Aerospace Science and Technology,2010,15(2):117-124. [5] Kim S,Kim D,Khil T,et al.Effect of geometry on the liquid film thickness and formation of air core in a swirl injector.AIAA 2007-5460,2007. [6] Wang D,Ma Z,Jeng S M,et al.Experimental study on large-scale simplex nozzle.AIAA 1999-2401,1999. [7] Kenny R J,Hulka J R,Moser M D,et al.Effect of chamber backpressure on swirl injector fluid mechanics[J].Journal of Propulsion and Power,2009,25(4):902-913. [8] Liao Y,Sakman A T,Jeng S M,et al.A comprehensive model to predict simplex atomizer performance[J].Journal of Engineering for Gas Turbine and Power,1999,121(2): 285-294. [9] Dash S K,Halder M R,Peric M,et al.Formation of air core in nozzles with tangential entry[J].Journal of Fluids Engineering,2001,123(4): 829-835. [10] Von Kampen J,Alberio F,Ciezki H K.Spray and combustion characteristics of aluminized gelled fuels with an impinging jet injector[J].Aerospace Science and Technology,2007,11(1):77-83. [11] Mansour A,Chigier N.Air-blast atomization of non-Newtonian liquids[J].J. Non-Newtonian Fluid Mech.,1995,58(2/3):161-194. [12] Chernov V,Natan B.Effect of periodic disturbances on non-Newtonian fluid sprays[J].Atomization and Sprays,2008,18(8):723-738. -
点击查看大图
计量
- 文章访问数: 1801
- HTML浏览量: 70
- PDF量: 511
- 被引次数: 0

下载: