Coefficient of discharge and spray cone angle of a pressure nozzle with combined axial and tangential entry of power-law fluids |
| |
Authors: | G Biswas and S K Som |
| |
Institution: | (1) Department of Mechanical Engineering, Indian Institute of Technology, 721302 Kharagpur, India |
| |
Abstract: | Flows of incompressible, time-independent purely viscous power-law fluids through pressure nozzle with combined axial and
tangential entry are analysed. Theoretical predictions of coefficient of discharge and spray cone angle are made through an
approximate analytical solution of hydrodynamics of flow inside the nozzle. In the converging section of the nozzle, the boundary
layer equations have been derived with modified order approximation O(δ/R)≈1, O(δ
2/R
2)≪1] of Navier-Stokes equations for a better accuracy. Smoother attainment of the free-stream condition at the edge of the
boundary layer is ensured by requiring the appropriate shear rate terms, compatible with the above order analysis, to be zero.
The pertinent independent input parameters which govern the flow field are the generalized Reynolds number at inlet to the
nozzle based on the tangential velocity of injection
, the ratio of the axial-to-tangential velocity at the inlet to the nozzle V
R
, the flow behaviour index of the fluid n, the length-to-diameter ratio of the swirl chamber L
1/D
1, the spin chamber angle 2α and the orifice-to-swirl-chamber-diameter ratio D
2/D
1. Experiments reported in the paper corroborate the qualitative trends of analytical results. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|