Vorticity and curvature at a free surface

1998 ◽  
Vol 356 ◽  
pp. 149-153 ◽  
Author(s):  
MICHAEL S. LONGUET-HIGGINS

For two-dimensional flow there is a simple relation between the vorticity at a stress-free surface and the surface curvature. In this note the relation is generalized to flow in three dimensions. It is shown that in addition to a component of vorticity perpendicular to the flow there is also a component parallel to the direction of flow. The latter vanishes only at an umbilical point or when the flow is in one of the two principal directions of curvature.

2012 ◽  
Vol 24 (1) ◽  
pp. 77-101 ◽  
Author(s):  
A. DELİCEOĞLU

Topology of two-dimensional flow associated with degenerate dividing streamline on a free surface is analysed from a topological point of view by considering the critical point concept. Streamline patterns and their bifurcations in the vicinity of a free surface were investigated by Brøns (Brøns, M. (1994) Topological fluid dynamics of interfacial flows. Phys. Fluids6, 2730–2736). Brøns's work is extended to the case of a stream function, including the fourth-order normal form approach. From this, a complete description of bifurcations which can occur in two-dimensional incompressible flow is obtained up to codimension three. The theory is applied to the patterns found numerically in a roll coater.


1978 ◽  
Vol 22 (03) ◽  
pp. 193-202 ◽  
Author(s):  
Odd M. Faitinsen

A numerical method for the study of sloshing in tanks with two-dimensional flow is presented. The solution satisfies the exact nonlinear free-surface conditions. To avoid difficulties with transients, artificial damping is introduced. Comparison with a linear analytical solution, derived in this publication, shows that the numerical method gives reasonable results. Comparison with an approximate nonlinear analytical method, derived earlier by the author, indicates that the artificial damping leads to difficulties in special cases.


1999 ◽  
Vol 2 (3) ◽  
pp. 251-262
Author(s):  
P. Gestoso ◽  
A. J. Muller ◽  
A. E. Saez

Author(s):  
Gabriel Machado dos Santos ◽  
Ítalo Augusto Magalhães de Ávila ◽  
Hélio Ribeiro Neto ◽  
João Marcelo Vedovoto

Open Physics ◽  
2020 ◽  
Vol 18 (1) ◽  
pp. 139-148
Author(s):  
Shiyang Liu ◽  
Xuefu Zhang ◽  
Feng Gao ◽  
Liangwen Wei ◽  
Qiang Liu ◽  
...  

AbstractWith the rapid development of traffic infrastructure in China, the problem of crystal plugging of tunnel drainage pipes becomes increasingly salient. In order to build a mechanism that is resilient to the crystal plugging of flocking drainage pipes, the present study used the numerical simulation to analyze the two-dimensional flow field distribution characteristics of flocking drainage pipes under different flocking spacings. Then, the results were compared with the laboratory test results. According to the results, the maximum velocity distribution in the flow field of flocking drainage pipes is closely related to the transverse distance h of the fluff, while the longitudinal distance h of the fluff causes little effect; when the transverse distance h of the fluff is less than 6.25D (D refers to the diameter of the fluff), the velocity between the adjacent transverse fluffs will be increased by more than 10%. Moreover, the velocity of the upstream and downstream fluffs will be decreased by 90% compared with that of the inlet; the crystal distribution can be more obvious in the place with larger velocity while it is less at the lower flow rate. The results can provide theoretical support for building a mechanism to deal with and remove the crystallization of flocking drainage pipes.


Sign in / Sign up

Export Citation Format

Share Document