Empirical scaling of antisymmetric stratified wakes

Gallet, S.; Meunier, Patrice; Spedding, Geoffrey

doi:10.1016/j.jfluidstructs.2006.04.017

Cited by 2 publications

(2 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The model could be extended to more specialised cases, such as bluff body wakes with an angle of attack [31], and to the particular case of exactly momentumless wakes. In both cases, the mean profiles are not simple Gaussians and it would be interesting to test other scaling functions.…”

Section: Rementioning

confidence: 99%

Self-preservation in stratified momentum wakes

2006

View full text Add to dashboard Cite

A general model is described for drag wakes in a linearly stratified fluid, based on the selfpreservation of the flow. It is assumed that the buoyancy-controlled self-similar wake expands in the horizontal direction due to turbulent diffusion and in the vertical direction due to viscous diffusion. The mean characteristics of the wake (height, width and velocity defect) are analytically derived and show good agreement with existing data from experimental and numerical results.Moreover, the three regimes previously found in the literature that characterise different dynamical phases of the wake evolution are recovered, and two new regimes are found. The model allows for prediction of characteristic length and velocity scales at the high Reynolds numbers of large-scale applications of geophysical and naval origin.

show abstract

Section: Rementioning

confidence: 99%

Self-preservation in stratified momentum wakes

2006

View full text Add to dashboard Cite

show abstract

“…also found that a momentumless propelled wake at a small angle of attack generates a threelobed vorticity structure and the velocity becomes self-similar, retaining the initially asymmetric profile. The asymmetric momentumless case introduced in is discussed in detail by Gallet, Meunier & Spedding (2006) who found that both the wake width and maximum velocity decayed at the same rate as a momentum wake when the velocity is normalized appropriately. As a result of their observation that the wake is strongly sensitive to small amounts of excess momentum as well as the angle of attack of the body, question whether a momentumless wake ever exists in practice.…”

Section: Introductionmentioning

confidence: 99%

Simulation of a propelled wake with moderate excess momentum in a stratified fluid

Stadler

Sarkar

2011

J. Fluid Mech.

View full text Add to dashboard Cite

Direct numerical simulation is used to simulate the turbulent wake behind an accelerating axisymmetric self-propelled body in a stratified fluid. Acceleration is modelled by adding a velocity profile corresponding to net thrust to a self-propelled velocity profile resulting in a wake with excess momentum. The effect of a small to moderate amount of excess momentum on the initially momentumless self-propelled wake is investigated to evaluate if the addition of excess momentum leads to a large qualitative change in wake dynamics. Both the amount and shape of excess momentum are varied. Increasing the amount of excess momentum and/or decreasing the radial extent of excess momentum was found to increase the defect velocity, mean kinetic energy, shear in the velocity gradient and the wake width. The increased shear in the mean profile resulted in increased production of turbulent kinetic energy leading to an increase in turbulent kinetic energy and its dissipation. Slightly larger vorticity structures were observed in the late wake with excess momentum although the differences between vorticity structures in the self-propelled and 40 % excess momentum cases was significantly smaller than suggested by previous experiments. Buoyancy was found to preserve the doubly inflected velocity profile in the vertical direction, and similarity for the mean velocity and turbulent kinetic energy was found to occur in both horizontal and vertical directions. While quantitative differences were observed between cases with and without excess momentum, qualitatively similar evolution was found to occur.

show abstract

Empirical scaling of antisymmetric stratified wakes

Cited by 2 publications

References 7 publications

Self-preservation in stratified momentum wakes

Self-preservation in stratified momentum wakes

Simulation of a propelled wake with moderate excess momentum in a stratified fluid

Contact Info

Product

Resources

About