#### Filter Results:

#### Publication Year

1993

2010

#### Publication Type

#### Co-author

#### Key Phrase

#### Publication Venue

#### Organism

Learn More

- N J Balmforth, G R Ierley, W R Young
- 2001

Analytical estimates of the rate at which energy is extracted from the barotropic tide at topography and converted into internal gravity waves are given. The ocean is idealized as an inviscid, vertically unbounded fluid on the f plane. The gravity waves are treated by linear theory and freely escape to z ϭ ϱ. Several topographies are investigated: a… (More)

- N J Balmforth, P Cvitanovi´c, G R Ierley, E A Spiegel, And G Vattay
- 1993

" The high average vorticity that is known to exist in turbulent motion is caused by the extension of vortex filaments in an eddying fluid. "

- N J Balmforth, R V Craster
- 1998

Thin-layer theory is developed for Bingham plastic uids; the speciic case of a uid owing down an inclined plane is considered. In contrast to previous work it is indicated how the Bingham model leads directly to a self-consistent thin-layer theory; this does not rely upon adopting a bi{viscous approximation. The theory describes the uid in terms of regions… (More)

We report a traveling wave instability in low Reynolds number flows of aqueous concentrated suspensions of corn starch. The experimental observations are difficult to reconcile with theoretical predictions based on simple rheological models which indicate that flows are stable at low Reynolds number.

- N J Balmforth, A Jacobson, A Provenzale
- 1999

The dynamics of a globally coupled, logistic map lattice is explored over a parameter plane consisting of the coupling strength, ⑀, and the map parameter, a. By considering simple periodic orbits of relatively small lattices, and then an extensive set of initial-value calculations, the phenomenology of solutions over the parameter plane is broadly… (More)

- N J Balmforth, P J Morrison
- 1998

We derive a condition that is necessary and sufficient for the instability of inviscid, two-dimensional, plane parallel, shear flow with equilibrium velocity profiles that are monotonic, real analytic, functions of the cross stream coordinate. The analysis, which is based upon the Nyquist method, includes a means for delineating the possible kinds of… (More)

- N J Balmforth, W R Young
- 1997

A reduced description of disturbances on marginally stable shear flows is presented. The system is the Boussinesq equation coupled to a critical-layer, vorticity equation. The reductive perturbation theories used by physicists typically fall into two classes: adiabatic elimination of strongly damped variables in dissipative systems, or averaging over fast… (More)

- N J Balmforth, R V Craster, P Perona, A C Rust, R Sassi

We present a theoretical and experimental analysis of the dam break of a vis-coplastic fluid in a horizontal channel. A shallow, slow fluid model based on the Herschel-Bulkley constitutive law allows one to characterize the early and late stages of the flow, the final state and the dependence on yield stress and nonlinear viscosity. A particular diagnostic… (More)