Results show strong non-linear interaction in a fluid with a relative high Prandtl number within the intermediate range of modulated frequency. With the mathematical model, so verified by experimental measurements, numerical simulations are carried out to study the effects of modulation frequency and Prandtl number on the fluid flow. Computed results compare well with experimental measurements for various conditions.

In parallel with numerical development, an experimental system is setup where oscillating wall temperatures are prescribed to produce modulated temperature gradients and the velocity fields are measured by a laser-based particle image velocimetry (PIV) system. Numerical computations are presented, which are based on the finite element solution of the transient Navier–Stokes and energy balance equations, along with appropriate thermal boundary conditions or time-varying gravity forces. This paper presents an investigation on natural convection in a cavity with imposed modulated thermal gradients or modulated gravity forces.

Infinity symbol in tecplot