On the Spiral Roll State in Heat Convection between Non-Rotating Concentric Double Spherical Boundaries

TL;DR

This paper numerically investigates the single-arm spiral roll state in heat convection between non-rotating concentric spherical boundaries, revealing its existence in thicker gaps and characterizing it as a traveling wave with constant angular velocity.

Contribution

It provides a detailed numerical analysis of the spiral roll state, extending previous findings to thicker gaps and identifying it as a traveling wave solution.

Findings

Spiral roll state exists in thicker gaps.

State characterized as a traveling wave with constant angular velocity.

Numerical confirmation of previous theoretical predictions.

Abstract

The single-arm spiral roll state in the system of Boussinesq fluid confined between non-rotating double concentric spherical boundaries with an opposing temperature gradient previously reported by Zhang et al.(Phys. Rev. E, v66, 055203, 2002) has been numerically investigated in detail. It is presented that the state can exist even in a relatively thicker gap rather than that used in our previous reports as a travelling wave solution with a finite constant angular velocity.