The stability of swirling flows with a heat source

The absolute instability of a Rankine vortex with an axial flow and paraxial heat source is investigated. The dispersion relation for vortex modes is derived analytically. The dependence of dispersion properties of the media on control parameters such as swirl parameter $S$, velocity $a$, and heat source power (density parameter $Q$) is studied. The frequency of helical waves increases and the increment decreases with increasing heat source power, accompanied by a decrease in the width of the neutral stability region. Numerical analysis also suggests that one of the dispersion curve branches could include an instability region of a parametric nature.