Rotational Currents

An analysis of rotational currents is made for the case of small oblateness and constant angular velocity, ω = const. Contrary to von Zeipel's paradox, the average energy generation over a level surface of the rotating star is subject to no restrictions ; the balancing convective circulation is derived by developing Eddington's method in more detail; a complete system of circulation is calculated for a particular model. As compared with the speed of nuclear reactions, the mixing efficiency of the rotational currents for $$\omega \,=\,{10}^{-4}$$ (or 30 times the solar rotation) is almost negligible, being of the same order as gas diffusion and being capable of mixing efficiently not more than the innermost 20 per cent of the stellar mass; for the solar angular velocity the effect is 1000 times smaller, thus practically nil. Eddington's suggestion that rotational currents are capable of maintaining uniform chemical composition in the radiative equilibrium layers of a star must be definitely rejected except for configurations on the verge of disruption by rotation.