Modeling the Process of Heat Transfer from the Surface of Liquid Metals

The paper presents the dependences for the heat flux density q and the equivalent heat transfer coefficient
$\alpha$
during evaporation into vacuum and the vapor phase depending on the temperature of the coolant at the phase transition boundary. It was found that the calculated values of
$\alpha$
for lithium, sodium and potassium are
$\sim 10^{5}-10^{6}\mathrm{W}/(\mathrm{m}^{2}\mathrm{K})$
, which is in agreement with the experimental data. On the basis of the obtained relations for q, the process of heat transfer due to evaporation in the model of the shot through the anode of a microfocus X-ray tube was simulated. The simulation results showed that in the shot through the anode with sodium evaporation, the input power can be 100 W with a heat release region diameter of 100 μm.