Numerical study of the effect of tube wall on subcooled boiling at the end of a laser waveguide

Results of numerical simulations of the laser-induced boiling at the end of waveguide placed inside the tube are presented. The effect of tube wall on the vapor bubble evolution and characteristics of the cumulative jet forming as a result of its collapse has been studied. Particularly, it is found that while the tubes of large radii insignificantly affect the velocity of the cumulative liquid jet, in the relatively narrow tubes the jet may not form at all. Effect of the tubes of moderate radii comes down to the decrease of the jet velocity compared with the case without the tube. Possible physical explanation of such influence of tube walls is proposed. Numerical results on laser-induced boiling inside the tubes are summarized in the regime diagram in the tube radius - waveguide radius plane.