An Investigation of the thermally induced flow oscillations in a forced flow boiling of nitrogen at high pressures

The results of experimental investigation of hydrodynamic instability of the forced flow of nitrogen, belling in a channel, are shown at not high mass flow rate of the heat-carrier. In experiments were used a round channel of diameter 11,9 mm and length 1447 mm. The pressure in experience changes from 2,6 to 13,6 bar, mass flow rate - from 100 to similar to 600 kg / (m(2)s). The influence on origin of hydrodynamic instability (thermal oscillations) mass flow rate of the heat-carrier, heat flux and length of a channel is investigated. Tn particular, is shown, that the increase of the mass flow. rare stabilizes flow in a channel of a forced flow boiling of nitrogen, increase of a heat flux on the contrary, destabilizes it. The change of relative length of a channel in range from l/d = 121.6 and to l/d = 185 practically does not render influence on value of a heat flux, at which there are oscillations in a boiling flow. The chart of stability for flow in a channel of a boiling nitrogen stream for a channel with relative length l/d = 121,6 for pressure p = 2,6 divided by 13,6 bar is offered.