Publication de 6 numéros par an
ISSN Imprimer: 1948-2590
ISSN En ligne: 1948-2604
KINEMATIC FOUNDATIONS OF THE RANQUE EFFECT MECHANISMHEAT SEPARATION OF FLUID AND GAS FLOW IN A VORTEX TUBE
RÉSUMÉ
The known effect of gas flow heat separation discovered by Ranque [1] is still not properly explained by science. The experimental fact of such separation is also known for fluid in nominal Ranque tubes [2]. Flow heat separation was numerically simulated on the example of laminar self-similar whirled flows in expanding cone-like channels, channels had an injection vector oriented along the porous wall. The mechanism of the process, which has a kinematic basis, is brought to light. The kinematic factor that is exhibited by intense flow swirl conditions stipulates higher inner supply of viscous dissipation heat of fluid kinetic energy compared to its absence (by means of an increased radial speed gradient near the wall in its essence). The implemented mathematical model allowed reconstructing qualitatively the non-monotonic character of excess temperature t − tw alteration in the cross section of the channel with cooled walls and heat outflow of the channel, and also its negative values near the real Ranque tube axis [2]. The realized t − tw values are conditioned by the recurrent character of transition lines (via convection and thermal conductivity) of heat in the meridional section of the cone channel, those lines coincide at a specific point r = 0 from where they start. The results of the self-similar heat task solution also prove the non-monotonic profile of excess temperature and recurrence of transition lines in the case of flat cone-type fluid flow (Hamel flow in flat extending channels). The specific case of stagnation temperature stratification along the channel section in a cone-like whirled flow of viscous gas is discussed.