Experimental Investigation on Pressure Jump at Gas-Liquid Dumitrescu-Taylor Flow and at the Bubble Bottom

Abstract

In this work, we investigate an experimental study to measure the pressure jump and the axial pressure jump gradient at gas-liquid interface. The measures have been carried out along Dumitrescu-Taylor bubble length leading to gas-liquid interface. The difference of pressure between liquid and gas is very small and consequently its measurement is fastidious. To our knowledge, no experimental measurements on these two parameters have been reported previously. Interesting to access to this smallest pressure difference between liquid and gas, an experimental method has been implementing. We described this method for after to give measurements that can be used as quantitative prediction for such interfacial conditions on the modeling of the interfacial closure relations in two fluid models. The original results of recording signals show that the pressure jump depends on the distance with respect to the bubble nose and it increase with the bubble velocity. The same trend observed for the axial interfacial pressure jump gradient results. For fixed bubble, an order of magnitude of those last parameters is given. The experimental value of the pressure jump across the interface agrees very well with the calculated value from the Laplace’s capillary equation. This good agreement gives confidence in our measurements. Other measures are carried out to determine the pressure jump at the bottom of the bubble, which is compared to the calculated values.