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Cavitation occurs in a wide range of applications, such as in marine propellers, diesel injectors, supercavitating projectiles, etc. Currently, the available cavitation models rely on expressions derived from inertial bubble growth models and fine-tuned using a few experiments. Revisiting the literature on bubble growth models indicates that there is scope for improvement in the bubble growth expressions presently employed. The previous studies in this subject have assumed that the vapor in the bubble remains saturated. Detailed numerical studies using one-dimensional saturated vapor model reveals over-prediction of the bubble radius when compared with a wide range of experimental data. To overcome this, a coupled mass, momentum, and energy model, termed full model, is then developed and the analysis suggests that this model gives good agreement over the entire experimental data. Parametric studies carried out to generate non-dimensional bubble growth rate expressions indicate that the growth rate climbs linearly on a log –log plot during initial stages of bubble growth which is function Jakob number J a and finally settles into an asymptotic non-linear curve which is independent of J a. The bubble growth rate expressions when integrated to obtain bubble radius as function of time is able to predict the experimental data with mean relative error of 1.2% and root mean square relative error of 8% for J a varying from 13.53 to 2745.

To predict nucleate boiling, a novel semimechanistic wall boiling model is developed within a mixture multiphase flow framework available in ansys fluent. The mass transfer phenomenon is modeled using an evaporation–condensation model, and enhancement of wall-to-fluid heat transfer due to nucleate boiling is captured using a 1D empirical correlation, modified for 3D computational fluid dynamics (CFD) environment; hence this model can be used for a complex-shaped coolant passage. For a series of operating conditions, the present model is rigorously validated against available experimental data in which a 50% volume mixture of aqueous ethylene glycol was used as coolant. Subsequently, this model is applied to study boiling heat transfer for a typical automobile exhaust gas recirculation (EGR) cooler under a typical condition.

The growing awareness of pollutant emissions from gas turbines has made it very important to study fuel atomization system, the spray wall interaction and hydrodynamic of film formed on engine walls. A precise fuel spray spatial distribution and efficient fuel air mixing plays important role in improving combustion performance. Cross-flow injection and film atomization technique has been studied extensively for gas turbine engines to achieve efficient combustion. Air blast atomizer is one of these kind of systems used in gas turbine engines which involves shear driven prefilmer secondary atomization. In addition to gas turbine combustor shear driven liquid wall film can be seen in IC engines, rocket nozzles, heat exchangers and also on steam turbine blades. In our work we have used Eulerian Wall Film (EWF) [1] model to simulate the experiment performed by Arienti et al. [2]. In the Arienti’s experiment liquid jet is injected from a nozzle from the top of the chamber. Droplets shed from the jet surface due to primary and later secondary atomization in the presence of high shearing cross flowing air. Further liquid fuel particles hit the wall to form film, film moves subjected to shear from the gas phase. Liquid film can reatomizes due to subgrid processes like stripping, splashing and film breakup. In current study we have validated Arienti et al. [2] experimental data by modeling complex & coupled physics of spray, film and continuous phase and by accounting complex subgrid processes.