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Gas-liquid jet reactors are widely used in commercial applications such as condensing jets for direct contact feedwater heaters and steam jet pumps, because of their efficient heat-and mass-transfer characteristics. These are also used for the blowdown of primary nuclear boiler systems into a water bath, without releasing fissionable materials into the atmosphere. Reacting jets are of major interest in metal processing and thermal energy sources that involve submerged injection of an oxidizer into a liquid metal bath. The design of gasliquid jet reactors is strongly dependent on the plume dimensions and the flow pattern in the liquid phase. In the present review paper, a critical analysis of the published literature on the fluid dynamics and heat transfer for gas-liquid jet reactors has been performed. The analysis has been extended for the empirical, semiempirical, and analytical attempts for the correlations of experimental observations. The published works on the computational fluid dynamics (CFD) simulations have also been critically analyzed. A comprehensive discussion has been presented and an attempt has been made to arrive at a coherent theme that clearly describes the present status of the published literature. Furthermore, recommendations have been made that are expected to be useful for the design engineers as well as researchers, to improve the reliability in the design of this important class of reactors.

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High frequency experimental measurements by hot film anemometry (HFA) of liquid velocities and temperature in the region of vapor-liquid (VL) and solid-liquid (SL) interfaces for two important reactor types, namely, condensation jet and jet loop reactors, have been studied for their heat transfer characteristics. An algorithm for flow structure identification has been devised from velocity data based on (i) zero crossings and (ii) continuous wavelet transform. The wavelet transform algorithm is especially found to be useful in accurately estimating both the age and size distributions of eddies near interfaces in a multiscale framework. Using these distributions, it is shown that the calculated values of heat transfer coefficients (HTC) at the SL and VL interfaces show remarkable correspondence with the HTC values obtained experimentally from instantaneous temperature measurements. For this purpose, a modified capacitance model has been proposed that takes into account the information about both the age and size distributions. The results obtained by the present methodology show the improvement possible for calculating the HTC at interfaces when compared with the earlier surface renewal models. It may therefore be used to study the interaction between flow dynamics and heat transfer behavior in chemical process equipment.