A Heuristic Evaluation of the Governing Mode of Heat Transfer in a Liquid–Liquid Spray Column
01 Aug 1989-Journal of Heat Transfer-transactions of The Asme (American Society of Mechanical Engineers)-Vol. 111, Iss: 3, pp 773-779
TL;DR: In this article, a steady-state one-dimensional multiphase flow model is developed to describe the characteristics of a spray column type direct-contact liquid-liquid heat exchanger.
Abstract: A steady-state one-dimensional multiphase flow model is developed to describe the characteristics of a spray column type direct-contact liquid-liquid heat exchanger. Several models are assumed to describe the interphase heat exchange between water as the continuous phase and organic liquids as the dispersed phase. For small-diameter droplets, it is shown that existing experimental data are best described by a model that assumes the heat transfer is controlled by conduction within the drops
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TL;DR: In this paper, the average volumetric heat transfer coefficient in a spray column liquid-liquid-vapour direct contact evaporator has been experimentally investigated using a cylindrical Perspex tube of diameter 10 cm and height and 150 cm.
33 citations
TL;DR: In this article, an analytical form of the rectilinear equation of motion and energy equation of particles, droplets or bubbles has been developed for very low Reynolds and Peclet numbers.
27 citations
TL;DR: In this article, an investigation of dispersed liquid-liquid two-phase turbulent swirling flow in a horizontal pipe is conducted using a particle tracking velocimetry (PTV) technique and a shadow image technique (SIT).
Abstract: An investigation of dispersed liquid–liquid two-phase turbulent swirling flow in a horizontal pipe is conducted using a particle tracking velocimetry (PTV) technique and a shadow image technique (SIT). Silicone oil with a low specific gravity is used as immiscible droplets. A swirling motion is given to the main flow by an impeller installed in the pipe. Fluorescent tracer particles are applied to flow visualization. Red/green/blue components extracted from color images taken with a digital color CCD camera are used to simultaneously estimate the liquid and droplet velocity vectors. Under a relatively low swirl motion, a large number of droplets with low specific gravity tend to accumulate in the central region of the pipe. With increasing droplet volume fraction, the liquid turbulence intensity in the axial direction increases while that in the wall-normal direction decreases in the central region of the pipe. In addition, the turbulence modification in the present flow is strongly dependent on the droplet Reynolds number; however, the interaction of droplet-induced turbulences is significant due to vortex shedding, particularly at high droplet Reynolds numbers and higher droplet volume fraction.
25 citations
Cites background from "A Heuristic Evaluation of the Gover..."
...Jacobs and Golafshani (1989) studied the heat transfer characteristics of isobutane droplets in water....
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TL;DR: In this paper, the volumetric heat transfer coefficient of a three-phase direct contact heat transfer condenser has been investigated analytically and experimentally using a column of 70 cm in total height and 4 cm inner diameter.
22 citations
TL;DR: In this article, an experimental investigation for the time dependent volumetric heat transfer coefficient of the bubbles type, three-phase direct contact condenser has been carried out utilising a short column (70 cm in total height and 4 cm inner diameter).
Abstract: An experimental investigation for the time dependent volumetric heat transfer coefficient of the bubbles type, three-phase direct contact condenser has been carried out utilising a short column (70 cm in total height and 4 cm inner diameter). A 47 cm active height was chosen with five different mass flow rate ratios and three different initial dispersed phase temperatures. Vapour pentane and constant temperature tap water as dispersed and continuous phases were implemented. The results showed that the volumetric heat transfer coefficient decreases with increased time until it almost reaches its steady state conditions. A sharp decrease in the volumetric heat transfer coefficient was found at the beginning of the operation and, diminished over a short time interval. Furthermore, a positive effect of the mass flow rate ratios on the volumetric heat transfer coefficient was noted and this was more pronounced at the beginning of the operation. On the other hand, the volumetric heat transfer coefficient decreased with an increase in the continuous phase mass flow rate and there was no considerable effect of the initial dispersed phase temperatures, which confirms that latent heat transfer is dominant in the process.
22 citations