A Heuristic Evaluation of the Governing Mode of Heat Transfer in a Liquid–Liquid Spray Column

Jacobs, Hans; Golafshani, Mehdi

doi:10.1115/1.3250750

Cited by 19 publications

(7 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This can be made reasonably acceptable by means of a constant holdup ratio along the column height, which has been demonstrated for the direct contact evaporator [27][28][29]. -The heat losses from the direct contact column to the environment are ignored.…”

Section: Resultsmentioning

confidence: 97%

Experimental measurements and theoretical prediction for the volumetric heat transfer coefficient of a three-phase direct contact condenser

Mahood

Campbell

Thorpe

et al. 2015

International Communications in Heat and Mass Transfer

View full text Add to dashboard Cite

Section: Resultsmentioning

confidence: 97%

Experimental measurements and theoretical prediction for the volumetric heat transfer coefficient of a three-phase direct contact condenser

Mahood

Campbell

Thorpe

et al. 2015

International Communications in Heat and Mass Transfer

View full text Add to dashboard Cite

“…• Both continuous phase and dispersed phase mass flow rates are assumed constant along the column. This can be made reasonably acceptable by means of a constant holdup ratio along the column height which has been demonstrated for both direct contact evaporator [22][23][24] and direct contact condenser [17,18]. • The heat losses from the direct contact column to the environment are ignored.…”

Section: Resultsmentioning

confidence: 97%

Transient volumetric heat transfer coefficient prediction of a three-phase direct contact condenser

2014

View full text Add to dashboard Cite

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. List of symbolsA Cross-section area (m 2 ) C pc Specific heat of continuous phase (kJ/kg°C) hfg Latent heat of condensation (kJ/kg) _ m Mass flow rate (kg/s) Q Heat transfer rate (kW) t Time (s) T Temperature (°C) u Velocity (m/s) V Column volume (m 3 ) Z Axial height (m)Greek symbols q Density (kg/m 3 ) D Difference (-)

show abstract

“…Initially, due to the large diameter of the column in comparison to the diameter of the drops, and because there is no circulation zone inside the column, the flow inside the column can be assumed to be a one-dimensional flow [9]. On the other hand, immiscibility between the countercurrent flow phases means the mass flow rate of both phases stays constant along the column because neither the dispersed phase or the continuous phasen goes into solution in the other phase.…”

Section: Theoretical Modellingmentioning

confidence: 99%

“…The volumetric heat transfer coefficient was found and they correlated their experimental results of volumetric heat transfer as a function of holdup ratio. By using a numerical technique Coban and Boehm [8], Jacobs and Golafshani [9] and Brickman and Boehm [10] developed a one-dimensional numerical model to study the flow and the heat transfer of a spray column direct contact heat exchanger. The mass, momentum, and energy equations of two-component two-phase flow were solved and the temperature profile, total heat transfer, and holdup ratio were calculated.…”

Section: Introductionmentioning

confidence: 99%

“…The mass, momentum, and energy equations of two-component two-phase flow were solved and the temperature profile, total heat transfer, and holdup ratio were calculated. Several heat transfer models for interfacial heat transfer between the dispersed and continuous phases were examined by [9] and they found that the conduction controlled heat transfer is dominated by small diameter liquid drops. While, the possibility of increasing a spray column direct contact heat transfer output was included in the analysis of Brickman and Boehm [10].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Analytical Modelling of a Spray Column Three-Phase Direct Contact Heat Exchanger

Mahood

Sharif

Hosseini

et al. 2013

ISRN Chemical Engineering

View full text Add to dashboard Cite

An analytical model for the temperature distribution of a spray column, three-phase direct contact heat exchanger is developed. So far there were only numerical models available for this process; however to understand the dynamic behaviour of these systems, characteristic models are required. In this work, using cell model configuration and irrotational potential flow approximation characteristic models has been developed for the relative velocity and the drag coefficient of the evaporation swarm of drops in an immiscible liquid, using a convective heat transfer coefficient of those drops included the drop interaction effect, which derived by authors already. Moreover, one-dimensional energy equation was formulated involving the direct contact heat transfer coefficient, the holdup ratio, the drop radius, the relative velocity, and the physical phases properties. In addition, time-dependent drops sizes were taken into account as a function of vaporization ratio inside the drops, while a constant holdup ratio along the column was assumed. Furthermore, the model correlated well against experimental data.

show abstract

A Heuristic Evaluation of the Governing Mode of Heat Transfer in a Liquid–Liquid Spray Column

Cited by 19 publications

References 0 publications

Experimental measurements and theoretical prediction for the volumetric heat transfer coefficient of a three-phase direct contact condenser

Experimental measurements and theoretical prediction for the volumetric heat transfer coefficient of a three-phase direct contact condenser

Transient volumetric heat transfer coefficient prediction of a three-phase direct contact condenser

Analytical Modelling of a Spray Column Three-Phase Direct Contact Heat Exchanger

Contact Info

Product

Resources

About