Optimal selection of two-phase tube-side heat transfer model for small-scale LNG spiral wound heat exchanger

Small-scale devices of liquefied natural gas (LNG) have been widely applied in the natural gas industries, especially for stranded gas production. As the key equipment of LNG plants, the performance of the spiral wound heat exchanger (SWHE) influences operating costs, reliability and safety of the whole system. In order to obtain the accurate two-phase tube-side heat transfer model for small-scale LNG SWHE and analyze its thermal performance, an experimental device of dual mixed refrigeration (DMR) is constructed. A multi-phase multi- -stream calculation code for SWHE is developed to solve the energy balance equations among tube-side feed gas, tube-side refrigerant and shell-side refrigerant, based on experimental results and thermal property calculation. The results show that the homogeneous flow model can be applied to two-phase tube-side heat transfer calculation of feed gas and Bell and Ghaly?s model and Shah?s model can be both applied to the mixed refrigerant. The relative errors between the results of the experiment and program are all within the range of ?12%.

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Theoretical Post-Dryout Heat Transfer Model

International Journal of Computational Physics Series ◽

10.29167/a1i1p142-150 ◽

2018 ◽

Vol 1 (1) ◽

pp. 142-150

Author(s):

Murat Tunc ◽

Ayse Nur Esen ◽

Doruk Sen ◽

Ahmet Karakas

Keyword(s):

Heat Transfer ◽

Droplet Diameter ◽

Heat Transfer Model ◽

Transfer Model ◽

Operating Pressure ◽

Vertical Pipe ◽

Two Phase ◽

Experimental Values ◽

Reactor Operating ◽

Coolant System

A theoretical post-dryout heat transfer model is developed for two-phase dispersed flow, one-dimensional vertical pipe in a post-CHF regime. Because of the presence of average droplet diameter lower bound in a two-phase sparse flow. Droplet diameter is also calculated. Obtained results are compared with experimental values. Experimental data is used two-phase flow steam-water in VVER-1200, reactor coolant system, reactor operating pressure is 16.2 MPa. On heater rod surface, dryout was detected as a result of jumping increase of the heater rod surface temperature. Results obtained display lower droplet dimensions than the experimentally obtained values.

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A coupled heat transfer model of medium-depth downhole coaxial heat exchanger based on the piecewise analytical solution

Energy Conversion and Management ◽

10.1016/j.enconman.2019.112308 ◽

2020 ◽

Vol 204 ◽

pp. 112308 ◽

Cited By ~ 3

Author(s):

Ling Ma ◽

Yazhou Zhao ◽

Hongmei Yin ◽

Jun Zhao ◽

Wenjia Li ◽

...

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Analytical Solution ◽

Heat Transfer Model ◽

Transfer Model ◽

Coupled Heat Transfer

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Study on the Coupled Heat Transfer Model Based on Groundwater Advection and Axial Heat Conduction for the Double U-Tube Vertical Borehole Heat Exchanger

Sustainability ◽

10.3390/su12187345 ◽

2020 ◽

Vol 12 (18) ◽

pp. 7345

Author(s):

Linlin Zhang ◽

Zhonghua Shi ◽

Tianhao Yuan

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Heat Transfer Rate ◽

Flow Rate ◽

Transfer Rate ◽

Heat Transfer Model ◽

Transfer Model ◽

Borehole Heat Exchanger ◽

Coupled Heat Transfer ◽

Advection Velocity

In this paper, a dynamic heat transfer model for the vertical double U-tube borehole heat exchanger (BHE) was developed to comprehensively address the coupled heat transfer between the in-tube fluid and the soil with groundwater advection. A new concept of the heat transfer effectiveness was also proposed to evaluate the BHE heat exchange performance together with the index of the heat transfer rate. The moving finite line heat source model was selected for heat transfer outside the borehole and the steady-state model for inside the borehole. The data obtained in an on-site thermal response test were used to validate the physical model of the BHE. Then, the effects of soil type, groundwater advection velocity, inlet water flow rate, and temperature on the outlet water temperature of BHE were explored. Results show that ignoring the effects of groundwater advection in sand gravel may lead to deviation in the heat transfer rate of up to 38.9% of the ground loop design. The groundwater advection fosters the heat transfer of BHE. An increase in advection velocity may also help to shorten the time which takes the surrounding soil to reach a stable temperature. The mass flow rate of the inlet water to the BHE should be more than 0.5 kg·s−1 but should not exceed a certain upper limit under the practical engineering applications with common scale BHE. The efficiency of the heat transfer of the double U-tube BHE was determined jointly by factors such as the soil’s physical properties and the groundwater advection velocity.

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Performance study of a ground heat exchanger based on the multipole theory heat transfer model

Energy and Buildings ◽

10.1016/j.enbuild.2013.06.002 ◽

2013 ◽

Vol 65 ◽

pp. 231-241 ◽

Cited By ~ 32

Author(s):

Pingfang Hu ◽

Zhongyi Yu ◽

Na Zhu ◽

Fei Lei ◽

Xudong Yuan

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Heat Transfer Model ◽

Transfer Model ◽

Ground Heat Exchanger ◽

Performance Study

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Condensation in Horizontal Smooth Tubes: A New Heat Transfer Model for Heat Exchanger Design

Heat Transfer Engineering ◽

10.1080/01457630600793970 ◽

2006 ◽

Vol 27 (8) ◽

pp. 31-38 ◽

Cited By ~ 243

Author(s):

Alberto Cavallini ◽

Davide Del Col ◽

Luca Doretti ◽

Marko Matkovic ◽

Luisa Rossetto ◽

...

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Heat Transfer Model ◽

Transfer Model ◽

Heat Exchanger Design ◽

Smooth Tubes

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Flow Boiling in Horizontal Tubes: Part 3—Development of a New Heat Transfer Model Based on Flow Pattern

Journal of Heat Transfer ◽

10.1115/1.2830039 ◽

1998 ◽

Vol 120 (1) ◽

pp. 156-165 ◽

Cited By ~ 217

Author(s):

N. Kattan ◽

J. R. Thome ◽

D. Favrat

Keyword(s):

Heat Transfer ◽

Annular Flow ◽

Flow Boiling ◽

Heat Transfer Model ◽

Transfer Model ◽

Two Phase ◽

Horizontal Tubes ◽

High Vapor ◽

Coefficient Versus ◽

The Heat Transfer Coefficient

A new heat transfer model for intube flow boiling in horizontal plain tubes is proposed that incorporates the effects of local two-phase flow patterns, flow stratification, and partial dryout in annular flow. Significantly, the local peak in the heat transfer coefficient versus vapor quality can now be determined from the prediction of the location of onset of partial dryout in annular flow. The new method accurately predicts a large, new database of flow boiling data, and is particularly better than existing methods at high vapor qualities (x > 85 percent) and for stratified types of flows.

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