Convective vaporization in micro-fin tubes of different geometries
(2013) In Experimental Thermal and Fluid Science 44. p.398-408- Abstract
- An experimental investigation was performed for convective vaporization of R22 and R410A inside one smooth tube and five micro-fin tubes with the same outer diameter of 5 mm. Data are for mass fluxes ranging from 100 to 620 kg/m2 s at 279 K saturation temperature. The results suggest that the tube with fin height of 0.15 mm, apex angle of 25° and 38° starts has the best thermal performance for convective vaporization when mass velocity is less than 400 kg/m2 s, while the tube with fin height of 0.12 mm, apex angle of 25° and 58° starts has the best heat transfer performance at larger mass velocities, which is probably due to the relative size between fin height and liquid film thickness. Considering the effects of micro-fin on flow... (More)
- An experimental investigation was performed for convective vaporization of R22 and R410A inside one smooth tube and five micro-fin tubes with the same outer diameter of 5 mm. Data are for mass fluxes ranging from 100 to 620 kg/m2 s at 279 K saturation temperature. The results suggest that the tube with fin height of 0.15 mm, apex angle of 25° and 38° starts has the best thermal performance for convective vaporization when mass velocity is less than 400 kg/m2 s, while the tube with fin height of 0.12 mm, apex angle of 25° and 58° starts has the best heat transfer performance at larger mass velocities, which is probably due to the relative size between fin height and liquid film thickness. Considering the effects of micro-fin on flow boiling, a new general semi-empirical model has been developed based on the present data and recent data from literature. The new model is applicable for intermittent and annular flow patterns, covering different fluids, nominal diameters from 2.1 to 14.8 mm, mass fluxes from 100 to 650 kg/m2 s, heat fluxes based on the total inner surface area from 0 to 30 kW/m2, and reduced pressure from 0.08 to 0.69. The model predicts the parametric trends correctly and the average and local heat transfer coefficients accurately. The heat transfer mechanism can also be observed clearly by the new model. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/4285356
- author
- Wu, Zan LU ; Wu, Yang ; Sundén, Bengt LU and Li, Wei
- organization
- publishing date
- 2013
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Pressure drop, Heat transfer, Micro-fin tube, Convective vaporization
- in
- Experimental Thermal and Fluid Science
- volume
- 44
- pages
- 398 - 408
- publisher
- Elsevier
- external identifiers
-
- wos:000316515400040
- scopus:84869184312
- ISSN
- 1879-2286
- DOI
- 10.1016/j.expthermflusci.2012.07.012
- language
- English
- LU publication?
- yes
- id
- 8bf2494c-a0e2-42c2-96cb-e2c426d8cd96 (old id 4285356)
- date added to LUP
- 2016-04-04 08:01:14
- date last changed
- 2022-04-23 17:00:16
@article{8bf2494c-a0e2-42c2-96cb-e2c426d8cd96,
abstract = {{An experimental investigation was performed for convective vaporization of R22 and R410A inside one smooth tube and five micro-fin tubes with the same outer diameter of 5 mm. Data are for mass fluxes ranging from 100 to 620 kg/m2 s at 279 K saturation temperature. The results suggest that the tube with fin height of 0.15 mm, apex angle of 25° and 38° starts has the best thermal performance for convective vaporization when mass velocity is less than 400 kg/m2 s, while the tube with fin height of 0.12 mm, apex angle of 25° and 58° starts has the best heat transfer performance at larger mass velocities, which is probably due to the relative size between fin height and liquid film thickness. Considering the effects of micro-fin on flow boiling, a new general semi-empirical model has been developed based on the present data and recent data from literature. The new model is applicable for intermittent and annular flow patterns, covering different fluids, nominal diameters from 2.1 to 14.8 mm, mass fluxes from 100 to 650 kg/m2 s, heat fluxes based on the total inner surface area from 0 to 30 kW/m2, and reduced pressure from 0.08 to 0.69. The model predicts the parametric trends correctly and the average and local heat transfer coefficients accurately. The heat transfer mechanism can also be observed clearly by the new model.}},
author = {{Wu, Zan and Wu, Yang and Sundén, Bengt and Li, Wei}},
issn = {{1879-2286}},
keywords = {{Pressure drop; Heat transfer; Micro-fin tube; Convective vaporization}},
language = {{eng}},
pages = {{398--408}},
publisher = {{Elsevier}},
series = {{Experimental Thermal and Fluid Science}},
title = {{Convective vaporization in micro-fin tubes of different geometries}},
url = {{http://dx.doi.org/10.1016/j.expthermflusci.2012.07.012}},
doi = {{10.1016/j.expthermflusci.2012.07.012}},
volume = {{44}},
year = {{2013}},
}