Flow boiling heat transfer in a single small tube is investigated by using FC72 as a working fluid. The heat transfer coefficients are measured in the ranges of heat flux 2–24kW/m2 and mass velocity 100–400kg/m2s under the condition of near atmospheric pressure. Test tube, made of stainless steel, has an inner diameter of 0.51mm and a heated length of 200mm. The tube is located horizontally in a vacuum chamber to reduce the heat loss and to minimize the time to obtain data regarded as that of steady state. In the single-phase region, heat transfer coefficients due to forced convection are in good agreement with the values from the conventional theories. In the saturated region, measured heat transfer characteristics are quite different depending on whether the test liquid is deaerated or not deaerated before the experiments. By using deaerated liquid, three different heat transfer regimes are observed: In the first regime, the heat transfer is dominated by nucleate boiling in low vapor quality, and the heat transfer is deteriorated or enhanced depending on the channel confinement and heat flux. In the second regime, the heat transfer is dominated by two-phase forced convection in moderate quality as is well known for the tubes of normal size. In the third regime, the heat transfer is dominated again by two-phase forced convection, but is deteriorated in high quality. One or two regimes can disappear or become unclear depending on the conditions of flow and heating. The effects of vapor quality and mass velocity on the heat transfer characteristics due to two-phase forced convection in the moderate vapor quality are clarified in the experimental ranges tested. And a reason for the gradual heat transfer deterioration observed in high quality is discussed based on the liquid-vapor behaviors inherent in small diameter tubes.
Skip Nav Destination
ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels
June 19–21, 2006
Limerick, Ireland
Conference Sponsors:
- Nanotechnology Institute
ISBN:
0-7918-4760-8
PROCEEDINGS PAPER
Experimental Study on Flow Boiling Heat Transfer in an Extremely Small Tube Available to Purchase
Haruhiko Ohta,
Haruhiko Ohta
Kyushu University, Fukuoka, Japan
Search for other works by this author on:
Koichi Inoue,
Koichi Inoue
Kyushu University, Fukuoka, Japan
Search for other works by this author on:
Yuichiro Shimada
Yuichiro Shimada
Kyushu University, Fukuoka, Japan
Search for other works by this author on:
Haruhiko Ohta
Kyushu University, Fukuoka, Japan
Koichi Inoue
Kyushu University, Fukuoka, Japan
Yuichiro Shimada
Kyushu University, Fukuoka, Japan
Paper No:
ICNMM2006-96177, pp. 105-113; 9 pages
Published Online:
September 15, 2008
Citation
Ohta, H, Inoue, K, & Shimada, Y. "Experimental Study on Flow Boiling Heat Transfer in an Extremely Small Tube." Proceedings of the ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels. ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels, Parts A and B. Limerick, Ireland. June 19–21, 2006. pp. 105-113. ASME. https://doi.org/10.1115/ICNMM2006-96177
Download citation file:
8
Views
Related Proceedings Papers
Related Articles
Impact of Weather Conditions Variability on External Receivers in Real-World Direct Steam Generation Solar Power Tower Plants
J. Thermal Sci. Eng. Appl (January,0001)
Steady-State Subcooled Nucleate Boiling on a Downward-Facing Hemispherical Surface
J. Heat Transfer (May,1998)
Flow Visualization and Local Measurement of Forced Convection Heat Transfer in a Microtube
J. Heat Transfer (March,2010)
Related Chapters
Constraints
Nonlinear Regression Modeling for Engineering Applications: Modeling, Model Validation, and Enabling Design of Experiments
Energy Balance for a Swimming Pool
Electromagnetic Waves and Heat Transfer: Sensitivites to Governing Variables in Everyday Life
How to Use this Book
Thermal Spreading and Contact Resistance: Fundamentals and Applications