FORCED CONVECTIVE SUBCOOLED BOILING HEAT TRANSFER AND CHF IN SMALL-DIAMETER TUBES

1990 ◽  
Author(s):  
S. Hosaka ◽  
Masaru Hirata ◽  
Nobuhide Kasagi
Keyword(s):  
Heat Transfer ◽  
Boiling Heat Transfer ◽  
Small Diameter ◽  
Subcooled Boiling

scholarly journals Prediction for Flow Boiling Heat Transfer in Small Diameter Tube Using Deep Learning

2017 ◽  
Vol 31 (4) ◽  
pp. 412-421 ◽  
Author(s):  
Koji ENOKI ◽  
Yuichi SEI ◽  
Tomio OKAWA ◽  
Kiyoshi SAITO
Keyword(s):  
Heat Transfer ◽  
Deep Learning ◽  
Boiling Heat Transfer ◽  
Flow Boiling ◽  
Small Diameter ◽  
Flow Boiling Heat Transfer

Subcooled Water Flow Boiling Heat Transfer in a Short SUS304-Tube With Twisted-Tape Insert

2010 ◽  
Author(s):  
Koichi Hata ◽  
Suguru Masuzaki
Keyword(s):  
Heat Transfer ◽  
Boiling Heat Transfer ◽  
Flow Boiling ◽  
Test Tube ◽  
Heat Fluxes ◽  
Effective Length ◽  
Twisted Tape ◽  
Subcooled Boiling ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients

The subcooled boiling heat transfer (HT) and the steady-state critical heat fluxes (CHFs) in a short SUS304-tube with twisted-tape insert are systematically measured for mass velocities (G = 4016 to 13850 kg/m2s), inlet liquid temperatures (Tin = 285.82 to 363.96 K), outlet pressures (Pout = 764.76 to 889.02 kPa) and exponentially increasing heat input (Q = Q0exp(t/τ), τ = 8.5 s) by the experimental water loop comprised of a multistage canned-type circulation pump controlled by an inverter. The SUS304 test tube of inner diameter (d = 6 mm), heated length (L = 59.5 mm), effective length (Leff = 49.1 mm), L/d (= 9.92), Leff/d (= 8.18) and wall thickness (δ = 0.5 mm) with average surface roughness (Ra = 3.18 μm) is used in this work. The SUS304 twisted tape with twist ratio, y [= H/d = (pitch of 180° rotation)/d], of 3.39 is used. The relation between inner surface temperature and heat flux for the SUS304-tube with the twisted-tape insert are clarified from non-boiling to CHF. The subcooled boiling heat transfer for SUS304-tube with the twisted-tape insert is compared with our empty SUS304-tube data and the values calculated by our and other workers’ correlations for the subcooled boiling heat transfer. The influences of the twisted-tape insert and the swirl velocity on the subcooled boiling heat transfer and the CHFs are investigated into details and the widely and precisely predictable correlations of the subcooled boiling heat transfer and the CHFs for turbulent flow of water in the SUS304-tube with twisted-tape insert are given based on the experimental data. The correlations can describe the subcooled boiling heat transfer coefficients and the CHFs obtained in this work within −25 to +15% difference.

Subcooled Boiling Heat Transfer for Turbulent Flow of Water in a Short Vertical Tube

2009 ◽  
Vol 132 (1) ◽  
Author(s):  
Koichi Hata ◽  
Suguru Masuzaki
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Turbulent Flow ◽  
Critical Heat Flux ◽  
Boiling Heat Transfer ◽  
Vertical Tube ◽  
Test Tube ◽  
Subcooled Boiling ◽  
Transfer Coefficients ◽  
Infrared Thermal Imaging

The subcooled boiling heat transfer and the critical heat flux (CHF) due to exponentially increasing heat inputs with various periods (Q=Q0 exp(t/τ), τ=22.52 ms–26.31 s) were systematically measured by an experimental water loop flow and observed by an infrared thermal imaging camera. Measurements were made on a 3 mm inner diameter, a 66.5 mm heated length, and a 0.5 mm thickness of platinum test tube, which was divided into three sections (upper, mid, and lower positions). The axial variations of the inner surface temperature, the heat flux, and the heat transfer coefficient from nonboiling to critical heat flux were clarified. The results were compared with other correlations for the subcooled boiling heat transfer and authors’ transient CHF correlations. The influence of exponential period (τ) and flow velocity on the subcooled boiling heat transfer and the CHF was investigated and the predictable correlation of the subcooled boiling heat transfer for turbulent flow of water in a short vertical tube was derived based on the experimental data. In this work, the correlation gave 15% difference for subcooled boiling heat transfer coefficients. Most of the CHF data (101 points) were within 15% and −30 to +20% differences of the authors’ transient CHF correlations against inlet and outlet subcoolings, respectively.

scholarly journals Boiling heat transfer of refrigerant R-113 in a small-diameter, horizontal tube

1992 ◽  
Author(s):  
M.W. Wambsganss ◽  
J.A. Jendrzejczyk ◽  
T.N. Tran ◽  
D.M. France
Keyword(s):  
Heat Transfer ◽  
Boiling Heat Transfer ◽  
Small Diameter ◽  
Horizontal Tube
Sign in / Sign up

Export Citation Format

Share Document