Heat rectangular channel

Kast, W., 1964, Significance of Nucleating and Non-stationary Heat Transfer in the Heat Exchanger during Bubble Vaporization and Droplet Condensation, Chem. Eng. Tech. 36(9) 933-940. (2) Katto, Y., 1981, General Features of CHF of Forced Convection Boiling in Uniformly Heated Rectangular Channels, Ini. J. Heat Mass Transfer 24.14131419. (5)... 

Katto Y (1981) General features of CHF of forced convection boiling in uniformly heated rectangular channels. Int J Heat Mass Transf 24 1413-1419... 

The rectangular channels tested have three characteristic dimensions the flow width (which measures 1 in. for all the data shown in Table III), an equivalent heated width (which measures approximately 0.9 in.), and the internal spacing S between the flat heating surfaces. The heated width and the flow width are not the same, due to the way the channels are constructed,... 

Range of System Parameters for Burn-Out in Rectangular Channels Uniformly Heated (Lengthwise) with Liquid Water Inlet ... 

D2. De Bortoli, R. A., Green, S. J., Le Tourneau, B. W., Troy, M., and Weiss, A., Forced convection heat transfer burnout studies for water in rectangular channels and round tubes at pressure above 500 psia, WAPD-188 (1958). 

J6. Jiji, L. M Incipient boiling and the bubble boundary layer formation over a heated plate for forced convection flow in a pressurized rectangular channel, Ph.D. Thesis, Univ. of Michigan, Ann Arbor, 1962. 

M3. Macbeth, R. V., Burnout analysis. 4. Application of a local conditions hypothesis to world data for uniformly heated round tubes and rectangular channels, AEEW-R.267 (1963). 

The heat transfer and pressure drop in a rectangular channel with sintered porous inserts, made of stainless steels of different porosity, were investigated. The experimental set-up is shown in Fig. 2.9. Heat fluxes up to 6MW/m were removed by using samples with a porosity of 32% and an average pore diameter of 20 pm. Under these experimental conditions, the temperature difference between the wall and the bulk water did not exceed AT = 55 K at a pressure drop of AP = 4.5 bars (Hetsroni et al. 2006a). 

Figure 2.48 compares the predictions of this correlation with the flow boiling CHF data for water both in the rectangular micro-channel heat sink (Qu and Mudawar 2004) and in the circular mini/micro-channel heat sinks (Bowers and Mudawar 1994). The overall mean absolute error of 4% demonstrates its predictive capability for different fluids, circumferential heating conditions, channel geometries, channel sizes, and length-to-diameter ratios. 

Warrier et al. (2002) conducted experiments of forced convection in small rectangular channels using FC-84 as the test fluid. The test section consisted of five parallel channels with hydraulic diameter = 0.75 mm and length-to-diameter ratio Lh/r/h = 433.5 (Fig. 4.5d and Table 4.4). The experiments were performed with uniform heat fluxes applied to the top and bottom surfaces. The wall heat flux was calculated using the total surface area of the flow channels. Variation of single-phase Nusselt number with dimensionless axial distance is shown in Fig. 4.6b. The numerical results presented by Kays and Crawford (1993) are also shown in Fig. 4.6b. The measured values agree quite well with the numerical results. 

The thermal balance equation for rectangular channels with four or three heated walls shown in Fig. 6.10 are ... 

Fig. 6.10 Rectangular channels (a) four heated walls, (b) three heated walls...

If the value of rB,oNB Ts, (D -c 1) the integral characteristics for the circular channels, the rectangular channels with four and three heated walls, respectively,... 

The heat transfer coefficient of boiling flow through a horizontal rectangular channel with low aspect ratio (0.02-0.1) was studied by Lee and Lee (2001b). The mass flux in these experiments ranged from 50 to 200 kg/m s, maximum heat flux was 15 kW/m, and the quality ranged from 0.15 to 0.75, which corresponds to annular flow. The experimental data showed that under conditions of the given experiment, forced convection plays a dominant role. 

Shuai J, Kulenovic R, DroU M (2003) Heat transfer and pressure drop for flow boiling of water in narrow vertical rectangular channels. In Proceedings for 1st International Conference on Micro-channels, Rochester, New York, 24-25 April 2003, ICMM 2003-1084 Staniszewski BE (1959) Nucleate boihng bubble growth and departure MIT DSR Project N7-7673, Technical Report N16... 

Tran TN, Wambsganss MW, France DM (1996) Small circular and rectangular channel boiling with two refrigerants. Int J Multiphase Flow 22 485-498 Unal HC (1975) Determination of the initial point of net vapor generation in flow boiling system. Int J Heat Mass Transfer 18 1095-1099... 

Landerman (1994) developed an analytical model for two-phase boiling heat transfer in a high aspect ratio rectangular channel. The flow regimes in the channel were mapped and then the heat transfer and wall temperature were evaluated, using heat transfer coefficients taken from the literature. 

Effectively, Eqs. (86) and (87) describe two interpenetrating continua which are thermally coupled. The value of the heat transfer coefficient a depends on the specific shape of the channels considered suitable correlations have been determined for circular or for rectangular channels [100]. In general, the temperature fields obtained from Eqs. (86) and (87) for the solid and the fluid phases are different, in contrast to the assumptions made in most other models for heat transfer in porous media [117]. Kim et al. [118] have used a model similar to that described here to compute the temperature distribution in a micro channel heat sink. They considered various values of the channel width (expressed in dimensionless form as the Darcy number) and various ratios of the solid and fluid thermal conductivity and determined the regimes where major deviations of the fluid temperature from the solid temperature are found. 

The CHF in vertical upward and downward, countercurrent flow was recently studied by Sudo et al. (1991) in a vertical rectangular channel. Sudo and Kaminaga (1993) later presented a new CHF correlation scheme for vertical rectangular channels heated from both sides in a nuclear research reactor. 

Cheng, L. Y., andP. R.Tichler, 1991, CHF for Free Convection Boiling in Their Rectangular Channels, ANS Proc. Natl. Heat Transfer Conf., Minneapolis, MN, pp. 83-90. (2)... 

DeBortoli, R. A., S. J. Green, B. W. LeTourneau, M. Troy, and A. Weiss, 1958, Forced Convection Heat Transfer Burnout Studies for Water in Rectangular Channels and Round Tubes at Pressures above 500 psia, USAEC Rep. WAPD-188, Pittsburgh, PA. (5)... 

Ivey, H. J., and D. J. Morris, 1965, The Effect of Test Section Parameters on Saturation Pool Boiling Burnout at Atmospheric Pressure, AIChE Chem. Eng. Prog. Symp. Ser. 67(60) 157—166. (2) Jacket, H. S., J. D. Roarty, and J. E. Zerbe, 1958, Investigation of Burnout Heat Flux in Rectangular Channels at 2000 psia, Trans. ASME, J. Heat Transfer 50 391. (5)... 

Macbeth, R. V., 1963a, Burnout Analysis Pt. 2, The Basic Burnout Curve, UK Rep. AEEW-R-167 Pt. 3, The Low Velocity Burnout Regime, AEEW-R-222 Pt. 4, Application of Local Conditions Hypothesis to World Data for Uniformly Heated Round Tubes and Rectangular Channels, AEEW-R-267, UK AEEW, Winfrith, England. (5)... 

Monde, M., H. Kusuda, and H. Uehara, 1982, Critical Heat Flux during Natural Convective Boiling in Vertical Rectangular Channels Submerged in Saturated Liquid, Trans. ASME, J. Heal Transfer 704 300-303. (5)... 

Sudo, Y., M. Kaminaga, 1993, A New CHF Correlation Scheme Proposed for Vertical Rectangular Channels Heated from Both Sides in Nuclear Reactors, Trans. ASME, J. Heat Transfer 115 426-434.(5)... 

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