Crossflow: heat transfer

ESDU 73031 (1973) Convective heat transfer during crossflow of fluids over plain tube banks. 

Figure 6.13 compares Eq. (6-26) with available numerical solutions and experimental data of Hilpert (FI, H4) for heat transfer to air. Agreement is good even for Re as high as 10. The review of Morgan (M12) should be consulted for additional data and discussion on transfer to cylinders in crossflow. 

The design calculations highlighted the shortcomings of the Kern method of exchanger design. The Kern method fails to account for shell-side inefficiencies such as bypassing, leakage, crossflow losses, and window losses. This leads to a marked overestimate of the shell-side heat-transfer coefficient and shell-side pressure drop. The Bell method is recommended to correct these deficiencies. 

Soc. Mech. Engrs. 74 (1952), 343-347 Distribution of heat transfer coefficients around circular cylindres in crossflow at Reynolds numbers from 20 to 500. 

Fand, R. M. Heat Transfer by Forced Convection from a Cylinder to Water in Crossflow, Int. J. Heat Mass Transfer, vol. 8, p. 995, 1965. 

Zukauskas, A. A., V. Makarevicius, and A. Schlanciauskas Heat Transfer in Banks of Tubes in Crossflow of Fluid, Mintis, Vilnius, Lithuania, 1968. 

Churchill, S. W., and M. Bernstein A Correlating Equation for Forced Convection from Gases and Liquids to a Circular Cylinder in Crossflow, J. Heat Transfer, vol. 99, pp. 300-306, 1977. 

Equations (45) and (46) are only two of many formulas that have been used to describe erosive burning [8]. Most of the formulas that have been suggested are based on physical concepts of influences of crossflow on propellant burning. Among these concepts is the idea that high external velocities produce a turbulent boundary layer (see Chapter 12) on the propellant surface and thereby effectively increase the thermal diffusivity of the gas, which in turn increases the rate of heat transfer to the propellant and hence the burning rate [99]. The idea that turbulent convective heat transfer from the hot combustion products outside the boundary layer provides an additive contribution to the heat flux reaching the propellant surface and,... 

Hansen, Heat Transfer in Counterflow, Parallelflow and Crossflow,... 

An increase in the number n of tube rows in series approaches the case of pure crossflow, in which the temperatures of both fluids change in x and y or rather the dimensionless coordinates x+ and y+, from (1.121), cf. Fig. 1.23. The heat transferred, through a surface element of dimensions... 

In the following, the heat transfer and pressure drop in a tube bundle in crossflow will be investigated. The individual tubes in the bundle are either in alignment with each other or in a staggered arrangement, according to Fig. 3.25. 

The flow around and therefore the heat transfer around an individual tube within the bundle is influenced by the detachment of the boundary layer and the vortices from the previous tubes. The heat transfer on a tube in the first row is roughly the same as that on a single cylinder with a fluid in crossflow, provided the transverse pitch between the tubes is not too narrow. Further downstream the heat transfer coefficient increases because the previous tubes act as turbulence generators for those which follow. From the fourth or fifth row onwards the flow pattern hardly changes and the mean heat transfer coefficient of the tubes approach a constant end value. As a result of this the mean heat transfer coefficient over all the tubes reaches for an end value independent of the row number. It is roughly constant from about the tenth row onwards. This is illustrated in Fig. 3.26, in which the ratio F of the mean heat transfer coefficient Oim(zR) up to row zR with the end value am (zR —> oo) = amoo is plotted against the row number zR. 

Zukauskas, A. A. Makayawizus, V.I. Zlantzauskas, A. K. Heat transfer in tube bundles with crossflow of fluids (russ.). Vilnjus Mintis 1968... 

Grimison, E.D. Correlation and utilization of new data on flow resistance and heat transfer for crossflow of gases over tube banks. Trans. Amer. Soc. Mech. Eng. 59 (1937)... 

Sulzer SMR static mixer, which has mixing elements made of heat-transfer tubes, and Sulzer s open-crossflow structure catalysts, so-called Katapaks Sulzer (www. sulzer.com) is a Swiss company active in the field of machinery and equipments ... 

S. W. Churchill and M. Berstein, A correlating equation for forced convection from gases and liquids to a circular cylinder in crossflow, J. Heat Transfer, 99,300-306,1977. 

C. M. Chu and J. M. McNaught, Tube Bundle Effects in Crossflow Condensation on Low-Finned Tubes, Proc. 10th Int. Heat Transfer Conf, Brighton, 3, pp. 293-298,1994. 

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