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Flow Inside Tubes

The total pressure drop for fluids flowing inside straight tubes results from frictional pressure drop as the fluid flows along the tube, from pressure drop as the fluid enters and leaves the tube side heads or channels, and from pressure drop as the fluid enters and leaves the tubes from the heads or channels. The frictional pressure drop can be calculated from the equation  [Pg.39]

For fluids with temperature dependent viscosities, the pressure drop must be corrected by the ratio  [Pg.39]

The pressure drop as the fluid enters and ieaves a radial nozzle at the heads or channels can be calculated as below  [Pg.40]

The pressure drop associated with inlet and outlet nozzles can be reduced by selection of other channel types, but the expense is seldom warranted except for situations in which the pressure drop is critical or costly. [Pg.40]


In the forced convection heat transfer, the heat-transfer coefficient, mainly depends on the fluid velocity because the contribution from natural convection is negligibly small. The dependence of the heat-transfer coefficient, on fluid velocity, which has been observed empirically (1—3), for laminar flow inside tubes, is h for turbulent flow inside tubes, h and for flow outside tubes, h. Flow may be classified as laminar or... [Pg.483]

Mass-Transfer Coefficient Denoted by /c, K, and so on, the mass-transfer coefficient is the ratio of the flux to a concentration (or composition) difference. These coefficients generally represent rates of transfer that are much greater than those that occur by diffusion alone, as a result of convection or turbulence at the interface where mass transfer occurs. There exist several principles that relate that coefficient to the diffusivity and other fluid properties and to the intensity of motion and geometry. Examples that are outlined later are the film theoiy, the surface renewal theoiy, and the penetration the-oiy, all of which pertain to ideahzed cases. For many situations of practical interest like investigating the flow inside tubes and over flat surfaces as well as measuring external flowthrough banks of tubes, in fixed beds of particles, and the like, correlations have been developed that follow the same forms as the above theories. Examples of these are provided in the subsequent section on mass-transfer coefficient correlations. [Pg.592]

Some gas processes use direct fired furnaces. Process fluid flows inside tubes that are exposed to a direct fire. In this case radiant energy is important. Furnaces are not as common as other devices used in production facilities because of the potential fire hazard they represent. Therefore, they are not discussed in this volume. [Pg.10]

Figure 10-47. Flow inside tubes for gas and vapors. Physical property factor depends on viscosity, specific heat, and thermal conductivity. (Used by permission Ning Hsing Chen, Chemical Engineering, V. 66, No. 1, 1959. McGraw-Hill, Inc. All rights reserved.)... Figure 10-47. Flow inside tubes for gas and vapors. Physical property factor depends on viscosity, specific heat, and thermal conductivity. (Used by permission Ning Hsing Chen, Chemical Engineering, V. 66, No. 1, 1959. McGraw-Hill, Inc. All rights reserved.)...
Buthod presents Figure 10-52 for gases flowing inside tubes. Note that the coefficient refers to the outside tube surface area. It is useful for gases other than those shown because the scale can be multiplied by 10 to obtain the proper order of magnitude for specific heat. [Pg.100]

G,. = equivalent mass flow inside tubes, Ib/hr (ft of flow cross section)... [Pg.130]

Friction resistance to flow inside tubes, flow rate into tubes (per tube) ... [Pg.198]

Figure 9.77. Heat transfer factor for flow inside tubes... Figure 9.77. Heat transfer factor for flow inside tubes...
The tube inside heat transfer coefficients and pressure drop can be calculated using the conventional methods for flow inside tubes see Section 12.8, and Volume 1, Chapter 9. If the unit is being used as a vaporiser the existence of two-phase flow in some of the tubes must be taken into account. Bergman (1978b) gives a quick method for estimating two-phase pressure drop in the tubes of fired heaters. [Pg.774]

Q Annual cost of supplying l(ft)(lbf)/h to pump fluid flowing inside tubes, ( )(h)/(ft)(lbf)(year), ... [Pg.424]

Jackson et al. (J2), 1951 Experimental study of film flow inside tube with counter-flow of gas. Film surface velocity deduced from pressure drop readings in gas stream, neglecting wave roughness effects. Surface velocities appear to exceed the theoretical values in the wavy flow regime. [Pg.214]

Pennie and Belanger (Pi), Film thickness measurements in film of 5% aqueous 1952 sodium carbonate solution flowing inside tube (diameter... [Pg.215]

Kamei et al. (K5), 1954 Thicknesses of films flowing inside tubes of diameters 1.90-5.09 cm. measured with zero and cocurrent gas flows. [Pg.216]

Thomas and Portalski (T14), 1958 Experimental study of water film flowing inside tube 1.96 X 98 cm., Nr, = 141-493, counterflow of air. Data on film thicknesses, pressure drop, wave characteristics. [Pg.220]

Hikita (H12), 1959 Experimental study of effects of rippling on rate of absorption of C02 by water films containing surfactants (0.0005-0.05 wt.%), with film flow inside tubes 1.3 cm. X 15-101 cm. Results approach Emmert and Pigford theory (E4) as rippling is damped by surfactants. [Pg.220]

Konobeev et al. (K21), 1961 Experimental study of C02 absorption by water film, with upward and downward cocurrent gas/film flow, inside tubes 1.05-1.66 cm. i.d., 20-87 cm. long. Gas velocities 6-86 m./sec. IVko = 5-105. Length and amplitude of surface ripples and local film thicknesses measured. Rate of mass transfer stated to be function of wave characteristics only. [Pg.224]

HEAT-TRANSFER COEFFICIENTS FOR FLUIDS FLOWING INSIDE TUBES FORCED CONVECTION, SENSIBLE HEAT 7.26... [Pg.252]

PRESSURE DROP FOR FLOW INSIDE TUBES SINGLE-PHASE FLUIDS 7.73... [Pg.253]

Select the appropriate heat-transfer coefficient equation. Heat-transfer coefficients for fluids flowing inside tubes or ducts can be calculated using these equations ... [Pg.277]

Brine flow inside tube 30-50 10 Good 300-500 0.5-1.0 Very good... [Pg.640]

The mechanism of heat flow in forced convection outside tubes differs from that of flow inside tubes, because of differences in the fluid-flow mechanism. As has been shown on pages 59 and 106 no form drag exists inside tubes except perhaps for a short distance at the entrance end, and all friction is wall friction. Because of the lack of form friction, there is no variation in the local heat transfer at different points in a given circumference, and a close analogy exists between friction and heat transfer. An increase in heat transfer is obtainable at the expense of added friction simply by increasing the fluid velocity. Also, a sharp distinction exists between laminar and turbulent flow, which calls for different treatment of heat-transfer relations for the two flow regimes. [Pg.359]

S. I. Evans and R. J. Sarjant, Heat Transfer and Turbulence in Gases Flowing Inside Tubes, / Inst. Fuel (24) 216-227,1951. [Pg.853]

Coefficient of Heat Transfer for Flow Inside Tubes... [Pg.46]


See other pages where Flow Inside Tubes is mentioned: [Pg.274]    [Pg.260]    [Pg.14]    [Pg.14]    [Pg.1387]    [Pg.102]    [Pg.39]    [Pg.75]   


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