Nomenclature heat transfer

Specialized heat transfer nomenclature used for radiative heat transfer is defined in the subsection Heat Transmission hy Radiation. Nomenclature for mass transfer is defined in the subsection Mass Transfer. ... 

Nomenclature (Use consistent units.) A = heat-transfer surface C, c = specific heats of hot and cold fluids respectively Lq = flow rate of liquid added to tank M = mass of fluid in tank T, t = temperature of hot and cold fluids respectively Ti, ti = temperatures at beginning of heating or cooling period or at inlet To, to = temperature at end of period or at outlet To, to of liquid added to tank ... 

Figure 10-137. Heating and cooling in tube bundles—tube-side friction factor. (Used by permission Kern, D. Q. Process Heat Transfer, 1 Ed., p. 836, 1950. McGraw-Hill, Inc. All rights reserved. Using nomenclature of Standards of Tubular Exchanger Manufacturers Association.)...

The overall heat transmittance from tracer through heat transfer cement to process pipe, qt, in Btu/(hr) (fti)(°F) is given in Table 10-47. From the detailed articles of Foo, the following nomenclature applies ... 

The nomenclature is as follows Qm is the rate of heat transfer from the reactor to the reactor wall, Qj is the rate of heat transfer from the reactor wall to the jacket, and... 

Shah and London [40] have compiled the heat-transfer and fluid-friction information for fully developed laminar flow in ducts with a variety of flow cross sections as shown in Table 6-1. In this table the following nomenclature applies ... 

The heat transfer is then calculated from Eq. (8-43), with appropriate change of nomenclature ... 

For simplification, assume that the oil-film heat-transfer coefficient may be represented by (standard heat-transfer nomenclature)... 

Nomenclature and Units—Heat Transfer by Conduction, by Convection, and with Phase Change... 

The nomenclature of the equations above is tj and t2 - temperature of fluid 1 and fluid 2 respectively, wj and W2 - mean velocities for hot and cold fluid, pj and p2 - fluid densities, Cpj and Cp2 - fluid sensible heats, d and D - specific diameters of the basic pipe and mantle of the heat exchanger, Uj and U2 - partial heat transfer coefficients around the basic pipe, 5p and Sp - thickness of the basic pipe and the mantle, Xp and Xp - thermal conductivities of the basic pipe and mantle walls, k and kg - total heat transfer coefficients, tg - external temperature of the heat exchanger. 

The study of evaporating rivulet flow shows that macroscopic flow and heat transfer may be considerably changed itself by microscopic heat transfer, the example is establishing of thermal apparent contact angle in case of rivulet evaporation. Extremely high evaporation rate in thin film area changes the slope of interface as far as macro flow curvature and wave patterns. NOMENCLATURE... 

The parameters and din re the mass and heat transfer groups defined in terms of common physical properties (see Nomenclature). 

Here P indicates the effectiveness of the heat exchanger (to be elaborated in Section 7.4) and R (from its definition) is the ratio of the heat-capacity flow rates Note the change in nomenclature from subscripts h and c to t and s, the latter two referring to tube and shell, respectively. An important fact is that whether the hot (or cold) fluid is flowing in the shell side or in the tubes has no effect on F as long as the heat transfer to the ambient is negligible. Otherwise, the cold fluid should be in the shell side to reduce heat losses Combination of Eqs (7.28) and (7.29) gives... 

The author gratefully acknowledges the use of a number of thermophysical property tables from previous editions of Handbook of Heat Transfer. These include Table 12 from the first edition, prepared by Professor Warren Ibele of the University of Minnesota, and Tables 11, 12,14,16,21,29,30, and 33, prepared by Professor Peter Liley of Purdue University. NOMENCLATURE ... 

Equations are presented in this section for evaluating the heat transfer by natural convection from the external surfaces of bodies of various shapes. The correlation equations are of the form described in the section on the heat transfer correlation method, and the orientation of the surface is given by the surface angle defined in Fig. 4.4. Supporting experimental evidence for each such equation set is outlined after each equation tabulation. The correlations are in terms of Nu, Ra, and Pr, parameters that involve physical properties, a length scale, and a reference temperature difference. Rules for the evaluation of property values are provided in the nomenclature, and the relevant length scale and reference temperature difference are provided in a separate definition sketch for each problem. 

Correlation. In terms of quantities defined in Fig. 4.6 and the nomenclature, the total heat transfer from a wide (W L) vertical isothermal plate can be estimated from the following equations ... 

Correlation. The objective is to calculate the heat transfer from the lateral surface of the long vertical cylinder or wire, where heat transfer from the ends is ignored. See Fig. 4.14 for relevant nomenclature. 

Long Inclined Circular Cylinder, Laminar Flow. See Fig. 4.16c for nomenclature. The cylinder axis is inclined from the horizontal at an angle 0. The heat transfer from the ends is ignored, which will be valid for insulated ends or for LID 5. The analysis of Raithby and Hollands [225, 226] led to the following correlation ... 

FIGURE 4.21 Geometry and nomenclature for natural convection heat transfer from a wide (W S) rectangular cooling slot with heat flux or temperature-specified conditions on the walls. 

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