98--The differential equations governing streams

doi:10.1615/hedhme.a.000098

Navigation by alphabet

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Hagen-Poiseuille law Hagen-Rubens relation, between electrical and optical constants, Hall Taylor, N S, Halogenated hydrocarbons: Handley and Heggs equation for fixed bed pressure drop, Hankinson and Thomson method, for liquid density: Hardening (precipative) of stainless steels, Hardwick, R, Harris, D, Hausen equation for developing laminar flow, Hays, G F Headers in shell-and-tube heat exchangers, Heads, in heat exchangers: Heat and mass transfer: Heat exchanger design, introduction, Heat exchangers:

condensers, corrosion and other damage, costing, definitions and quantitative relationships,

Thermodynamics: Brief notes on important concepts It's an article balance equations for equipment, differential equations for streams in,

The differential equations governing streams It's an article

flux relationships, partial differential equations for interpenetrating continua in, thermodynamic concepts, transfer coefficient dependences,

description of, design, double pipe, effectiveness of: entropy generation in, F-correction method for F-factor charts for, fouling of, gas-liquid pressure drop in, heat pipe, mechanical design: air-cooled, networks of, pinch analysis method for, numerical solution methods for: with calculation of flow pattern, plate fin, plate, thermal design of, P-NTU method for practical aspects of operation, pressure drop in headers, nozzles, and turnarounds, representation as interpenetrating continua, safety of shell-and-tube (single phase), thermal design of suction line exchangers in refrigeration, twisted tube, with dimpled surfaces, with tube inserts, Θ-method for Θ-method chart for,

Heat of vaporisation (see Enthalpy of vaporisation), of pure substances Heat pipes: Heat pumping, relation to heat exchanger network design, Heat storage (see Regenerators and thermal energy storage) entropy generation in, Heat transfer: Heat transfer coefficient: Heat transfer media, Heat transfer salt, Heat transfer regimes: Heat of vaporization, Heated cavity reflectometer, Heating media, for reboilers, Heavy water, physical properties of, Heggs, P J, Helical coils of circular cross section: Helical coils of rectangular cross section, Helical inserts, for enhancement of heat transfer in boiling, Helium: Helmholtz reciprocity principle, in radiative heat transfer, Henry, J A R, Henry-Fauske model, for critical two-phase flow, Henry's law, for partial pressure, Heptadecane: Heptadecene: Heptane: 1-Heptanol: 1-Heptene: Herman, K W, Hermes, C L L, Heterogeneous conveyance in horizontal pipes, Heterogeneous nucleation in boiling, Hewitt, G F Hexachloroethane (Refrigerant 116): Hexacyclopentane, superheated vapor properties, Hexadecane: Hexadecene: 1,5-Hexadiene: Hexagonal cells, in free convection, Hexamethylbenzene: Hexane: Hexanoic acid: 1-Hexanol: 1-Hexene: Hexylbenzene: Hexylcyclohexane: Hexylcyclopentane, Hicks equation, for fixed-bed pressure drop, High pressure closures, ASME VIII code guidance for, High-chrome steels, thermal and mechanical properties, High-finned tubes, correlations for single-phase heat transfer in flow over, Hills, P D Hohlraum cavity, Holdup, in liquid-liquid flow, Holland, guide to national practice for mechanical design of heat exchangers, Homogeneous condensation (fog formation), Homogeneous model: Homogeneous nucleation: Honeycombs: Hopkins, D, Horizontal condensers: Horizontal cylinders: Horizontal layers, of fluid, free convection heat transfer in, Horizontal pipes: Horizontal shell-side evaporator, Horizontal surfaces: Horizontal thermosiphon reboilers: Horizontal tube-side evaporator, Horizontal tubes: Hottel's rule, in absorption of radiation by gases, Hsu criterion, for onset of nucleate boiling, Hybrid cooling towers, Hydraulic conveyance: Hydraulic expansion, of tubes into tube sheets in shell-and-tube heat exchangers, Hydraulic turbine, lost work in, Hydraulic resistance, in flow of supercritical fluids, Hydraulically smooth surface, Hydrazine: Hydrocarbons: Hydrodynamic entrance length, in single-phase flow in ducts, Hydrogen: Hydrogen bromide: Hydrogen chloride: Hydrogen cyanide: Hydrogen fluoride: Hydrogen iodide: Hydrogen peroxide: Hydrogen sulfide: Hydrostatic testing of shell-and-tube heat exchangers, Hysteresis:

Index

HEDH

A B C D E F G H

condensers, corrosion and other damage, costing, definitions and quantitative relationships,

Thermodynamics: Brief notes on important concepts It's an article balance equations for equipment, differential equations for streams in,

The differential equations governing streams It's an article

flux relationships, partial differential equations for interpenetrating continua in, thermodynamic concepts, transfer coefficient dependences,

I J K L M N O P Q R S T U V W X Y Z

H Heat exchangers: definitions and quantitative relationships, differential equations for streams in,

Download the citation in the EndNote formatOpen in a new tab. Download the citation in the RefWorks formatOpen in a new tab. Download the citation in the BibTex formatOpen in a new tab.

The differential equations governing streams

DOI 10.1615/hedhme.a.000098

1.2 DEFINITIONS AND RELATIONSHIPS
1.2.5 Differential Equations Governing Streams

D. Brian Spalding

A. DIFFERENTIAL EQUATIONS FOR ENTHALPY

Figure 1 represents an elementary portion of stream 1 in a heat exchanger. The length of the path in the flow direction is dz₁ and the associated interface area is dA. If the flow is steady, and effects of kinetic heating, external work, and gravitational potential energy are negligible, the application of the steady-flow energy equation, 1.2.1(3), yields

\[\label{eq125_1} \frac{\dot {M}_1 dh_1 }{dz_1 } = - \dot {q}_{1 \to 2} \frac{dA}{dz_1 } \tag{1}\]

where q̇_1→2 is the heat flux per unit area from stream 1 to stream 2. This heat flux can of course be calculated from

\[\label{eq125_2} \dot {q}_{1 \to 2} = U\left( {T_1 - T_2 } \right) \tag{2}\]

... You need a subscriptionOpen in a new tab. to view the full text of the article. If you already have the subscription, please login here