A heat transfer textbook

https://www.eis.hu.edu.jo/deanshipfiles/pub10311353.pdf

Numerical study of natural convection in partially heated rectangular enclosures filled with nanofluids

Correlating equations for laminar and turbulent free convection from a vertical plate

Correlating equations for laminar and turbulent free convection from a horizontal cylinder

A single comprehensive equation is developed for the rate of heat and mass transfer from a circular cylinder in crossflow, covering a complete range of Pr (or Sc) and the entire range of Re for which data are available. This expression is a lower bound (except possibly for RePr < 0.2); free-stream turbulence, end effects, channel blockage, free convection, etc., may increase the rate. In the complete absence of free convection, the theoretical expression of Nakai and Okazaki may be more accurate for RePr < 0.2. The correlating equation is based on theoretical results for the effect of Pr in the laminar boundary layer, and on both theoretical and experimental results for the effect of Re. The process of correlation reveals the need for theoretical results for the effect of Pr in the region of the wake. Additional experimental data for the effect of Pr at small Pe and for the effect of Re during the transition in the point of separation are also needed.

A Correlating Equation for Forced Convection From Gases and Liquids to a Circular Cylinder in Crossflow

The computed characteristics of turbulent flow and convection in concentric circular annuli. Part IV: Generalizations

The computed characteristics of turbulent flow and convection in concentric circular annuli. Part III. Alternative thermal boundary conditions

Numerical solutions have been carried out for representative conditions in a tubular reactor in fully developed laminar and turbulent flow. The computations are unique in two respects. First, they take into account the radial transport of both species and energy by molecular and turbulent fluctuations for the combination of energetic reactions and heat exchange with the surroundings. Second, those for turbulent flow are based on an essentially exact model for transport by the fluctuating velocities, concentrations, and temperature. The mixed-mean conversion for finite radial rates of transport is found to differ significantly from those for the common idealizations of negligible or perfect radial mixing. Although the numerical solutions are essentially exact, some idealizations such as invariant physical properties and a rate mechanism in terms of concentration have been made in the interests of generality. The numerical results are limited to a single first-order irreversible equimolar reaction, but the ...

Effects of Transport on Reactions in Homogeneous Tubular Flow

Previous studies of combustion in a refractory tube with premixed propane and air or vaporized hexane droplets in air have demonstrated the existence of multiple stationary states; thin, stable and non-oscillatory flames; and a low production of thermal NOx (5–40 ppm). These studies were all limited to an equivalence ratio of approximately 0.80. In the current work a complete range of equivalence ratios was investigated for hexane droplets, vaporized completely prior to combustion. The concentration of thermal NOx was found to peak at about 100 ppm for the stoichiometric ratio, to fall off rapidly as the equivalence ratio increased above unity and to fall off even more rapidly to less than 5 ppm as the equivalence ratio decreased to 0.6. The decrease for 1 is presumably due to the absence of free oxygen as well. Experiments were also carried out for hexane doped with 0.795% wt. nitrogen in the form of diethylamine, isobutylamine, pyridine and piperidine. The formation of NOx from these materials was found to be independent of the residence time in the post-flame zone. This result implies complete conversion within the flame front in accordance with prior conjectures. The conversion of fuel-nitrogen to NOx was essentially 100% for 0.6 1 and precipitously for 1, again in agreement with the observations of prior investigators for flat laminar flames.

/pdf/the-formation-of-thermal-and-fuel-nox-for-radiantly-1jvfeelvm6.pdf

Stuart W. Churchill

Papers

The computed characteristics of turbulent flow and convection in concentric circular annuli. Part IV: Generalizations

The computed characteristics of turbulent flow and convection in concentric circular annuli. Part III. Alternative thermal boundary conditions

Effects of Transport on Reactions in Homogeneous Tubular Flow

THE FORMATION OF THERMAL AND FUEL NOx FOR RADIANTLY STABILIZED COMBUSTION

Coefficients for Calculation of Freezing in a Semi-Infinite Region