Showing papers by "Stuart W. Churchill published in 1980"
TL;DR: In this paper, a solution for steady, fully developed, laminar flow of an incompressible Newtonian fluid through a helically coiled tube of finite pitch was obtained by finite difference calculations.
Abstract: Solutions for steady, fully developed, laminar flow of an incompressible Newtonian fluid through a helically coiled tube of finite pitch were obtained by finite difference calculations. Prior theoretical solutions have apparently been limited to toroidal flow (with zero pitch). The computed results are consistent with those for this limiting case and with prior experimental data for finite pitch. The behavior for helical coils is intermediate between that for a straight pipe and a torus, and, for a moderate degree of pitch differs only slightly from that for a torus. A correlating equation was developed for the friction factor for all Reynolds numbers, all ratios of coil radius to lube radius and all ratios of pitch to coil radius for which the flow remains laminar.
142 citations
TL;DR: In this paper, a simple theory of adiabatic waves, which neglects the diffusion of momentum and energy, accurately predicts the interrelationship between the various dependent variables but neither the strength of the wave nor the rate of decay.
Abstract: Thermoacoustic convection, that is, convection generated in a compressible fluid due to rapid heating of one of the enclosing walls, was studied numerically. Acoustic waves were found to be generated by sinusoidal heating of the wall as well as by a step function. In a finite layer of fluid the pressure wave is reflected back and forth until dissipated by viscosity. The fluctuating velocity generated by the pressure wave greatly enhances the rate of heat transfer over that for pure transient conduction. The same qualitative behavior but widely varying quantitative behavior was computed for different conditions. The simple theory of adiabatic waves, which neglects the diffusion of momentum and energy, accurately predicts the inter-relationship between the various dependent variables but neither the strength of the wave nor the rate of decay. Hence, these two approaches are complementary.
35 citations
TL;DR: Balakrishnan et al. as discussed by the authors presented a new model for the flow of Freshly Prepared Dilute "Macromolecular Solutions", presented at AIChE 86th National Meeting, Houston, Tex.
Abstract: Balakrishnan, C., and R.J. Gordon, “Influence of Molecular Conformation and Intermolecular Interactions on Turbulent Drag Reduction,”]. Appl. Polymer Sci., 19, 909 (1975) Chiou, C.S., and R.J. Gordon, “Vena Contracta Suppression in Dilute Polymer Solutions,” ibid., 21, 1359 (1977). Ferry, J.D., Viscoelastic Properties of Polymers, 2 ed., Wiley, New York (1970). Flory, P.J., Statistical Mechanics of Chain Molecules, Interscience, New York (1969). Hinch, E.J., and C. Elata, “A New Model for the Flow of Freshly Prepared Dilute ‘Macromolecular Solutions,” paper presented at AIChE 86th National Meeting, Houston, Tex. (1979). Zimm, B.H., and D.M. Crothers, “Simplified Rotating Cylindrical Viscometer for DNA,” Proc. N . Aca. of Sciences, 48,905 ( 1962).
12 citations