Concurrent studies of enhanced heat transfer and materials for ocean thermal exchangers. Summary of progress to December 15, 1977

Research progress is briefly reported in the areas of 1) working-fluid heat transfer, 2) water-side heat transfer, 3) erosion of flutes, 4) pressure drop in shell-side vapor and distribution of liquid working fluid, 5) Argonne core tests, 6) water distribution in headers, 7) transient modeling and control, and 8) vertical-tube evaporators. (WHK

Heat transfer research and power cycle transient modeling

Fine axial flutes enhance heat transfer in vertical shell-and-tube exchangers with water inside the tubes and ammonia evaporating or condensing in layer flow on the shell side. Single-tube experiments with R-11 and ammonia indicate local shell-side coefficients 3 to 5 times those for corresponding smooth tubes. Single-tube experiments with water indicate that at moderate velocities the tube-side coefficients are enhanced by a factor equal to the ratio of fluted-to-smooth surface areas while the fluid friction is similarly increased. The experimental data are transformed into mean individual coefficients for ammonia and water. Overall coefficients for a particular case are presented to illustrate the efficacy of enhancement by flutes on one or both sides of the heat transfer surface. Means are described for using emerging data to predict the static and dynamic behavior of the power cycle and the interactions of components throughout the complete power plant