Abstract
The determination of heat-transfer rates by differential measurements of static pressure and by inlet velocity resulted in lower values and less consistent values than the rates determined by measurement of the surface temperature of the tube. The difference between the two methods can be attributed to a difference in the velocity of steam and water within the tube generally resulting in indications of higher density, as measured at the cold side of the tube, then as computed from the hot-surface temperature measurement and the water velocity entering the tube. Because the effect of rate of heat transfer, total heat absorption, relative rates of absorption along the length of the tube, and velocity of water entering the tube could not be easily segregated the relative velocities of steam and water could not be correlated with the other factors, and further field work on density, as determined differentially from static pressures, is not recommended. Laboratory work in which separate control of the variables is more practical may provide valuable data on bubble slip and circulation factors.
