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A theoretical study of fully developed heat transfer for in-line slug flow through unbaffled equilateral triangular bundles is reported. Results are given for the pitch: diameter range 1.05 to 2.00...

The investigation of the laws governing the pipe-line flow of liquids containing solids in suspension has received the attention of a number of investigators in several fields. The presentation and...

Extending the theoretical foundations established in Part I(1), this paper further describes this efficient method of computing the real-time load flow solution for a power system network. An efficient numerical solution technique particularly applicable to this problem is outlined. Relative weighting of the measurements is analyzed in terms of the measurement accuracies. A method is given for dynamic determination of the frequency of the state estimate calculations. The effects of real-time changes in the network are discussed.

The centrifugal pump, by merit of its principle and construction, offers one of the best means for pumping liquids containing relatively high concentrations of suspended material, as is evidenced b...

Under open access environment in the era of deregulated power industry, transmission loss allocation to various transactions is one of the important issues to be solved exactly. Because of the non-linear nature of power flow and power loss, it is very difficult to segregate and to allocate losses among the participants properly. This paper presents a New DC method (NDC) where an efficient loss allocation algorithm has been applied. Considering the impact of every line flow in a network, the loss allocations to the loads have been computed at first and finally the total loss has been allocated to the generators. The effectiveness of this procedure has been studied for the 6-bus and IEEE 118-bus model power systems. Several numerical analyses implicate that the proposed loss allocation procedure including the DC load flow model is reasonably acceptable. Keywords: Transmission loss allocation DC load flow model, Deregulated power market Bangladesh J. Sci. Ind. Res. 42(3), 257-268, 2007

In wetted wall columns, pure carbon dioxide was absorbed in water containing surface active agent.With the increase in the concentration of the agent, rippling on the surface of the liquid film decreased. When the concentration of the agent exceeded a certain value, rippling almost disappeared. The effect of this change in rippling on the rate of mass transfer from gas to liquid across the interface was studied, and the results obtained are shown in Fig. 2 and 3, in which HL is plotted versus Re on logarithmic coordinates.From these results, it appears that with the decrease in rippling, the disturbance caused by the mixing action of ripples decreases and the flow pattern of the liquid film in the pseudo-stream line flow approaches that of the liquid film in the true viscous flow.The results obtained by the present author and the previous investigators3, 6) for the case when there was no rippling, are shown in Figs. 5 and 6, respectively, as the plots of HL/z versus l/p on logarithmic coordinates. The best line through the data can be expressed by Eq. (8). This experimental line lies above the theoretical line based on the unsteady-state diffusion theory derived by Pigford9. The discrepancy between the theory and the experiment is probably due to the difference between the assumed and actual flow conditions for the liquid film.

In missile-loading and certain other transfer systems, large quantities of cryogenic liquids must be transferred in a relatively short time. Such systems must be cooled to the point at which transfer is accomplished as a liquid rather than as a gas in a fraction of a minute, or, at most, in a few minutes. Four significant factors influence the cool-down time of a transfer system: (1) transfer pressure; (2) heat leak to the fluid from the environment; (3) line flow impedance; and (4) quantity of system mass that requires cooling. These factors have been studied experimentally by Burke et al., who have developed an equation for predicting cool-down times of horizontal lines.