Inclined tubes

Various solutions have been used. These include orifices to regulate the flow into each tube, a blow-through steam technique with a vent condenser, complete separation of each row of tubes, and inclined tubes. 

Natural Gas Condensate in 16 Pipeline o Natural Gas,Oil and Water in 2 Oil Well Tubing o Air and Water in 1 Ver tical Tubing e Air and Lube Oil in 2 Inclined Tubing ... 

The correlation of Akers, et. al., has given good results in some industrial designs. The authors report that some vertical and inclined tube data is also correlated on the same basis. The sharp break in the data occurs around a Reynolds number of 5 X lO as shown in Figure 10-75. The mass flow rate used to correlate is the arithmetic average of inlet and oudet liquid condensate and vapor flows ... 

Experiments in annular flow were performed by Hetsroni et al. (2003b) to study the flow regimes and heat transfer in air-water flow in 8° inclined tubes of inner diameter 49.2 mm and 25 mm. 

In Fig. 5.39a-d the local heat transfer coefficients derived in the horizontal tube are compared to those obtained in the 8° upward inclined pipe and presented by Hetsroni et al. (2006). The results show a clear improvement of the heat transfer coefficient with the pipe inclination. Taitel and Dukler (1976) showed that the flow regimes are very sensitive to the pipe inclination angle. In the flow regime maps presented in their work, the transition from stratified to annular flow in the inclined tube occurs for a smaller air superficial velocity than for the case of the horizontal tube. 

Fig. 5.43 Relative heat transfer coefficients at the top of horizontal and inclined tubes. Horizontal circles (o) indicate FrLs = 0.9, squares ( ) indicate FrLs = 1-3, triangles (A) indicate FrLS = 2.0. Inclined at j8 = 5° filled circles ( ) indicate FrLs = 0.59, filled squares ( ) indicate FrLs = 1.2, filled triangles (A) indicate FrLs = 2.0. Reprinted from Mosyak and Hetsroni (1999) with permission...

Hetsroni G, Hu BG, Yi JH, Mosyak A, Yarin LP, Ziskind G (1998b) Heat transfer in intermittent air-water flows Part II. Int J Multiphase Flow 24(2) 189-212 Hetsroni G, Mewes D, Enke C, Gurevich M, Mosyak A, RozenbUt R (2003b) Heat transfer of two-phase flow in inclined tubes. Int J Multiphase Flow 29 173-194 Hetsroni G, Mosyak A, Segal Z, Pogrebnyak E (2003a) Two-phase flow patterns in parallel microchannels. Int J Multiphase Elow 29 341-360... 

Barnea, D., O. Shoham, Y. Taitel, and A. E. Dukler, 1985, Gas-Liquid Flow in Inclined Tubes Flow Pattern Transitions for Upward Flow, Chem. Eng. Sci. 40(1) 131. (3)... 

Carbon tetrachloride (SG = 1.6) is pumped at a rate of 2 gpm through a pipe that is inclined upward at an angle of 30°. An inclined tube manometer (with a 10° angle of inclination) using mercury as the manometer fluid (SG = 13.6) is connected between two taps on the pipe that are 2 ft apart. The manometer... 

Provided that the walls of the vessel are vertical and that the cross-sectional area does not vary with depth, the shape of the vessel has little effect on the sedimentation rate. However, if parts of the walls of the vessel face downwards, as in an inclined tube, or if part of the cross-section is obstructed for a portion of the height, the effect on the sedimentation process may be considerable. 

Pearce(11) studied the effect of a downward-facing surface by considering an inclined tube as shown in Figure 5.5. Starting with a suspension reaching a level AA, if the sludge line falls to a new level BB, then material will tend to settle out from the whole of the... 

Fig. 9.11 Slug flow bubble shapes (a) Eo > 10, M < 10 (low viscosity liquid) (b) viscous liquid (c) inclined tube.

Weber, W. 1956. Systematic investigation of falling ball viscometers with inclined tubes. Kolloid Z. 147, 14-28. 

The acid distillate is neutralised with lead carbonate, heated and filtered, after which, the dry lead salt is decomposed by heating it in an inclined tube, through which passes a current of dry hydrogen sulphide. B.p. 140°. 

Experiments have shown that Eq. (11.63) tends to underestimate the heat transfer rate from a column of tubes, and is thus conservative for design purposes. The actual heat transfer rates are enhanced by several factors not accounted for in the theoretical model discussed above. These factors include such effects as splashing of the film when it impinges on a lower tube, additional condensation on the subcooled film as it falls between tubes, and uneven run-off because of bowed or slightly inclined tubes. 

The phosphorus vapour, escaping from the furnace, passes up a vertical tube which can be cleared of obstructions from time to time by a movable weight. It then passes down an inclined tube D, which is connected with another tube E by a set of vertical tubes T. Both... 

The heat transfer to supercritical carbon dioxide was measured in horizontal, vertical and inclined tubes at constant wall temperature for turbulent flow at Re-numbers between 2300 and lxl 05. The influence of the variation of physical properties due to the vicinity of the critical point was examined, as well as the influence of the direction of flow. Therefore most of the measurements were conducted at pseudocritical points. At those supercritical points the behaviour of the physical properties is similar to the behaviour at the critical point, but to a lesser degree. At such points the heat capacity shows a maximum density, viscosity and heat conductivity are changing very fast. [1]... 

Flow in horizontal tubes as well as inclined tubes can be studied at Pr-numbers from 0.8 to 22, Re-numbers up to 1.5x10s and Gr-number up to 8x10 . 

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