Pressure drop Water flow , table

To illustrate this methodology, we show the case of pressure drop per unit length for one-phase flow in a packed bed. In laboratories, the pressure drop is measured over a 0.1 m length of packed bed using an apparatus as shown in Fig. 6.11. The fluid used is water at 20 °C (p = 1000 kg/m, t) = 10 kg/ms). While the tests are carried out the velocity is varied and the corresponding pressure drop is measured. Table 6.5 shows the results of these tests. 

Strainers should be selected so that die pressure drop incurred does not exceed a specified limit with a clean strainer basket (typically 2 psi). Pressure drop versus flow capacity curves for basket strainers are given in Figure 16. This plot provides gross pressure drop for different capacities of water flow at suitable strainer p sizes. The value obtained must be corrected on the basis of the actual fluid viscosity and strainer opening size to be used. These corrections are given in Table 5 and the procedure is as follows ... 

A summary of the nine batch reactor emulsion polymerizations and fifteen tubular reactor emulsion polymerizations are presented in Tables III IV. Also, many tubular reactor pressure drop measurements were performed at different Reynolds numbers using distilled water to determined the laminar-turbulent transitional flow regime. 

The relationship between flow rate, pressure drop, and pipe diameter for water flowing at 60°F in Schedule 40 horizontal pipe is tabulated in Appendix G over a range of pipe velocities that cover the most likely conditions. For this special case, no iteration or other calculation procedures are required for any of the unknown driving force, unknown flow rate, or unknown diameter problems (although interpolation in the table is usually necessary). Note that the friction loss is tabulated in this table as pressure drop (in psi) per 100 ft of pipe, which is equivalent to 100pef/144L in Bernoulli s equation, where p is in lbm/ft3, ef is in ft lbf/lbm, and L is in ft. 

Through circulation dryers employ perforated or open screen bottom tray construction and have baffles that force the air through the bed. Superficial velocities of 150 ft/min are usual, with pressure drops of 1 in. or so of water. If it is not naturally granular, the material may be preformed by extrusion, pelleting, or briquetting so that it can be dried in this way. Drying rates are greater than in cross flow. Rates of 0.2-2 lb/(hr)(sqft tray area) and thermal efficiencies of 50% are realized. Table 9.7(d) has performance data. 

Evaluating the Flow Curve from Experimental Data The flow rate of 3% CMC solution in water was measured in a long capillary as a function of pressure drop. Based on the results given in the following table, compute the non-Newtonian viscosity versus the shear-rate curve. 

The flow of water required to cool the oil is 23310 Ib/hr. The computer program PROG83 rates the double pipe heat exchanger using either fin tubes or bare tubes. Table 8-23 lists the input data and output of the computer program. The fin efficiency is 43.3 percent and the computed overall heat transfer coefficient is 27.3 Btu/hrft °F. The pressure drops have not been exceeded, and the double pipe exchanger will be satisfactory for the service. 

For the special case of water at 60°F in sch 40 steel (s = 0.045 mm or 0.0018 in.) pipe, the relation between flow rate, velocity, pressure drop, and pipe size is tabulated in Table 5.4. The range of values tabulated covers most of the range that would be expected in practice. Note that the friction loss is tabulated as pressure drop in psi per 100 ft of pipe, which is equivalent to (100 pe/T) in English engineering units. 

Figure 6.13 is a convenience chart made up from Fig. 6.10. It is well suited to the needs of an oil company, which spends large sums of money in pumping fluids with a wide range of viscosities but it is poorly suited to the needs of a city water supply company, which deals almost exclusively with water. When Fig. 6.13 was made from Fig. 6.10, the pipe diameter and roughness were held constant. If we are dealing with water, we can assume that the temperature is constant (which is approximately true in city water systems) and that the absolute roughness of the pipe wall is constant. Then the pressure drop as a function of pipe diameter and flow rate can be tabulated for all flows of water at the chosen temperature. Appendix A.4 is such a table, made up for the flow of water I at 60°F through schedule 40 pipe (the most common size in U.S. industrial practice).

The reactor is assumed to be adiabatic with plug flow. Axial dispersion can be ignored. Any effect of limitations of mass or heat transfer inside the catalyst pellet is lumped into the rate constants given in Table 1. The catalyst activity is assumed to be constant. Use the conversion of ethylbenzene or water in the set of continuity equations. Use the Ergun equation to describe the pressure drop. 

Hydrodynamics, pressure drop, and mass transfer during liquid-liquid flows were investigated in two different systems, viz. in glass microchannels with circular cross section of 0.2 mm ID (Fig. 3.3a, b) using an ionic liquid and deionised water, and in Teflon channels of different sizes, i.e. 0.2-2 mm ID (Fig. 3.3c) using either different TBP/ionic liquid mixtures (30 %, v/v) (Table 3.2) and aqueous nitric acid solutions, relevant to spent nuclear fuel reprocessing, or ionic Uquid and deionised water. The internal diameter of the microchannels was measured using a microscope (Nikon Eclipse ME 600). 

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