Optimum economic pipe diameter

A graphical representation showing the meaning of an optimum economic pipe diameter is presented in Fig. 1-1. As shown in this figure, the pumping cost increases with decreased size of pipe diameter because of frictional effects, while the fixed charges for the pipeline become lower when smaller pipe diameters are used because of the reduced capital investment. The optimum economic diameter is located where the sum of the pumping costs and fixed costs for the pipeline becomes a minimum, since this represents the point of least total cost. In Fig. 1-1, this point is represented by E. 

Determination of optimum economic pipe diameter for constant mass-throughput rate. 

A classic example showing how added refinements can come into an analysis for optimum conditions is involved in the development of methods for determining optimum economic pipe diameter for transportation of fluids. The following analysis, dealing with economic pipe diameters, gives a detailed derivation to illustrate how simplified expressions for optimum conditions can be developed. Further discussion showing the effects of other variables on the sensitivity is also presented. 

FLUID DYNAMICS (OPTIMUM ECONOMIC PIPE DIAMETER)... 

The preceding analysis clearly neglects a number of factors that may have an influence on the optimum economic pipe diameter, such as cost of capital or return on investment, cost of pumping equipment, taxes, and the time value of money. If the preceding development of Eq. (39) for turbulent flow is refined to include the effects of taxes and the cost of capital (or return on investment) plus a more accurate expression for the frictional loss due to fittings and bends, the result is t... 

Prepare a plot of optimum economic pipe diameter versus the flow rate of fluid in the pipe under the following conditions ... 

For the conditions indicated in Prob. 7, prepare a log-log plot of fluid velocity in feet per second versus optimum economic pipe diameter in inches. The plot should cover a fluid-velocity range of 1 to 100 ft/s and a pipe-diameter range of 1 to 10 in. 

Derive Eq. (49) for the optimum economic pipe diameter and compare this to the equivalent expression presented as Eq. (5-90) in J. H. Peny and C. H. Chilton, ed., Chemical Engineers Handbook, 5th ed., p. 5-32, McGraw-Hill Book Company, New York, 1973. 

The derivation of equations for determining optimum economic pipe diameters is presented in Chap. 11 (Optimum Design and Design Strategy). The following simplified equations [Eqs. (45) and (47) from Chap. 11] can be used for making design estimates ... 

Nomograph for estimation of optimum economic pipe diameters with turbulent or viscous flow based on Eqs. (15) and (16). 

Incineration, 88-89 Income statemenf 142-145 Income-tax effects on cost of capital, 248-249 on optimum economic pipe diameter, 366-367 on profitability evaluation, 300, 324... 

The only variable that will appear in the resulting total-cost expressions is the pipe diameter. The optimum economic pipe diameter can be generated by taking the... 

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