(2)
Divide each product by the total barrels.
JP-8:
32.4%
DF-2:
24.3%
MOGAS:
43.3%
(3) Discard from consideration any not meeting criterion of 24 percent or more. Here,
however, all three products met the criterion of 24 percent or more. We must now determine which
product is the heaviest. Using FM 5-482, Table 4-1, find the average specific gravity for each product.
Since DF-2 is the heaviest product, it will become the Design Fuel.
e. Theory of Flow. Theory of flow studies the characteristics of liquids in motion. This is of
particular importance when we design pipelines. To ensure we correctly place our pump stations along
the pipeline and can maintain a desired flow rate we must understand how flow rates are affected by
friction. There are several steps, which must be done to determine head loss due to friction (Hf).
Understand that when a liquid moves through a pipe, friction occurs between the liquid and the inside
pipe wall. It is this friction that causes the liquid to slow its advance forward. We can overcome our
head loss due to friction if we know what the head loss per given distance is going to be. The Reynolds
number is the pivotal formula in determining our head loss due to friction. Remember, Reynold's
number is dimensionless.
(1) The effect of pipe diameter, internal forces, and viscous forces is considered in the
Reynold's number. Two formulas can be used in determining Reynold's number depending on whether
the pipeline is in a developmental stage or in place. If the pipeline is in development, use the Design
Data formula; otherwise, use the field data formula.
(a)
Formula for Reynold's Number using design data:
R = V D Where: V = velocity in feet per second
Y
D = inside diameter of pipe in feet
Y = Kinematic viscosity in squared feet per second
(b)
Formula for Reynold's Number using field data:
R = 3160 x Q Where: 3160 = constant.
dxk
Q =flow rate in GPM
d = inside diameter of pipe in inches
k = Kinematic viscosity in centistokes
1-14
QM5203
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