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3 years ago

1:

Engineering

1 answer:

Nataly [62]3 years ago

7 0

Answer:

20.87 Pa

Explanation:

The formula for dynamic pressure is given as;

q= 1/2*ρ*v²

where ;

q=dynamic pressure

ρ = density of fluid

v = velocity of fluid

First find v by applying the formula for flow rate as;

Q = v*A where ;

Q= fluid flow rate

v = flow velocity

A= cross-sectional area.

A= cross-sectional vector area of the pipe given by the formula;

A= πr² = 3.14 * 4² = 50.27 in² where r=radius of pipe obtained from the diameter given divided by 2.

Q = fluid flow rate = 105 gpm----change to m³/s as

1 gpm = 0.00006309

105 gpm = 105 * 0.00006309 = 0.006624 m³/s

A= cross-sectional vector area = 50.27 in² -------change to m² as:

1 in² = 0.0006452 m²

50.27 in² = 50.27 * 0.0006452 = 0.03243 m²

Now calculate flow velocity as;

Q =v * A

Q/A = v

0.006624 m³/s / 0.03243 m² =v

0.2043 m/s = v

Now find the dynamic pressure q given as;

q= 1/2 * ρ*v²

q= 1/2 * 1000 * 0.2043² = 20.87 Pa

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