The formula to calculate the flow rate of natural gas through a pipe is:
\[ q = 3550 \left[ \frac{d^5}{1 + \frac{3.6}{d} + 0.03d} \right]^{1/2} \left( \frac{h}{L \cdot SG} \right)^{1/2} \]
Where:
The correct gas pipe size depends on the diameter, length, and pressure drop of the pipe. It also depends on the specific gravity of the gas moving through the pipe.
Example 1:
Using the formula:
\[ q = 3550 \left[ \frac{2^5}{1 + \frac{3.6}{2} + 0.03 \cdot 2} \right]^{1/2} \left( \frac{10}{50 \cdot 0.60} \right)^{1/2} \]
Calculating step-by-step:
\[ q = 3550 \left[ \frac{32}{1 + 1.8 + 0.06} \right]^{1/2} \left( \frac{10}{30} \right)^{1/2} \]
\[ q = 3550 \left[ \frac{32}{2.86} \right]^{1/2} \left( \frac{1}{3} \right)^{1/2} \]
\[ q = 3550 \left[ 11.19 \right]^{1/2} \left( 0.333 \right)^{1/2} \]
\[ q = 3550 \cdot 3.34 \cdot 0.577 \]
\[ q \approx 6855.8 \text{ cfh} \]
Example 2:
Using the formula:
\[ q = 3550 \left[ \frac{3^5}{1 + \frac{3.6}{3} + 0.03 \cdot 3} \right]^{1/2} \left( \frac{15}{100 \cdot 0.60} \right)^{1/2} \]
Calculating step-by-step:
\[ q = 3550 \left[ \frac{243}{1 + 1.2 + 0.09} \right]^{1/2} \left( \frac{15}{60} \right)^{1/2} \]
\[ q = 3550 \left[ \frac{243}{2.29} \right]^{1/2} \left( \frac{1}{4} \right)^{1/2} \]
\[ q = 3550 \left[ 106.11 \right]^{1/2} \left( 0.25 \right)^{1/2} \]
\[ q = 3550 \cdot 10.30 \cdot 0.5 \]
\[ q \approx 18282.75 \text{ cfh} \]
