Ask The Brewmasters

What pressure do you have coming in from the city, in that 1.5" line?

Hi Craig, they have 40 psig coming into the building.

What pressure do you have coming in from the city, in that 1.5" line?

I did some math with a few online calculators, and I'm getting varied results:

"40PSI at 1.5" = 110 GPM maximum capacity"

(https://resources.hy-techroof.com/blog/how-much-water-can-flow-through-a-pipe)

ChatGPT spit out this gem:

To determine the flow rate in gallons per minute (GPM), we need to solve for the flow velocity ($V$) using the Darcy-Weisbach equation and then use the cross-sectional area of the pipe to calculate the flow rate.

Given the parameters provided:

• Equivalent length of the pipe ($L$): 220 feet
• Pipe diameter ($D$): 0.125 feet (1.5 inches)
• Density of water ($\rho$): 62.4 lb/ft³
• Darcy friction factor ($f$): 0.02 (assumed)
• Pressure drop ($\Delta P$) from 40 PSI to atmospheric pressure: 40 PSI - 14.7 PSI = 25.3 PSI

Now, let's plug these values into the Darcy-Weisbach equation to find the flow velocity ($V$):

<math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>V</mi><mo>=</mo><msqrt><mfrac><mrow><mn>2</mn><mo>×</mo><mi mathvariant="normal">Δ</mi><mi>P</mi><mo>×</mo><mi>D</mi></mrow><mrow><mi>f</mi><mo>×</mo><mi>L</mi><mo>×</mo><mi>ρ</mi></mrow></mfrac></msqrt></mrow></semantics></math>V=f×L×ρ2×ΔP×D​

​

<math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>V</mi><mo>=</mo><msqrt><mfrac><mrow><mn>2</mn><mo>×</mo><mn>25.3</mn><mo>×</mo><mn>0.125</mn></mrow><mrow><mn>0.02</mn><mo>×</mo><mn>220</mn><mo>×</mo><mn>62.4</mn></mrow></mfrac></msqrt></mrow></semantics></math>V=0.02×220×62.42×25.3×0.125​

​

<math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>V</mi><mo>≈</mo><msqrt><mfrac><mn>6.325</mn><mn>27.456</mn></mfrac></msqrt></mrow></semantics></math>V≈27.4566.325​

​

<math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>V</mi><mo>≈</mo><msqrt><mn>0.23</mn></msqrt></mrow></semantics></math>V≈0.23

​

$V\approx 0.479\text{ft/s}$

Now, we can calculate the flow rate ($Q$) using the formula:

$Q=A\times V$

Where $A$ is the cross-sectional area of the pipe. The cross-sectional area of a pipe with diameter $D$ is:

<math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>A</mi><mo>=</mo><mi>π</mi><mo>×</mo><msup><mrow><mo fence="true">(</mo><mfrac><mi>D</mi><mn>2</mn></mfrac><mo fence="true">)</mo></mrow><mn>2</mn></msup></mrow></semantics></math>A=π×(2D​)2

<math xmlns="http://www.w3.org/1998/Math/MathML"><semantics><mrow><mi>A</mi><mo>=</mo><mi>π</mi><mo>×</mo><msup><mrow><mo fence="true">(</mo><mfrac><mn>0.125</mn><mn>2</mn></mfrac><mo fence="true">)</mo></mrow><mn>2</mn></msup></mrow></semantics></math>A=π×(20.125​)2

$A=\pi \times 0.0625$

$A\approx 0.1963\text{square feet}$

Now, we can calculate the flow rate:

$Q=0.1963\times 0.479$

$Q\approx 0.094\text{cubic feet per second (cfs)}$

To convert cubic feet per second to gallons per minute, we need to multiply by a conversion factor. Since 1 cubic foot per second is approximately 448.831 gallons per minute, we'll use that conversion factor:

$Q\approx 0.094\times 448.831$

$Q\approx 42.285\text{GPM}$

So, approximately 42.285 gallons per minute will flow from the 1.5" copper pipe at 40 PSI with the given conditions.

Another site had around 85.

We're actually doing this math now, expanding and adding a brewhouse. The engineers are insisting we add a city water buffer tank, as the new house will probably consume more than we can supply (even with a 2" line at like 90psi lol). A buffer tank and a pump may be the way your buddy needs to go too.

Hi Craig, they have 40 psig coming into the building.

What pressure do you have coming in from the city, in that 1.5" line?

I did some math with a few online calculators, and I'm getting varied results:

"40PSI at 1.5" = 110 GPM maximum capacity"

(https://resources.hy-techroof.com/blog/how-much-water-can-flow-through-a-pipe)

ChatGPT spit out this gem:

To determine the flow rate in gallons per minute (GPM), we need to solve for the flow velocity ($V$) using the Darcy-Weisbach equation and then use the cross-sectional area of the pipe to calculate the flow rate.

Given the parameters provided:

• Equivalent length of the pipe ($L$): 220 feet
• Pipe diameter ($D$): 0.125 feet (1.5 inches)
• Density of water ($\rho$): 62.4 lb/ft³
• Darcy friction factor ($f$): 0.02 (assumed)
• Pressure drop ($\Delta P$) from 40 PSI to atmospheric pressure: 40 PSI - 14.7 PSI = 25.3 PSI

Now, let's plug these values into the Darcy-Weisbach equation to find the flow velocity ($V$):

V=f×L×ρ2×ΔP×D​

​

V=0.02×220×62.42×25.3×0.125​

​

V≈27.4566.325​

​

V≈0.23

​

$V\approx 0.479\text{ft/s}$

Now, we can calculate the flow rate ($Q$) using the formula:

$Q=A\times V$

Where $A$ is the cross-sectional area of the pipe. The cross-sectional area of a pipe with diameter $D$ is:

A=π×(2D​)2

A=π×(20.125​)2

$A=\pi \times 0.0625$

$A\approx 0.1963\text{square feet}$

Now, we can calculate the flow rate:

$Q=0.1963\times 0.479$

$Q\approx 0.094\text{cubic feet per second (cfs)}$

To convert cubic feet per second to gallons per minute, we need to multiply by a conversion factor. Since 1 cubic foot per second is approximately 448.831 gallons per minute, we'll use that conversion factor:

$Q\approx 0.094\times 448.831$

$Q\approx 42.285\text{GPM}$

So, approximately 42.285 gallons per minute will flow from the 1.5" copper pipe at 40 PSI with the given conditions.

Another site had around 85.

We're actually doing this math now, expanding and adding a brewhouse. The engineers are insisting we add a city water buffer tank, as the new house will probably consume more than we can supply (even with a 2" line at like 90psi lol). A buffer tank and a pump may be the way your buddy needs to go too.

Hi Craig, they have 40 psig coming into the building.

I did some math with a few online calculators, and I'm getting varied results:

"40PSI at 1.5" = 110 GPM maximum capacity"

(https://resources.hy-techroof.com/blog/how-much-water-can-flow-through-a-pipe)

ChatGPT spit out this gem:

To determine the flow rate in gallons per minute (GPM), we need to solve for the flow velocity ($V$) using the Darcy-Weisbach equation and then use the cross-sectional area of the pipe to calculate the flow rate.

Given the parameters provided:

• Equivalent length of the pipe ($L$): 220 feet
• Pipe diameter ($D$): 0.125 feet (1.5 inches)
• Density of water ($\rho$): 62.4 lb/ft³
• Darcy friction factor ($f$): 0.02 (assumed)
• Pressure drop ($\Delta P$) from 40 PSI to atmospheric pressure: 40 PSI - 14.7 PSI = 25.3 PSI

Now, let's plug these values into the Darcy-Weisbach equation to find the flow velocity ($V$):

V=f×L×ρ2×ΔP×D​

​

V=0.02×220×62.42×25.3×0.125​

​

V≈27.4566.325​

​

V≈0.23

​

$V\approx 0.479\text{ft/s}$

Now, we can calculate the flow rate ($Q$) using the formula:

$Q=A\times V$

Where $A$ is the cross-sectional area of the pipe. The cross-sectional area of a pipe with diameter $D$ is:

A=π×(2D​)2

A=π×(20.125​)2

$A=\pi \times 0.0625$

$A\approx 0.1963\text{square feet}$

Now, we can calculate the flow rate:

$Q=0.1963\times 0.479$

$Q\approx 0.094\text{cubic feet per second (cfs)}$

To convert cubic feet per second to gallons per minute, we need to multiply by a conversion factor. Since 1 cubic foot per second is approximately 448.831 gallons per minute, we'll use that conversion factor:

$Q\approx 0.094\times 448.831$

$Q\approx 42.285\text{GPM}$

So, approximately 42.285 gallons per minute will flow from the 1.5" copper pipe at 40 PSI with the given conditions.

Another site had around 85.

We're actually doing this math now, expanding and adding a brewhouse. The engineers are insisting we add a city water buffer tank, as the new house will probably consume more than we can supply (even with a 2" line at like 90psi lol). A buffer tank and a pump may be the way your buddy needs to go too.

Hi Craig, they have 40 psig coming into the building.

What pressure do you have coming in from the city, in that 1.5" line?

I did some math with a few online calculators, and I'm getting varied results:

"40PSI at 1.5" = 110 GPM maximum capacity"

(https://resources.hy-techroof.com/blog/how-much-water-can-flow-through-a-pipe)

ChatGPT spit out this gem:

To determine the flow rate in gallons per minute (GPM), we need to solve for the flow velocity ($V$) using the Darcy-Weisbach equation and then use the cross-sectional area of the pipe to calculate the flow rate.

Given the parameters provided:

• Equivalent length of the pipe ($L$): 220 feet
• Pipe diameter ($D$): 0.125 feet (1.5 inches)
• Density of water ($\rho$): 62.4 lb/ft³
• Darcy friction factor ($f$): 0.02 (assumed)
• Pressure drop ($\Delta P$) from 40 PSI to atmospheric pressure: 40 PSI - 14.7 PSI = 25.3 PSI

Now, let's plug these values into the Darcy-Weisbach equation to find the flow velocity ($V$):

V=f×L×ρ2×ΔP×D​

​

V=0.02×220×62.42×25.3×0.125​

​

V≈27.4566.325​

​

V≈0.23

​

$V\approx 0.479\text{ft/s}$

Now, we can calculate the flow rate ($Q$) using the formula:

$Q=A\times V$

Where $A$ is the cross-sectional area of the pipe. The cross-sectional area of a pipe with diameter $D$ is:

A=π×(2D​)2

A=π×(20.125​)2

$A=\pi \times 0.0625$

$A\approx 0.1963\text{square feet}$

Now, we can calculate the flow rate:

$Q=0.1963\times 0.479$

$Q\approx 0.094\text{cubic feet per second (cfs)}$

To convert cubic feet per second to gallons per minute, we need to multiply by a conversion factor. Since 1 cubic foot per second is approximately 448.831 gallons per minute, we'll use that conversion factor:

$Q\approx 0.094\times 448.831$

$Q\approx 42.285\text{GPM}$

So, approximately 42.285 gallons per minute will flow from the 1.5" copper pipe at 40 PSI with the given conditions.

Another site had around 85.

We're actually doing this math now, expanding and adding a brewhouse. The engineers are insisting we add a city water buffer tank, as the new house will probably consume more than we can supply (even with a 2" line at like 90psi lol). A buffer tank and a pump may be the way your buddy needs to go too.

Hi Craig, they have 40 psig coming into the building.