Network Pipe Flow: Understanding Assumptions and Calculating Junction Position

• foo9008
In summary, the author made an assumption that the junction is located at 20m from the datum in order to find the correct answer for the flow of water.

Homework Statement

from the diagram , we know that the junction is lower than the pipe at B . why the author want to make an assumption that the junction is located at 20m from the datum ? is it correct to do so ?

The Attempt at a Solution

eventually , i found the ans is 25.2m , the delta Q is close to 0 ,
but , i also tried with 18m , then slowly change to 16m and 14m , by using Q1+Q2 - Q3 , i found the ans is getting bigger , does it mean the junction has to be higher? [/B]

P/s : to admin , hopefully , i moved to an appropriate place to get better response

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Yes, it does mean that the junction has to be higher. This is because when the junction is lower than the pipe at B, the flow of water will increase with the increasing height of the junction. So, if we assume the junction is located at 20m from the datum, then the flow of water will be greater than if the junction was located lower. Thus, the answer you found (25.2m) is correct.

1. What is flow in a network of pipes?

Flow in a network of pipes refers to the movement of a fluid, such as water or gas, through a system of interconnected pipes. It is typically measured in units of volume per unit time, such as cubic meters per second or gallons per minute.

2. How is flow in a network of pipes calculated?

The calculation of flow in a network of pipes involves several factors, including the diameter and length of the pipes, the type of fluid being transported, and the pressure and velocity of the fluid. It can be determined using various equations, such as the Bernoulli's equation or the Darcy-Weisbach equation.

3. What factors affect flow in a network of pipes?

Several factors can affect the flow in a network of pipes, including the diameter and roughness of the pipes, the viscosity and density of the fluid, and the overall design and layout of the system. Changes in these factors can result in variations in flow rate and pressure within the network.

4. How is flow in a network of pipes controlled or regulated?

Flow in a network of pipes can be controlled or regulated through the use of valves, pumps, and other flow control devices. These can be manually operated or automated, and are designed to adjust the flow rate and direction of the fluid within the network.

5. What are some applications of flow in a network of pipes?

Flow in a network of pipes is used in various industries and applications, including water distribution and treatment systems, oil and gas pipelines, heating and cooling systems, and transportation of chemicals and other fluids. It is also essential in the functioning of household plumbing and irrigation systems.