However during its actual operation, the pump may provide a different flow rate (considering we will not be throttling any discharge valves). The rated capacity of the pump has been defined as 20 m³/hr. However, the first thing that we need to concentrate on is the pump itself. We need to find the flow through the pipes AB and AC.
![changing pipe length watergems changing pipe length watergems](https://communities.bentley.com/resized-image/__size/550x400/__key/communityserver-wikis-components-files/00-00-00-00-32/pastedimage1554272703890v2.png)
We are going to consider the pump to be of constant speed type (not VFD driven) to make things a bit more complex (also generally in India we commonly have to deal with constant speed pumps).
![changing pipe length watergems changing pipe length watergems](https://communities.bentley.com/resized-image/__size/940x0/__key/communityserver-discussions-components-files/5925/5314.2.png)
This is a very common system which we often have to deal with. Both the discharge points are discharging to atmosphere (into a tank with the inlet pipe above the top water level of the tank). The pump (P) is pumping water from a reservoir (R) to two discharge points (B and C). After doing so we will compare our results by modelling the same system in WaterGems and try to find if our manually derived results are correct.Ĭonsider the system depicted above. However in this article we are going to look into solving such a system manually without the aid of a network modelling software. Generally for estimating the flows through branched networks we end up using hydraulic network modelling softwares like Bentley WaterGems, EPANET, KYPipe etc. We will be using a result oriented approach by solving a working model of a system. In certain situations it may become extremely important to estimate the actual flows through each branch so as to ensure that the required demands at all the discharge points are truly being fulfilled. However, in reality, that may not always be the case.
![changing pipe length watergems changing pipe length watergems](https://communities.bentley.com/resized-image/__size/940x0/__key/communityserver-wikis-components-files/00-00-00-00-32/lineweight.png)
Generally while creating our P&I diagrams we often tend to estimate the pipe sizes for such a network by considering the flow to be distributed equally in all the branches. We often have to deal with multi-branched pumping schemes where a single pump delivers fluid to more than one location at the same time.