Hydraulic Modeling of Central Heating Network

[HumanistEngineer]

In this task of mine, I need to develop a tool/software to carry out (dynamic) hydraulic analysis of a central heating network, formed with supply and return pipes so forming a multi-parallel loops in a closed circuit, as can be seen in the below picture.

Can anyone suggest me some references especially for the hydraulics of closed circuits? I found some articles describing the graph-theory but I couldn't understand them since they are not mentioning looped formation (Fig 2 - Below Picture). Considering a large scale central heating network, such as District Heating (DH), I need to build a graphical interface together with some generic algorithm (such as in graph theory) that can handle hydraulic analysis (pressure distribution through the whole network).

 

[anorlunda]

I thought you were asking about an ordinary time domain simulation, but when you mention genetic algorithm that implies optimization to me so I'm confused

We have been making simulations of thermal-hydraulic systems since the early 1950s. The equations are the differential equations of first principles, mass balance, energy balance, volume balance, momentum balance, plus heat transfers across boundaries. Is that what you are asking about?

 

[HumanistEngineer]

I thought you were asking about an ordinary time domain simulation, but when you mention genetic algorithm that implies optimization to me so I'm confused

We have been making simulations of thermal-hydraulic systems since the early 1950s. The equations are the differential equations of first principles, mass balance, energy balance, volume balance, momentum balance, plus heat transfers across boundaries. Is that what you are asking about?

Sorry for my poor description. I need to model the network, as you indicated, in an ordinary time domain simulation (the demand/flow rate will change and I will see the pressure distribution through the network - to evaluate if the pressure difference across each end-user station is enough or not). In a further study, I will develop the thermal transients, in detail I will solve the convection-diffusion equation to see the temperature propagation through the network.

I have difficulty to find references about closed-loop networks; especially for this case that all end-user substations are parallel to each other. Since I will deal with modelling of a district heating network -such large scale-, I need a general tool/model that such as in graph theory to evaluate the pressure distribution through the network (such as the one shown in the below picture - ref: Termis(7T)). Can you suggest any reference or tool/code?

 

[russ_watters]

In this task of mine, I need to develop a tool/software to carry out (dynamic) hydraulic analysis of a central heating network, formed with supply and return pipes so forming a multi-parallel loops in a closed circuit, as can be seen in the below picture.

Can anyone suggest me some references especially for the hydraulics of closed circuits? ...

... I need to build a graphical interface together with some generic algorithm (such as in graph theory) that can handle hydraulic analysis (pressure distribution through the whole network).

You're asking for help about writing a hydraulic analysis program from scratch? This seems like an odd request for an internet forum - I would think this is a task a small team of computer and mechanical engineers might spend a year on. Commercially available software for this is highly developed and costs thousands of dollars per license. Is this really what you are asking?

 

[anorlunda]

Commercially available software for this is highly developed and costs thousands of dollars per license.

I'll second that. I wrote such a package in the 70s. The license fee back then was $35K. Alas, it no longer exists, but I'm sure others must. Be patient and some PF member will suggest one.

 

[russ_watters]

Be patient and some PF member will suggest one.

We use this in my office:

https://eng-software.com/products/pipe-flo-professional/

 

[HumanistEngineer]

... I would think this is a task a small team of computer and mechanical engineers might spend a year on. ...

I agree on this but I need to develop in one way the hydraulic model since I need to test a unique new end-user substation so need to evaluate its effect on the DH network. I don't think that we have enough fund for such a commercial software in my project.

Any books, articles etc. that you can suggest for this hydraulic modelling?

 

[anorlunda]

Any books, articles etc. that you can suggest for this hydraulic modelling?

As I said, the equations are pretty elementary, so a paper would not help much. It is the data management, abstract solutions, and iterative methods that make it expensive. How are you at numerical methods, linear algebra, and software engineering?

 

[russ_watters]

I agree on this but I need to develop in one way the hydraulic model since I need to test a unique new end-user substation so need to evaluate its effect on the DH network. I don't think that we have enough fund for such a commercial software in my project.

I expect a commercial license would cost less (and take less time!) than trying to write the software yourself. Alternately you could outsource the analysis task to a company that has the appropriate software. That's what my company does for CFD.