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Thread: Water temperature

  1. #1
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    Water temperature

    InfoWater has the option to simulate water temperature (in water quality). However, it provide no information about the algorithm of data input.
    What are the physical principles used to simulate temperature?
    Where do I enter the data?
    Is there an example?

  2. #2
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    Innovyze Employee



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    Vladimir,

    The Temperature option under the Quality Tab of the Simulation options with the Chemical/Temp Option selected and the "Temperature Modeling" checkbox selected provides a very basic temperature analysis. As far as I can tell from running a few tests is that it essentially treats temperature as a conservative substance and disables the bulk and pipe decay coefficients. Like any Quality analysis the Initial Water quality values would be “temperature” as well as any Water Quality source settings assigned to a model element. Since it treats temperature like a conservative substance the model is simply calculating “temperature” at model locations based on simple mixing rules and the temperature of the water coming in to a junction. But this analysis does not have temperature grow or change except by mixing with other temperature sources.
    Simulation Options Quality Tab – Chemical/Temp Option Selected + Temperature option
    (click if need larger image)

    Simulation Options-Temperature Modeling + Help.jpg

    I have included the definitions of the elements needed in the help file.

    However, if a user has access to an InfoWater MSX license (multi-species) (link for further information: http://innovyze.com/products/infowater/#msx ) the user can do a much more in depth Temperature analysis. This analysis actually can account for heat exchange between the pipes and the ambient environment. Formulas for temperature MSX analysis are already assigned in the MSX Module. This MSX Temperature model is quite general and can model the temperature change of pipe water under the influence of ambient temperature, wall material, flow condition, buried depth, etc. Complete mixing is still assumed as in other water quality models. Ambient temperatures can be described either as a time pattern. The user just has to create a pattern called "PATTERN_AMBTEMP" that defines how the system ambient outside temperature TA varies over an EPS timeframe to use this MSX Temperature analysis.

    Details of the MSX extension as well as a quick start tutorial on the MSX features can be found in the InfoWater User Guide found here:
    In the Start->Programs -> Innovyze-> InfoWater menu open the InfoWater User Guide
    Or you can browse to this directory: C:\Program Files(x86)\InfoWater\Help\InfoWater Users Guide.pdf (or Water.pdf)

    Details of the Temperature Analysis MSX Formulas used can be found on page 4-60 through 4-62 of the User Guide
    An MSX example Model can be found in the C:\Users\Public\Documents\InfoWater\Examples in the Net3MSXSol Exercise 1.mxd model.

    If you create the "PATTERN_AMBTEMP" pattern to model how the ambient temperature fluctuates over a 24 hour period and set the MSX model to TEMPERATURE in this example you can run a temperature analysis.

    How to set the simulation options for an MSX Temperature Analysis (Requires an active MSX license)
    (click if need larger image)
    simulation options - MSX Temp Analysis.png

    Hope this helps understand the two ways to run a temperature analysis in InfoWater.

    Patrick Moore

  3. #3
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    Dec 2016
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    Thank you.

    One question. How do I apply a constant initial temperature?
    The first time step I get one temperature (about 27 C), but from the second time step and the other it goes to 0. How can I get an initien temperature at a given source node?

  4. #4
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    Innovyze Employee



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    Vladimir,

    Assign a constant source "temperature" the same way you would assign a constant WQ source like you asked in a different thread. Temperature is modeled as a constituent, so to make it constant, set it up just like a constituent. But I would use a reservoir source instead of a negative demand if you are not. Reservoirs are much better in EPANET as quality sources than anything else.

    Here is what I posted in the other thread regarding a chlorine source. Use the same method to assign a "temperature" WQ source.

    Your Question:*When simulating water quality chlorine, how do I enter the concentration source?
    Innovyze Response:
    To specify a continual water quality source at a reservoir one should both specify an Initial Water Quality for the Reservoir as well as assign a quality source in the “hammer menu” of the model explorer with that reservoir as the active element. Specifying a concentration Type and a baseline concentration will maintain that concentration for all water leaving the reservoir but will not specify the initial Water Quality so specify both to seethe desired concentration over the entire analysis period. If desired you can also specify a pattern to vary the quality over time. If the concentration is constant leave the pattern field blank. Generally you define WQ sources on Model Reservoirs as these are the true water "sources" in your model. It is much preferred to use a reservoir and a device to control water supply than using a negative demand when doing a chlorine analysis as quality sources on junctions can act unusual. The reservoir method will always work as expected.

    Defining a quality source for a reservoir
    (click if need larger image)
    Defining a quality source.png


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