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Can I model fluids other than Water?
Yes, and the steps below describe how to do this. Please note that only Newtonian liquids are valid, and you might need to adjust your pump definitions if the viscosity of your fluid differs from water. Furthermore, as Hazen-Williams friction method is an empirically based formula, its calculated friction losses are only applicable to Water @ 20 deg C. It should not be used for other liquid types (and you should use Darcy-Weisbach instead).
1) Go to Analysis > Calculation Options and click on the calculation option that you'll be using for this analysis to access the properties
2) Go to the Hydraulics section towards the bottom of the properties window and click the ellipsis button on the right side of the liquid label cell as seen below.
3) This opens the Liquid Libraries for the Engineering Library and you can select the liquid that you'd like to use from there. Note that on the right hand side of the window the liquid properties like Kinematic Viscocity, temperature, Vapor Pressure, and the bulk modulus of elasticity are displayed.
4) After you create or decide on one of these use the select button to choose that liquid.
5) If you'd like to create a new liquid with different characteristics go to Components > Engineering Libraries and expand the liquid library. Left click on the 'Liquid library.xml' label as shown in the screen shot below and then click the 'Add Item' option. Finally, enter your data and name the new liquid. Click close when done.
Note that only one liquid temperature can be set for a given simulation run. This is notable in a case where you have a significant change in temperature in the network being analyzed, such as for a heat supply network. From the HAMMER Help topic “Bentley HAMMER V8i Theory and Practice”,
With Bentley HAMMER V8i, you can analyze drinking water systems, sewage forcemains, fire protection systems, well pumps, and raw-water transmission lines. You can change the specific gravity of the fluid to model oil or slurries, for example. Bentley HAMMER V8i assumes that changes in other fluid properties, such as temperature, are negligible. It does not currently model fluids with significant thermal variations, such as can occur in cogeneration or industrial systems.
So, unless you can make a valid, conservative assumption, then the transient results may be skewed if you have a significant change in temperature. One approach is to try a sensitivity analysis: do several model runs, varying the liquid properties for multiple temperatures. If there’s no notable difference in transient response, then you might conclude that HAMMER can model their situation OK.
Or, if there is a clear separation between the segments of the network at two different temperatures, you may be able to do two separate model runs.