I am not able to see maximum volume of gas in the Transient Analysis Output Log (Under Report > Transient Analysis Reports)

Hello Dinesh,

In the "Analysis Output Log" under Analysis > (in the Transient tab) Analysis Output Log, you can find the maximum and minimum gas volumes below the "Snapshot of Every End Point" table. Just search (CRTL + F) for the term "maximum" in the report and you will locate the maximum and minimum gas volumes.

Here is a snapshot of the Output Log for a sample model analyzed in HAMMER;

Alternatively when the transient analysis is done, a notification would appear under User Notifications which provides information on the maximum and minimum gas volumes. The message would be in the following format;

"48117 "HT - Without Bladder" "Hydropneumatic Tank" "86" "Hydropneumatic Tank" "The maximum and minimum pressure of gas for all calculation steps are (0.11E+03 m H2O) and (0.28E+02 m H2O), the maximum and minimum volume of gas for all calculation steps are (0.84E+00 m³) and (0.22E+00 m³)." Transient Engine"

In your user notifications tab the message would appear like this;

When the notification is expanded, the message would appear in the above given format.

Here is a reference article for modeling Hydropneumatic Tanks;

Modeling Reference - Hydropneumatic Tanks

Hope this helps.

Thanks. Yashodhan for the quick reply, which is quite helpful.

Another query is does hammer indicate the possible / proposed location for surge protection device ? 

I knew abour transient thematic viewer and colour coding of pipe to check the intensity of various parameters (pressure, air/vapour etc).

Hello Dinesh,

HAMMER analyzes the transients in the system and provides you with the worst conditions in your pipeline as per the event you setup (i.e. pump shutdown, sudden valve closure etc.). The software will analyze these events and calculate the transients produced. By viewing the transient results, one can determine the optimum surge mitigation method to be employed.

You can identify key sections in your pipeline / rising main by observing the negative pressures and vapor volume produced which would lead to extreme pressures which can potentially harm the pressure sustainability of the pipes.

By identifying the key sections of the pipeline, you can try using different surge mitigation methods (air valves, hydro tanks, surge tanks etc.) and test the effectiveness of them in different scenarios.

Ultimately, using the correct surge mitigation equipment is dependent on your engineering judgement as well as the project requirements.

I concur with Yashodhan; transient protection varies greatly for each system, and sometimes it is a combination of multiple devices and strategies. There are also many ways to configure each device, and you may have budget and space constraints.

HAMMER's scenario management feature enables you to easily compare different strategies and arrangements: Viewing HAMMER results for multiple scenarios