• Hammer results File doesn't contain any transient extended node.

    Hi, I am new to Bentley Hammer. I am analyzing a Gravity pipeline where water will run from 1619 m elevation to 1400 m elevation in a hilly area with ups and downs. When I check " Transient Results Viewer" it gives a dialogue box. "The hammer results…
  • area change modeling

    Hello, how could I model area change in bentley hammer ? Is there any method rather than splitting pipe? does pipe splitting do better simulation for Wave Reflection and Transmission at an expansion and a contraction?
  • Getting reliable results from Bentley Hammer

    Hi, I am modelling a simple system to compare the results to some codes that I have. But, despite having all the configurations similar to codes, I cannot get similar pressure fluctuation. Could you please have a look and let me know the reason? …
  • Modelling a Pelton

    I am modelling a hydro station with 4 pelton units for pressure rise and mass surge. I have currently modelled these as a discharge to atmosphere element as is recommended in the Hammer knowledge base. However, using a discharge-to-atmosphere element…
  • Hammer - Accurate Modelling of a surge Tank

    Hi I am modelling a hydro power station which features an open surge tank. The surge tank is mostly underground and is 7.0 m in diameter, connecting to the main penstock by a 2.5 m diameter, 9.6 m long steel lined pipe which acts as a throttle. My…
  • Hammer V8i - Hydro Power Pump Turbines

    I am currently learning to use this software with the prospect of using it in future projects with clients. Thus far I have modelled standard turbine installations, however I am curious if it is possible to model pump turbines with this software and if…
  • Re: Hammer: Surge Tank Initial Level

    Hi Jesse, thanks for your reply. I do have my tank set up as a junction with no check valve, and as you mention this tank level should follow the HGL. My version is 08.11.03.17 which isn't too old I thought? It seems the steady state isn't accounting…
  • Water Distribution Modeling Software Survey

    Hello, If you have a few minutes please fill out this short survey to help the Bentley Institute Geospatial team create better training that is more suited to the workflow of our users. http://www.surveygizmo.com/s3/568508/Water-Distribution-Modeling…
  • Hammer Protection Device (Help)

    Dear; I am new in using water hammer software. and i have a project which consist of 900 mm transmission line with pump station. I modeled the project for pump shut down due to power failure and i viewed the results for upsurge and downsurge reults…
  • Distribution Sytem Wide Hammer and Transient Analysis of RPZ

    I am attempting to set up a model to demonstrate how a RPZ (Reduced Pressure Principle Backflow Preventer) will respond to Hammer. For those unfamiliar with the operation of an RPZ, I have attached a document which outlines this very well. …
  • Hammer Pump Transient Properties

    Is there anyway to make a responsible assumption for the pump transient properties if accurate data is not available? I have a distribution system model that I've been asked to do some transient analysis for. The model has detailed pump curves but I don…
  • Hammer Negative Pressure - Instability at Steady State

    Hello, I am using Hammer V8i. I have a simple layout for a pump station transient model. A pump draws from a wet well, and discharges over a syphon into an effluent conduit. The discharge syphon creates a negative pressure at steady state. My transient…
  • Re: Hammer: Pelton free-surface tailrace surge

    Hi, thanks for your reply. You are correct; I am looking at the pipe carrying the water away. I have attached a basic sketch. I am modelling the pelton as a TCV followed by a D2A so I can have multi-stage valve control. Typically I would only be interested…
  • Control valve response to transient event

    Is there a way to model the response of a control valve to a transient event beyond manually inputting the transient operational pattern? An example would be what happens to a PSV when the transient pressure drops below the pressure set point.
  • Moment of Inertia Turbine Input - Hammer

    Hi I am trouble shooting a Hammer model of a hydro scheme which is producing unexpected results. I have some confusion around which inertia Hammer uses. For hydro generation applications inertia is usually given as WR2 or GD2, with GD2 being four times…
  • Hammer - Modelling vertical pipes

    I am modelling a hydro scheme which features a vertical shaft directly at the intake. So lets says the intake is J1 at elevation 100m and drops to J2 at 50m by a 50 m length of pipe before completing a 90 degree bend to horizontal. Whe using the profile…
  • Hammer - Turbine Specific Speed Operating Point

    Hi When calculating the turbine specific speed to use in Hammer, is it more accurate to use the values for P, H, Q & n at the turbine best efficient point or rated point? The specific speed for these two operating points will differ. Kind regards
  • Hammer: Turbine Curve in Relation to Quadrant Curve

    Hi I wish to clarify how the Turbine Curve should be sourced for inputting into Hammer in relation to which quadrant curve is being used. I understand the Quadrant curve is defined by the selection of the specific speed. In my case, I am picking a…
  • Hammer: Surge Tank Initial Level

    When modelling a surge tank it is necessary to dictate the initial level. When the steady state conditions are calculated, this seems to not affect the surge tank initial level, even if it does not match the head at the point on the line where it is installed…
  • Hammer Analysis in Raw Water Transmission System

    I'm trying to evaluate the need for surge protection at new well locations in a raw water transmission system. I have a network of 6 wells all pumping to the water treatment plant. I'm new to Water Hammer and surge analysis so I'm just looking for some…
  • Re: Modeling a 1.5 second valve closure at Airplane Fueling Nozzle?

    Hello, The pumps are going to operate based on the system conditions (where the pump curve intersects the system head curve.) So, you'll need to "model what you've got" to get the right pump operating point. Meaning, if there aren't FCVs in reality…
  • Water Hammer Pump Data

    How does Hammer determine the pump speed during a power failure event? It's unclear without the input of the a power curve or torque curve how that data is derived. Are these values interpreted some way from the specific speed? Also, what is the source…
  • Hammer: Pelton free-surface tailrace surge

    Hi I am currently modelling a number of pelton hydro station layouts. One option may (to be confirmed) include a tailrace tunnel with a free surface. Because the tail race tunnel is so long, surges upon start-up are a concern as could flood the pelton…
  • Hammer - Setting gravity

    Hi I am modelling a scheme which has a gravity lower than the standard 9.81 due to elevation. Is there somewhere in Hammer to set this, as surely the available energy will change?
  • General Transient Modeling Help

    Does anyone have a good resource for learning and understanding real world transient problems and models? I'm fairly new to transient analyses but I have been through the Bentley training course. I have a couple transient models that I am currently working…