• 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…
  • 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…
  • 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 - 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: 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?