Operating speed changes for pumps produces transients. A time dependent change in the speed ratio(s) (operating speed/rated speed) may be defined for all types of pumps. A ratio of 1 means the pump is working with the full speed and 0 implies the pump is stopped). The procedure below describes how to assign a curve to a pump:
-
Click on the Select Menu
button of the Attribute Browser window, and then click on the Select Pump
button and select the desired pump in the map window. -
Click on the Pump Operation Change
button from the Surge toolbar. The Pump Operation Change Data dialog box appears on the screen. -
If no Pump Surge Data has been entered, the only Disturbance Type available for selection is "0:Speed". You can choose either an existing Speed Curve from the drop-down list or click on the Browse
button to the right to create a new curve or edit an existing one. The Pump Speed Curve contains a curve of the pump speed factor over the time of the simulation. -
If it is necessary to install a bypass line and/or a check valve with the pump, click on the Pump Surge Data
button to access the Pump Surge Data dialog box.
Example - The pump is running at full speed (1.0) for 2 seconds and then the speed ramps down to half over the next 2 seconds.
