Walk-Through Examples (Metric Units)
The Impulse Walk-through Help System is designed to get new users trained to use Impulse correctly in the shortest amount of time. If this is your first time to use Impulse, start with the Valve Closure - Beginner Example because it is the most complete. After this example, choose an example from the table below that most closely matches your application. The examples are arranged in order of increasing complexity.
Note: The examples in the Help System are available in both English and Metric units. To work these examples in a different unit system, open the appropriate example help file, or click the link to the appropriate unit system example found at the top of each example.
| Example | Fluid | Pipes | Pumps | Description |
|---|---|---|---|---|
| Beginner Valve Closure | Water | 4 | - |
In-depth discussion of model building in AFT Impulse. Solves a simple valve closure problem. |
| Ship to Shore Transfer System - With Cavitation | Ammonia | 3 | - | Three valve closure rates on a fluid transfer system are evaluated with respect to maximum pressure. Cavitation occurs in two cases. |
| Tank Farm - Use of Infinite Pipes | Gasoline | 5 | - | A long supply pipeline flows into a gasoline tank farm. The transient occurs when flow is switched from one storage tank to another. Two scenarios compare the results with and without an infinite pipe boundary, and also compares the run times. |
| Pump Trip With Check Valve | Water | 2 | 1 | A system pumping water uphill loses power to the pump. This model predicts the system response and pump speed decay. |
| Check Valve Modeling | Water | 3 | 1 | A check valve needs to be selected to prevent reverse flow trough a pump in the case of a power failure. Different check valve modeling options are explored. |
| Relief Valve Modeling | Crude Oil | 6 | 1 | A relief valve is considered to reduce pressure in a pipeline after an unplanned valve closure and pump trip. A back pressure relief valve and a rupture disk relief valve are compared. |
| Pump Trip With Accumulator | Water | 3 | 1 | Same system as Pump Trip With Check Valve, except an accumulator is used to minimize the downsurge due to the pump trip to keep all pressures above atmospheric. |
| Pump Startup With Event Transients | Water | 11 | 2 | Transients from different pump startup scenarios are evaluated. A valve opening transient is initiated based on system events. |
| Pump Trip With Backflow - Four Quadrant Modeling | Water | 13 | 2 | Two pumps supplying cooling towers lose power. Valves close, but not before the pumps start to spin backwards. Four-quadrant pump modeling is used to evaluate the pump reaction and system transients. |
| Selecting a Pump Four Quadrant Curve | Water | 9 | 1 | Provides the engineer with a deeper understanding of how to select four quadrant data sets for a waterhammer analysis, and how to evaluate the transient results predicted by the four quadrant curves. |
| Pump With Variable Speed Flow Control | Water | 8 | 1 | A pump with a variable speed drive for flow control supplies water to two heat exchangers. The flow to one of the exchangers is turned off, and the controlled pump flow rate is reduced by half over five seconds. |
| Positive Displacement Pump | Water | 5 | 1 | Models of a duplex and triplex positive displacement pump |
| Valve Closure With Pipe Forces | Water | 2 | - | Determines the transient forces that occur in a gravity drain system that transfers water from one tank to another through a valve in the connecting pipeline. |
