InfoWorks TS (Transient Systems) is part of the world’s premier transient analysis and modeling software for water distribution systems. InfoWorks TS provides you with the most advanced and comprehensive platform available for analyzing complex hydraulic transients with incredible power, speed and ease of use.
Transients in water distribution systems are a major concern for pipeline analysis, design and operation as they have the potential to wreck or damage pipeline systems and equipment, reduce system efficiency, induce adverse water quality conditions, and threaten the integrity and quality of supply as well as public safety.
Pressure surges (waterhammer) developed during startup and shutdown, and/or under accident conditions such as loss of power to the pumps or inadvertent valve closure, may exceed (steady-state) design values. Cavitation or excessive pressure surging during transient operation can lead to pipeline or component failure. Surge control devices are often required to prevent the development of such conditions. The proper selection and evaluation of these devices requires a reliable transient flow analysis. Surge analysis is a vital task (and should be included) in the design of water distribution systems to ensure safety and reliability under emergency conditions.
InfoWorks TS represents the state-of-the-art in water supply and distribution systems transient analysis. Each program provides scores of advanced pressure surge simulation capabilities for analyzing mission-critical transient events, including cavitation and various commonly employed surge suppression/protection devices such as open surge tanks, closed surge tanks, discharge tanks, pressure relief valves, surge anticipation valves, air release/vacuum valves, flywheels and pump bypass lines. Vapor cavitation and liquid column separation are explicitly modeled, allowing the effect of pressure surges due to vapor cavity collapse to be properly evaluated. InfoWorks TS also utilizes the full four quadrant pump characteristics in addition to using the moment of inertia of the moving pump parts to compute pump rundown speeds. This approach is essential for modeling situations where abnormal pump operation occurs such as turbining, flow and speed reversal, etc.
Unique Real-Time Transient Analysis Functionality
InfoWorks TS introduces advanced, user-driven real-time functionality that gives engineers the unprecedented ability to step through an extended period dynamic simulation (EPS); select desired critical time (e.g., peak hour); and launch a precise surge analysis with automatic calculation of all active boundary conditions at the selected time instant, such as tank levels, pump and value settings and status, and demands. This unique, essential functionality allows engineers to successfully build and optimize truly representative models of their water distribution systems in record time and with greater confidence. It also enables water utilities to quickly and reliably identify the critical operational time that will result in the most severe transient conditions in their distribution systems. With this information, they can more accurately predict the development of unacceptable operating conditions in their distribution systems, identify risks, formulate and evaluate sound protective measures, and determine improved operational plans and security upgrades.
Unique Contaminant Intrusion Calculation
An objectionably low-pressure transient event, arising for example from a power failure or from an intermittent/interrupted supply, has the potential to cause the harmful intrusion of untreated, possibly contaminated groundwater into pipes with leaky joints or cracks as the risk of backflow increases significantly with reduced pressure. This is especially important in systems with pipes below the water table. Pathogens or chemicals in close proximity to the pipe can become a potential contamination source. In the event of a large intrusion of pathogens, the chlorine residual normally sustained in drinking water distribution systems may be insufficient to disinfect contaminated water, which can lead to damaging health effects.
InfoWorks TS automatically calculates the volume of intrusion due to objectionably low or negative system pressures. This will help you determine the extent of contamination and evaluate the most effective response strategies.
Trust a Proven State-of-the-Art Methodology
InfoWorks TS utilizes the powerful Wave Characteristic Method (WCM), a hybrid (and improved) version of both the Wave Plan Method (Lagrangian) and the Method of Characteristics (Eulerian), which is unquestionably the fastest, most efficient, most rigorous, most robust and stable algorithm for solving hydraulic transients.
The main drawbacks of the Method of Characteristics are that the time step used in the solution must be common (fixed) to all pipes, and that the distance step in each pipe must be a fixed multiple of the common time interval (further complicating the solution procedure and compromising accuracy). In practice, pipes tend to have arbitrary lengths and it is seldom possible to satisfy exactly both the time interval and distance step criteria. This "discretization problem" requires the use of either interpolation procedures (which have undesirable numerical properties) or distortions of the physical problem (which introduces an error of unknown magnitude). In addition in order to satisfy stability criteria (Courant condition) and ensure convergence, the Method of Characteristics requires a small time step thus resulting in very long execution times. Finally, the Method of Characteristics requires calculations to be made at all interior grid points but it extrapolates the elevation for these interior points from the end nodes, and thus, may inaccurately calculate conditions at those points.
The main advantage of the Lagrangian Wave Characteristic Method is that is solves the transient problem in an event-oriented system simulation framework. This award-winning technology results in improved stability and computational efficiency, allowing very large systems to be solved in an expeditious manner (a 2,000 pipe network can be solved in less than 20 seconds!). WCM thus makes it possible for transient modeling that is less sensitive to the structure of the network and to the length of the simulation process itself. Both MOC and WCM will virtually always produce the same results, the main difference is in the number of calculations where the WCM has a significant advantage.
To illustrate the computational advantage of WCM vs MOC, consider a water distribution system of 2,000 pipes (1,500 nodes) with a total pipe length of 100 miles. The WCM will require 3,500 calculations each time step regardless of the specified accuracy of the model. The number of calculations required for the MOC depends on the accuracy, and an accuracy of only 50 feet (model lengths vs actual lengths) will require around 21,500 calculations per time step. In many cases, it is important to use greater accuracy to accurately model short pipe lengths. For a 10 foot accuracy the MOC will require over 210,000 calculations per time step. The time step required will be around 0.0025 seconds or 400 steps for each second of simulation. A 2 minute simulation will require around 480,000 time steps so the math shows the very extreme demands on the traditional MOC approach. Click here to perform your own live comparison between the two methods.
American Water Works Association Research Foundation (AWWARF) Trusted Technology
AWWARF relied on the powerful WCM to verify surge modeling of low pressure events and distribution system intrusion using both field testing and laboratory testing – Good agreement was obtained.
AWWARF Project #436 – Pathogen Intrusion Into the Distribution System.
AWWARF Project #2686 – Field Testing of Surge Modeling Predictions to Verify Occurrence of Distribution System Intrusion.
AWWARF Project #2580 – Surge Modeling and Field Data Comparisons for a Large Water Distribution System.
InfoWorks TS generates comprehensive results for pressure head and flow variations for all positions in the water distribution system in addition to gas volumes for closed surge tanks and air vacuum valves and pump speed variations for pump trips. Both tabular and graphical reporting capabilities are fully supported. These capabilities will allow the user to determine system's response to pump station power failures, valve closures, and pump speed changes, as well as assess the relative merits of various surge protection measures to reduce leaks, avoid breaks, investigate control actions and strategies, and improve water quality in the distribution system.
InfoWorks TS can help water utilities design and operate their systems with greater reliability and safety by avoiding the potential catastrophic effects of waterhammer and other undesirable system transients.
InfoWorks TS Delivers Unprecedented Power for Managing:
|• Pump Operations|
|• Shut Downs|
|• Start Ups|
|• Pump Trips (Power Loss)|
|• Hydrant Operations|
|• Valve Operations|
|• Tank Operations|
|• Surge Protection|
|• Air Release|
|• Vacuum Breakers|
|• 1/2/3 Stage Air Valves|
|• Surge Vessels|
|• Open Surge Tanks|
|• Closed Surge Tanks|
|• Stand Pipes|
|• Bladder Tanks|
|• Bypass lines|
|• Surge Anticipation Valves|
|• Valve Stroking|
|• Check Valve Action|
|• Low Pressure|
|• Pathogen Intrusion|
|• Water Quality Crisis Events|
|• System Reliability and Integrity|
|• Leakage Detection and Control|
|• Pressure Dependent (Sensitive) Demands|
|• Pressure Relief Valves|
1Reprinted from Journal AWWA, Vol. 97, No. 5 (May 2005), by permission. Copyright © 2005, American Water Works Association.
2Reprinted from Journal AWWA, Vol. 97, No. 7 (July 2005), by permission. Copyright © 2005, American Water Works Association.
3Reprinted from Journal AWWA, Vol. 99, No. 1 (January 2007), by permission. Copyright © 2007, American ater Works Association.
4Reprinted from Journal AWWA, Vol. 99, No. 12 (December 2007), by permission. Copyright © 2007, American Water Works Association.
5Reprinted from Journal AWWA, Vol. 101, No. 2 (February 2009), by permission. Copyright © 2009, American Water Works Association.
6Reprinted from Journal AWWA, Vol. 101, No. 4 (April 2009), by permission. Copyright © 2009, American Water Works Association.
7Reprinted from Journal AWWA, Vol. 101, No. 6 (June 2009), by permission. Copyright © 2009, American Water Works Association.