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H2OSURGE (FULLY INTEGRATED with AutoCAD 2002-2009 and H2ONET), InfoSurge (FULLY INTEGRATED with ArcGIS 8.x/9.x and InfoWater) and H2OMAP Surge (FULLY INTEGRATED with H2OMAP Water) are the world’s
premier transient analysis and modeling software
for water distribution systems. Only
H2OSURGE/InfoSurge
seamlessly integrate AND seamlessly interface
with your existing AutoCAD and ArcGIS projects to
provide you with the most advanced and comprehensive
CAD and GIS platform available for analyzing complex
hydraulic transients with incredible power, speed
and ease of use. H2OSURGE/InfoSurge can
also automatically and accurately import
(and export) any EPANET file and can model the complete
library of hydraulic components and surge protection/anticipation
devices.
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.
H2OSURGE/InfoSurge/H2OMAP Surge represent 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.
H2OSURGE/InfoSurge/H2OMAP Surge also utilize 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
H2OSURGE/InfoSurge/H2OMAP Surge introduce 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 (that mimics
SCADA measurements) 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 within
the powerful CAD and GIS environments 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
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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.
H2OSURGE/InfoSurge/H2OMAP Surge automatically calculate
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
H2OSURGE/InfoSurge/H2OMAP Surge utilize 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. Developed originally for NASA,
the Wave Characteristic Method is similar to the
industry/USEPA standard Lagrangian Time-Driven Method
(TDM) for dynamic water quality modeling (used by
EPANET 2.x) and calculates
results along the pipelines (including low and high
points), at junctions, and network components. It
is the Lagrangian nature of TDM that makes the water
quality calculations in EPANET Version 2.x about
10 to 14 times faster than the Eulerian DVM used
in EPANET Version 1.x, while producing similar results.
The main drawbacks of the Method of Characteristics
(similar to the Eulerian Discrete Volume Method
for dynamic water quality modeling used by EPANET
1.1x) 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.
And with
thousands of projects worldwide, H2OSURGE/InfoSurge's
unrivalled computational engine has been successfully
used by many of the largest cities to accurately
analyze some of the most complex systems.
H2OSURGE/InfoSurge/H2OMAP Surge generate 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.
H2OSURGE/InfoSurge/H2OMAP Surge 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.
H2OSURGE/InfoSurge/H2OMAP Surge Deliver Unprecedented
Power for Managing:
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Pump
Operations |
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Shut
Downs |
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Start
Ups |
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Pump
Trips (Power Loss) |
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Hydrant
Operations |
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Valve
Operations |
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Tank
Operations |
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Surge
Protection |
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Air
Release |
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Vacuum
Breakers |
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1/2/3
Stage Air Valves |
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Surge
Vessels |
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Open
Surge Tanks |
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Closed
Surge Tanks |
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Stand
Pipes |
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Bladder
Tanks |
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Flywheel |
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Bypass
lines |
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Surge
Anticipation Valves |
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Valve
Stroking |
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Check
Valve Action |
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Low
Pressure |
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Pathogen
Intrusion |
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Water
Quality Crisis Events |
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System
Reliability and Integrity |
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Leakage
Detection and Control |
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Pressure
Dependent (Sensitive) Demands |
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Pressure
Relief Valves |
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And many more.
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
Water Works Association.
4Reprinted from Journal AWWA,
Vol. 99, No. 12 (December 2007), by permission.
Copyright © 2007, American Water Works Association.
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