by

Ph.D. Candidate Shan-Bin Xie

Dr. Yu-Wen Zhou

Beijing University of Technology

An Event Driven Model Framework for Water

Distribution Systems Based on Transient Flow

Analysis

Thanks to

Institute for Mathematical Sciences

Singapore - Delft Water Alliance

Tropical Marine Science Institute

Pacific Institute for Mathematical Sciences

Contents

Introduction & Background Object-Orient Framework Design for

Pipelines System Water Demand Assessment Transient Flow Analysis Event Model for Pipelines System Conclusion Discussion

Water Distribution System Analysis Model

Steady-State Analysis All water demands and operations are treated as constant over

time and a single solution is generated

Extended-Period Analysis Variations in water demands, tank water levels, and other

operational conditions are simulated by a series of steady-state analyses that are linked together.It introduce some approximations and ignores the transient phenomena resulting

from sudden changes

Introduction & Background

Water Distribution System Analysis Model

Water Quality Analysis It predict the temporal and spatial distribution of a variety of

constituents within a distribution system, these constituents include: The age of water, chemical compound such as chloride or fluoride etc.

Transient Flow Analysis It simulates sudden changes of pipelines system’s

component,such as pump shut off & speed adjustment,valve suddenly close,etc

Introduction & Background

Research Aims

Construct unified model framework to be reused in developing applications

Develop a model integrating transient analysis for simulating water hammer with Extended-Period Analysis to help utility’s operator in water distribution system’s management

Introduction & Background

Object-Orient Framework Design for Pipelines System

Element Hierarchy Structure

Element Hierarchy Structure

Element

Node Link

JunctionTank

Reservior

Pipe PumpValve

Object-Orient Framework Design for Pipelines System

Handler Hierarchy Structure

Handler Hierarchy Structure

Handler

Hydraulic Analysis

Quality Analysis

Steady Analysis

Dynamic Analysis

Gradient Method

Mehtod of Wave Plan Mehtod

Method of Characteristics

Optimization Algorithm Set

Calibration Analysis

Object-Orient Framework Design for Pipelines System

System Framework System Framework

Element

Handler

Network

1..n

1

1..n

1

Task

1..n

1

1..n

1

1..n

1

1..n

1

Data Source

Task Manager

Handler Factory

Network Factory

Configuration

1..n

1

1..n

1

1..n1 1..n1

1

1..n

1

1..n

1

1..n

1

1..n

Water Demands Assessment

0

1000

2000

3000

4000

5000

6000

7000

8000

1 3 5 7 9 11 13 15 17 19 21 23

h时间（ ）

m用水量（

3 ）

050510 050710 051010 051210 060210

0

1

2

3

4

5

6

7

1 3 5 7 9 11 13 15 17 19 21 23(h)时间

(%)

用水量系数

冬季 夏季

Difference SeasonDemand Variation

Difference SeasonDemand Variation

Difference MonthDemand Variation

Difference MonthDemand Variation

System demands vary over the course of months & seasons

Water Demands Assessment

R2 = 0. 7852

90

92

94

96

98

100

102

104

051229 051231 060102 060104 060106

d时间（ ）

10用水量（

3 m3 ）Weekend Water DemandWeekend Water Demand

Holiday (New Year) Water Demand

Holiday (New Year) Water Demand

In particular day

Water Demands Assessment

0. 00. 10. 20. 30. 40. 50. 60. 70. 80. 91. 0

0 2 4 6 8 10 12 14 16 18 20 22

t(h)

用水量系数

0. 0

0. 1

0. 2

0. 3

0. 4

0. 50. 6

0. 7

0. 8

0. 9

1. 0

0 2 4 6 8 10 12 14 16 18 20 22

t(h)

用水量系数

0. 0

0. 1

0. 2

0. 3

0. 4

0. 50. 6

0. 7

0. 8

0. 9

1. 0

0 2 4 6 8 10 12 14 16 18 20 22

t(h)

用水量系数

Beijing JingNan xianshuigu

0. 0

0. 1

0. 2

0. 3

0. 4

0. 5

0. 6

0. 7

0. 8

0. 9

1. 0

0 2 4 6 8 10 12 14 16 18 20 22t(h)

用水量系数

0. 0

0. 1

0. 2

0. 3

0. 4

0. 5

0. 6

0. 7

0. 8

0. 9

1. 0

0 2 4 6 8 10 12 14 16 18 20 22t(h)

用水量系数

0. 00. 10. 20. 30. 40. 50. 60. 70. 80. 91. 0

0 2 4 6 8 10 12 14 16 18 20 22

t(h)

用水量系数

2

0

1

1

N

i

s x i xN

Tendency item +Periodic item

Random item

Demand Decompositio

n

Water Demands Assessment Demand Variation & Pattern Cluster Analysis

Demand Spatial Distribution Bill Database & Base Demand Assessment (GIS) Unmeasured Demand Assessment &

Demand Balance Real-Time Demand Assessment temporal downscale & Optimization Algorithm (SCADA:

Supervisory Control and Data Acquisition) Integrated Demand Analysis Framework Business Intelligence (MS SQL 2005 analysis service)

Water Demands Assessment

0

2

4

6

8

1 3 5 7 9 11 13 15 17 19 21 23

时间（小时）

%小时用水百分率（）

Demo Town: xianshuigu

Domestic Demand Pattern

Water Demands AssessmentDemo Town: xianshuigu

1 4

7

10

13

16

19

22

金融

商业

医院餐饮0

5

10

15

20

小时用水百分率%

（）

时间（小时）

金融工业洗浴商业企业限时供水医院服务宾馆餐饮

Diverse Categories Demand Pattern

Water Demands AssessmentDemo Town: xianshuigu

Head Contour Graph

Transient Flow Analysis

1

2

2

| | 0 (1)2

0 (2)

x t

t x

fL gH V V V

D

aL H V

g

| | 02

| | 02

g dH dV fV V

a dt dt D Cdx

adt

g dH dV fV V

a dt dt D Cdx

adt

Basic Governing Equation

Transient Flow Analysis

Characteristic Lines in X-T Plane

Transient Flow Analysis

In which

)4(

)3(

PMMP

PPPP

QBCHC

QBCHC

gA

aB

QRBB

QRBQHC

QRBB

QRBQHC

BM

BBBM

AP

AAAP

)8(

)7()]1([

)6(

)5()]1([

Transient Flow Analysis

Characteristics at Boundary

Transient Flow AnalysisWave Speed Calculation Fluid compressibility & pipe flexibility

Wall shear stress models

Numerical scheme

Flow stability & axisymmetric assumption

Complex boundary condition

Event Model for Pipelines System

Event Type：HitTest; Strategy(simple, complex (auto controlling decision made)?)

Event Pool： Arraylist or Hashtable

( Task type private member, Task owns a pair register/unregister method, event can be automaticly registered/unregistered to a task )

Event &Event Model

Event Prototype: delegate void EventName（ Element sender, TransientEventArgs e ）

TransientEventArgs member: StartTime, Duration, ControlledParameter, ParameterTimeSerial, TransientOption(TimeStep,FrictionFormulation,DefaultWaveSpeed,etc)

Event Model for Pipelines System

Demo:

Event Model for Pipelines System

Demo: Characteristic profile along selected path

特定管网路径特征线

0

20

40

60

80

100

120

140

160

0 610 1158173722862865338438564374管线距离（米）

高程（米）

管线高程

初始水头

最大水头

最小水头

25秒时水头线90秒时水头线饱和水蒸汽压力线

Event Model for Pipelines System

Demo: Head time series line at selected points

特征点水头过程线

20

40

60

80

100

120

140

0 15 30 45 60 75时间（秒）

水头（米）

水泵出口点水头

36 34：点水头

41 36：点水头

Construct unified model framework to be reused in developing applications

Encapsulate transient analysis with event model and simplify model architecture

Conclusion

Small temporal scales and accurate SCADA data can be helpful to evaluate the system’s state, Downscale & SCADA data analysis technique may be useful and important.

How to automatic instance an event & trigger it? How to instance a complex strategy type event

according to pipelines system’s state & utility’s management strategy? Maybe use optimization algorithms? There maybe another method? Sincerely ask for help!

How to integrate Automatic Control Theory in investigating of inverse problem (such as system’s exceptions identity & handling, etc) in pipelines system?

Discussion

Thank you for your attention.

Shanbin XieEmail: cnwaterworker@yahoo.com.cn

Data-driven and Physically-based Models for Characterization of Processes in Hydrology, Hydraulics, Oceanography and Climate Change6 - 28 Jan 2008

THE END