Good Afternoon!

KATHMANDU UNIVERSITY

SCHOOL OF ENGINEERING

DEPARTMENT OF MECHANICAL ENGINEERING

Project presentation

DEVELOPMENT OF HILL CHART DIAGRAM FOR FRANCIS TURBINE

OF JHIMRUK HYDROPOWER USING COMPUTATIONAL METHOD

Supervised by:DR. HARI PRASAD NEOPANE

MR. KRISHNA PRASAD SHRESTHA

MR. RAVI KOIRALA

By Presented to

MAHESH KANDEL (42086) MR. PRATISTHIT LAL SHRESTHA

PRASHANT NEOPANE (42093) Project coordinator

SUMAN SAPKOTA (42108)

19 JULY 2015

Background: Operational Scenario

overall efficiency of turbine increases with increasing discharge,

reaches maximum at design discharge and then starts decreasing

in part and full load the efficiency drop significantly

Maximum use of energy by minimum energy consumption

Developing technologies advanced simulation technologies

Performance testing prior to turbine manufacturing

Statement of Purpose

Overall Performance (efficiency, discharge, etc.)

Seasonal variation and load fluctuations

A key benefit of CFD is that a great amount of

money can be saved concerning experiments.

A single analyst equipped with a computer, can replace

experimental designing, material costs, measurement

equipment, laboratory personnel etc.

So, CFD Analysis to predict optimized performance

Objectives

Performance analysis of Francis turbine model of Jhimruk

Hydropower

Hill Chart plot by Computational Method

Methodology

Literature Review

Development of theoretical foundations

Computational Analysis

Theory and Literature activity for understanding CFD

Domain modelling, Meshing, Solving CFD problem,

Analysis of Results for performances curve

Hill Chart Plot

Through Matlab by extracting the points from MS

Excel

Methodology: Research and

Development

S/No.Research and

Developmental StageObjectives Methods

1.Development of

theoretical foundations.

To have vision to

understand the

theory behind CFD.

1.1 Literature review

1.2 Discussion and Solving

CFD problem

2.Computer Aided

Simulations

To predict the

performance of the

turbine.

2.1 Theory and Literature

activity for understanding

ANSYS

2.2 CFD Computer

simulation using ANSYS

15 Package

Methodology: Tools used

S/No. Research Tools Objectives Methods

1. CAD (Solidworks)

Designing the Francis

turbine’s domain (Stay

vanes, Guide vanes,

Runner Blades, Draft

tube).

1.1 Importing the

coordinates

1.2 Designing the

components for the same.

2.CFD and CFX

solver

Performance analysis

through simulation

2.1 By using tools and

techniques in ANSYS 15.

3. MS ExcelDetermination of

Performance curves.

3.1 By plotting Graph

between the parameters.

Work Accomplished:

Literature Review

Introduction: Francis Turbine

• Reaction turbine

• Operates in medium head

• Consists of Stay vanes, Guide

vanes , Spiral casing, runner

and draft tube

• Operating condition ranges

from 15 m to 700 m head

Introduction: Jhimruk Francis

Turbine Characteristics

Introduction: CFD

analytical tool to determine the flow behavior, heat transfer, mass

transfer, chemical reactions, etc

Solves equations that governs these processes

Uses numerical method

Solves Navier Stokes equation at the vertex by changing the

governing equations into algebraic equations

Governing equations:

Equation of Continuity

Conservation of Momentum

Conservation of energy

Domain

the area of analysis where the flow of fluid is discretized

and computed

our study consists of stationary (Stay vanes, Guide vanes

and Draft tube) and rotating part (Runner).

CAD modeling

Runner

Stay Vanes Guide Vanes

Draft Tube

Assembled Domain

ANSYS CFX

Introduction: ANSYS CFX

commercial Computational Fluid Dynamics (CFD) program

used to simulate fluid flow in a variety of applications.

ANSYS CFX product allows engineers to test systems in virtual

environment. (gas turbine engine, aircraft aerodynamics, pumps,

fans, HVAC systems, mixing vessels, vacuum cleaners, and more.)

the CFX solver uses a vertex-centered scheme.

In a vertex centered scheme, the fluid variables are stored at the

cell vertex

This means that the vertex of the mesh-element is the center of the

solver-element

Meshing: Runner (ANSYS MESH)

Meshing, Boundary Conditions

& Solver DetailsMesh Size 8 mm

Advanced Size function Off

Relevence Center Fine

Method Hex Dominant

Inlet Mass Flow rate

Outlet 1 atm Pressure

Stay Vanes & Guide Vanes Frame Change = None

Guide Vanes & Runner Frame Change = Frozen rotor

Runner & Draft Tube Frame Change = Frozen rotor

Minimum iterations 1

Maximum iterations 2000

Tolerance e-4

Parallel Processors 4

Meshing

Boundary Conditions

Interfaces (Pitch Ratio = 1)

Convergence

Solution

Grid Independent Test(Total nodes Selected 1082147)

279.9469279.9064279.8466

278.8048278.6968

278.6

278.8

279

279.2

279.4

279.6

279.8

280

0 500000 1000000 1500000 2000000 2500000 3000000 3500000 4000000

Hea

d

Grid Number

Results

Discharge factor VS Speed

factor

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

0 5 10 15 20

Qed

Ned

Results: Efficiency VS Speed factor

0

10

20

30

40

50

60

70

80

90

100

0 5 10 15 20

Eff

icie

ncy

(in

%)

Ned

0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14 16 18 20

n

Ned

4.96°

7.44°

9.92°

11.16°

12.54°

13.64°

14.88°

17.36°

18.6°

19.1°

0

0.05

0.1

0.15

0.2

0.25

0.3

0 2 4 6 8 10 12 14 16 18 20

Qed

Ned

4.96°

7.44°

9.92°

11.16°

12.54°

13.64°

14.88°

17.36°

18.6°

19.1°

C

o

m

p

u

t

a

t

i

o

n

a

l

A

n

a

l

y

s

i

s

3-D plot of Ned, Qed and Efficiency

Introduction: Hill Chart

To predict the performance of

Turbines

Two plots:

Upper plot (𝑛𝐸𝐷 (Speed

Factor) versus η (Efficiency)

𝑛𝐸𝐷 versus 𝑄𝐸𝐷 (Discharge

factor)

𝑄𝑒𝑑 =𝑄1

𝐷2 𝑔𝐻

𝑁𝑒𝑑 =𝑁𝐷

𝑔𝐻

Guide vane variation

upper plot project the

required efficiency points to

the lower graph

Hill chart obtained

Hill Chart Plot

Conclusion Literature review based on the design, analysis and theories of

Francis turbine, Hill Chart and CFD

Modeling of the stationery and rotatory domain have been

completed.

Meshing of the domains have been completed with hexahedral

mesh

Grid convergence test defined the number of nodes and elements

of the domains

Completed the simulations of the Francis turbine at Guide vane

angle 12.54° which has given the performance curve .

10 sets of simulations were performed in order to obtain

performance curves at different guide vane angles.

The best efficiency point was found in the full guide vane angle

19.1ᵒ with 93.496%.

It has been advised to operate the turbine at 12.54ᵒ at flow rate

2.35 m3/s because it has a vast operating regime and an efficiency

of 92.7567% that is considerably high.

REFERENCES

Patel K., Desai J., Chauhan V. and Charnia S. (2011) “Development of Francis Turbine using Computational Fluid Dynamics”, The 11th Asian International Conference on Fluid Machinery and the 3rd Fluid Power Technology Exhibition, November 21- 23, 2011, IIT Madras, Chennai, India.

Jain S., Saini R. P. and Kumar A. (2010), CFD Approach for prediction Of Efficiency Of Francis Turbine, IGHEM-2010, Oct 21- 23,2010, AHEC, IIT Roorkee, India.

Čarija Z., Mrša Z. and Fućak S. (2008), Validation of Francis water turbine CFD simulations, Croatia.

Vu C. Thi., Koller M., Gauthier M., Deschênes C. (2010), Flow simulation and efficiency hill chart prediction for a Propeller turbine at various design and off-design conditions, Switzerland.

Laín S., García M., Quintero B., Orrego S. (2008), CFD Numerical simulations of Francis turbines, Columbia.

Neopane H. (2013), Lecture Slides on Hydraulic Turbines, Kathmandu University, Nepal.

Pudasaini S., Pathak A., Chaudhary B. (2013), Proposal on CFD Analysis of PeltonTurbine, Kathmandu University, Nepal.

Paulsen J., FSI-analysis of a Francis turbine, NTNU, Norway.

Adhikari S., Report on Job Training at Waterpower Laboratory, NTNU, Nepal.

Barstad L. (2012), CFD analysis of a Pelton turbine, NTNU, Norway.

High Pressure Hydraulic Machinery (2009), Water Power Laboratory, NTNU, Norway

<Online retrieved> http://en.wikipedia.org/wiki/Francis_turbine, 2 October 2014

THANK YOU!