5 - hydro power plants

8/6/2019 5 - Hydro Power Plants

1/73

Hydro power plants


2/73

Hydro power plants

Tail water

Draft tube gate

Draft tube

Turbine

Main valve

Penstock

Air inlet

Inlet gate

Surge shaft

TunnelSand trap

Trash rack

Self closing valve


3/73

The principle the water conduits of

a traditional high head power plant


4/73

Ulla- Frre

Original figur ved Statkraft Vestlandsverkene


5/73

Intake gate

Intake trashrack

Headrace tunnel

Anchor block

Surge tank

Penstock inletValve

Tunnel Inlettrashrack

Tunnel Inlet

Anchor block

Exp. joint

Shaddle

Power house

Tailrace

IV G

SC

DTR

DT end gate

Desilting basin

gate hoist

IV -inlet valveR -turbine runnerSC -spiral caseG -generator

Typ ica l Pow er House w i th Franc is Turb ine


6/73

Arrangement of a small

hydropower plant


7/73

H = 39 mQ = 513 m3/sP = 182 MW

Drunner=7,5 m

Ligga Power Plant, Norrbotten, Sweden


8/73

Borcha Power Plant, Turkey

H = 87,5 m

P = 150 MWDrunner=5,5 m


9/73


10/73


11/73


12/73

Slab concrete dam


13/73

Arc dam


14/73

Gates in Hydro Power Plants


15/73

Types of Gates

Radial Gates Wheel Gates

Slide Gates

Flap Gates

Rubber Gates


16/73

Radial Gates at lvkarleby, Sweden


17/73


18/73

Slide Gate

Jhimruk Power Plant, Nepal


19/73


20/73


21/73


22/73

Circular gate

Jhimruk Power Plant, Nepal


23/73

Trash Racks

Panauti Power Plant, Nepal


24/73


25/73


26/73


27/73


28/73


29/73


30/73

Materials

190Steel, St.42

206Steel, St.52

~ 400~5Concrete

80~5Wood

320Max. D: 1,4 m.2,4Max. p = 160 m.GUP

5160~ 1,0PE

150Steel, St.37

[MPa][m][m]

Max.

Stresses

Max.Pressure

Max.Diameter

Material


31/73


32/73


33/73


34/73

Calculation of the change of length

due to the change of the temperature

LTL =Where:

L = Change of length [m]L = Length [m] = Coefficient of thermal expansion [m/oC m]

T = Change of temperature [o

C]


35/73


36/73


37/73

ExampleCalculation of the head loss

=

DcRe

Power Plant data:H = 100 m Head

Q = 10 m3/s Flow Rate

L = 1000 m Length of pipeD = 2,0 m Diameter of the pipeThe pipe material is steel

Where:c = 3,2 m/s Water velocity

= 1,30810-6 m2/s Kinetic viscosityRe = 4,9 106 Reynolds number

g2

c

D

L

fh

2

f =


38/73

0,013

Where:Re = 4,9 106 Reynolds number = 0,045 mm RoughnessD = 2,0 m Diameter of the pipe

/D = 2,25 10-5

Relative roughnessf = 0,013 Friction factorThe pipe material is steel


39/73


40/73

Calculation of maximum pressure Static head, Hgr (Gross Head)

Water hammer, hwh Deflection between pipe supports

Friction in the axial direction

Hgr


41/73


42/73


43/73

E l


44/73

Example

m61Tg

L2chC

maxwh =

=

L = 300 [m]TC = 10 [s]cmax = 10 [m/s]

g = 9,81 [m/s2]

L

C=10m/s


45/73

Example


46/73

ExampleCalculation of the pipe thickness

m009,0Crpt

tL2CpDL

t

si

tsi

==

=

MPa57,1hHgp whgr =+=

Where:

L = 0,001 m Length of the pipeDi = 2,0 m Inner diameter of the pipet = 206 MPa Stresses in the pipe material = 1000 kg/m3 Density of the waterCs = 1,2 Coefficient of safety

Hgr = 100 m Gross Head

hwh = 61 m Pressure rise due to water hammer

ri

t

p

t t

Based on:

Material properties

Pressure from:

Water hammer

Static head

Calculation of the economical


47/73

Calculation of the economical

correct diameter of the pipe

Diameter [m]

Cost[$

]

Installationcosts,Kt

Costsforhydrauliclosses,Kf

Totalc

osts,Ktot

( )

0dD

KKd

dD

dK tftot

=

+

=

Example


48/73

ExampleCalculation of the economical correct diameter of the pipe

Hydraulic Losses

Where:PLoss = Loss of power due to the head loss [W] = Density of the water [kg/m3]

g = gravity [m/s2

]Q = Flow rate [m3/s]hf = Head loss [m]f = Friction factor [ - ]L = Length of pipe [m]

r = Radius of the pipe [m]C2 = Calculation coefficient

52

42

2

fLoss

r

C

rg2

Q

r2

LfQghQgP =

==

Power Plant data:H = 100 m HeadQ = 10 m3/s Flow Rate

plant = 85 % Plant efficiencyL = 1000 m Length of pipe


49/73


50/73

Example


51/73

Example

Calculation of the economical correct diameter of the pipeCost for the Pipe Material

21mmm rCL

rpr2Ltr2Vm =

===

Where:m = Mass of the pipe [kg]m = Density of the material [kg/m3]V = Volume of material [m3]r = Radius of pipe [m]

L = Length of pipe [m]p = Pressure in the pipe [MPa] = Maximum stress [MPa]C1 = Calculation coefficientKt = Installation costs []

M = Cost for the material [/kg]

21t rCMmMK ==

NB:

This is a simplificationbecause no othercomponent then the pipe

is calculated


52/73


53/73


54/73

Calculation of the forces acting on


55/73

Calculation of the forces acting on

the anchors


56/73


57/73


58/73


59/73

Principle drawings of valvesOpen position

Closed position

Spherical valve Gate valve

Hollow-jet valve Butterfly valve


60/73


61/73

Bypass system


62/73


63/73


64/73


65/73

Pelton turbines


66/73

Pelton turbines

Large heads (from

100 meter to 1800meter)

Relatively small flow

rate Maximum of 6

nozzles

Good efficiency overa vide range


67/73


68/73


69/73


70/73


71/73


72/73


73/73

5 - hydro power plants

Documents