7 wellclean cl 25 jun 00 a

7/24/2019 7 Wellclean Cl 25 Jun 00 A

1/22

WELLCLEAN* Module

* Mark of Schlumberger


2/22

2

Ranges For Flow

Laminar flow Turbulent flow

Fr

ictionPressure

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BinghamPlastic

Model

PowerLawModel

Newtonian

Model

Flow Rate Q


3/22

3

V=0

V= ! Va"

Laminar Flow

Velocity Profile

(Sliding motion)

Turbulent Flow

Velocity Profile(Swirling motion)

Laminar and Turbulent Flow regimes are found anywhere (pipe, concentric or eccentric annuli)

Types of Flow


4/22

8

Dimensionless number used to predit t!e "ow regime turbulent or

laminar

# For a Newtonian "uid of density "owing in a pipe of diameter D$

at an a%erage %eloity & 'Reynolds number Re(

# For non)Newtonian "uids$ formula an be adapted using t!e

apparent %isosity 'Reynolds number Re(

Turbulent "ow is a!ie%ed w!en Reeeeds a ritial Reynolds

number Re)

Calulated ritial "ow for turbulene may %ary aording to t!e

formulae used to alulate Ret!e de+nition of Re,-...$/01

RE2N3LD4 N5M6ER

VD

V#$


5/22

10

T!e E7ets of Casing 4tando7

T!e effect of t!e "asing Standoff on t!e #nnular Flow is

$ualitati%ely e$ui%alent to t!e following flow &attern

Q

Q

D

'

V'

D

V

%


6/22

11

Newtonian Laminar Flow

VL*"+T,

+

. /'V

D'

. /'V'

D''

V'

V . D

D''

if D'.'D V' . 0V

R,1*LDS

1234R Re .

V'D' .

V0 'D

. 5VD

Re' . 5 Re


7/22

12

Newtonian Turbulent Flow

Velocity P.

L

.

if D'. 'D

Reynolds 1umber

V'D' (670V'D /6'5VDRe' . . .

8 8 8

V'. 670V(For 79:)

Re'. /6'5Re(For 79:)

0&'( !0&)! +0&! V((&)

#( (&

0&'( !0&)

! +0&

! V(&)

#(&

V(

V

.#(

#

0&)('

, -


8/22

13

Newtonian Flow 8ossibilities

Lami

nar

Turbu

lent

Turb

ule

nt

+ncreasing

Flow

RateLa

mina

r

Turbulent

Lami

nar

Turbulent


9/22

14

9n"uene of 8ipe Eentriity

Laminar

Turbulent

c

"oncentric Pi&es atcritical flow rate for

turbulence Qc

ccentric Pi&es atsame rate Q"

c . "ritical #ngle


10/22

15

Corretion Table for Turbulent Flow

0 (0 0 .0 '0 0 /0 )0 0 10 (00

(0

1

)

/

'

.

(

F

L*;-R#T)R

#T+*

#P+ ST#1D*FF (:)


11/22

16

Turbulent "ow of t!e pre"us!,es0 all round t!e

pipe1

T!roug!out t!e :one of interest$ ondition on

pre"us!,es0 satis+ed for ;. mins1 W!en using C!emial Was!$ %isosity is ta


12/22

17

Turbulent 4reen


13/22

18

Turbulent >rap!is


14/22

19

E7et of 8ipe Eentriity

on 6ing!am 8lasti Fluid

Q

Q

D'

V'

D

V

% w'

D' < D

V' < V


15/22

22

ELF Flow

Four riteria are assoiated wit! t!e laminar "ow

regime to impro%e t!e mud remo%al1

# Density !ierar!y1

# Flow all around t!e pipe Minimum 8ressure >radient1

# Frition)pressure !ierar!y1

# Di7erential %eloity riterion


16/22

23

T!e density of t!e displaing "uid must be !ig!er

t!an t!e density of t!e displaed "uid

T!e Density)Di7erential Criterion

mud =

s&acer =

slurry


17/22

24

T!e Minimum 8ressure >radient

,M8>0 Criterion

%

ldis%lacing2

y'

ST3 ,#04 #(-5 ,dis%laced 4 dis%lacing- g cos

Comparison of t!e wall s!ear stress on t!e narrow

side and t!e "uid yield stress to !e< t!e

possibility of "ow1

# is a funtion of stando71# does not apply to pipes perfetly entered1

# only applies to "uids wit! 2ield 8oints

# gi%es a lower limit for "ow rate1


18/22

25

Frition 8ressure ?ierar!y

Criterion

# relati%ely flat and stable interface wit! no

&ossibility for t!e de%elo&ment of dis&lacement

instabilities6

T!e frition pressure generated by t!e displaing

"uid must be !ig!er t!an t!e pressure generated

by t!e displaed "uid1

p

ldis%lacing 2 (&

p

ldis%laced


19/22

26

T!e Di7erential &eloity Criterion

&eri+ation t!at t!e interfae between t!e

displaing and displaed "uid does not rise faster

on t!e wide side t!an on t!e narrow side of t!e

asing# is a funtion of stando71

# does not apply to pipes perfetly entered1

# gi%es an upper limit for "ow rate


20/22

27

Laminar 4reen


21/22

28

Laminar >rap!is


22/22

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4ummary

Type of Flow

4lot Flow

Turbulent Flow

E7eti%e Laminar Flow

7 wellclean cl 25 jun 00 a

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