Курбатов Ю.Л., Шелудченко В.И., Кравцов В.В. Механика жидкости и газа: Учебное пособие

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TCnJIOCHa6)J{cHH5I,

~blMOBble

TpaKTbl

~n}l

3BaKyaQHH

npo~yKTOB

cropaHH}l,

H

T.~.

B

KaqCCTBC

npHMcpa

paCCMOTpHM

CHCTCMY,

CXCMa

KOTOPOH

npHBe~ella

lIa

pHC.

41. K

KaMepe

npoMblIllnclllloH

neqH

7

BCHTHJIHTOPOM 1

qepC3

B03~yIllHbIH

TpaKT

(8.

T.)

nO~aCTC}l

B03~yx

~JI}l

C)J{HraHH5I

TonnHBa.

B03~YIllHbIH

TpaKT

npC~CTaBJI}lCT

C060H

77

2 6 7

gam

'-~----..v,---~-'

...

-----v---~)

11-1

&.T.

PHCYHOK

41

-

CxeMa

CJlmlmoii

rImpaBJlH'IeCKOii

CHCTeMLI

no

C

JI

e,n

0

BaT

e

JI

h H 0

coe,nHHeHHhle

nI,npaBJIHqeCKHe

COnpOTlIBJIeHH}l (3a,nBH)f(KH

2,

peKynepaTop

3,

H3MepHTeJIhHOe

cY)f(alOllJ,ee YCTPOHCTBO 4,

peryJIHpylOllJ,HH

,npoCCeJIh

5,

HeCKOJIhKO

pe3KHx

M

nJIaBHhIX

rroBopoTOB;

rrp}lMhle

yqaCTKM

Tpy6orrpoBo,noB;

no,nbeMhI

H

onycKaHM}l;

HCTeqeHHe

B03,nyxa

qepe3

oTBepCTM}I B

rOpeJIKe

6

).

I1pO,nyKThI

ropeHH}!

y,nan}lIOTc}I

M3

pa60qeH

KaMephI

neqH

3a

CqeT

T}lrH

,nhIMOBOH

Tpy6hI

11,

npHqeM

o,nHa

TPy6a

MO)J(eT

06CJIY)f(HBaTh

o,nHoBpeMeHHo

HeCKOJIhKO

npOMTenJI03HepreTHqeCKMX

o6beKToB.

HanpHMep,

KaK

nOKmaHO

Ha

pHC.

41

K ,nhIMOBOH

TPy6e

npHcoe,nMHeHo

nap

aJI

JI

e

JI

h H 0

n}lTh

,nhIMOBhIX

TPaKToB

()l,.T.-1...,lJ,.T.-5),

npH'leM

Ka)f(,nhIH H3 3TMX TPaKTOB B CBOIO

Oqepe,nh

npe,ncTaBJI}leT

C060H

Ha60p

nOCJIe,nOBaTeJIhHO

coe,nMHeHHhIX

conpOTHBJIeHHH.

TaK,

pa6oQYlO

KaMepy

7

II

,nhIMOBYIO

TPy6y

11

coe,nHH}leT

,nhIMOBOH

TPaKT

)l,.T.-2,

B COCTaB

KOToporo

BXO,n}lT

OTCeQHble

um6epa

8,

peKynepaTop

9,

peryJIHpylOllJ,a}l

3aCJIOHKa 10,

nOBopoTbI,

onycKaHH}l,

no,nbeMbI

H

T.n.

I1oKmaHHa}l

B

npHMepe

CMCTeMa }lBJI}leTC}l C

JI

O)f( H 0

H,

T.e.

BKJIIOqaeT

60JIhIIIOe

KOJIHqeCTBO

rM,npaBJIMQeCKMX conpOTMBJIeHMH

pmHhIx

TlInOB,

pacnOJIO)f(eHHhIX

KaK

nOCJIe,nOBaTeJIhHO,

TaK

M

napanJIeJIhHo.

B

npaKTHKe

rM,npaBJIMQeCKMX paCQeTOB BCTPeQalOTC}l

TpM

nOCTaHOBKH 3a,naqH.

I1epBa}l

3a,naQa.

3a,naHa

reoMel'pH}I

BceH

CMCTeMhI M

pacxo,n

)f(M,nKOCTH

(rma)

,

Heo6xo,nHMoe

,naBJIeHHe B

KOHIIe

HarHeTaTeJIhHOH

CHCTeMhI

MJIM

B

HaQane

OTCOCHOH CMCTeMhI.

Tpe6yeTc}I

onpe,neJIIITh

78

,lJ,

a B n e H H e

Ha

BXO,lJ,e

HarHeTaTenhHOH:

CHCTeMhI,

KOTopoe

,lJ,OJDKeH

C03,lJ,aTh

HarHeTaTeJIh

(BeHTHmITOp,

KOMnpeccop,

Hacoc

H ,lJ,p.),

Hero

npOH3BO,lJ,HTeJIhHOCTh; HJIH

rpe6yeTcH

onpe,lJ,eJIHTh

p a 3 p

e)K

e H H e

Ha

BhlXO,lJ,e OTCOCHOH:

CHCTeMhI,

KOTopoe

,lJ,OJI)KHO C03,lJ,aTh

THrOBoe

(OTcaChIBalOrn;ee)

Cpe,lJ,CTBO (,lJ,hIMOCOC, ,lJ,hIMOBaH

Tpy6a,

3KcraYCTep

Hacoc

H ,lJ,p.),

Hero

npOH3BO,lJ,HTenhHOCTh

.

.ll.aBneHHe,

pa3BHBaeMoe

HarHeTaTeneM,

,lJ,On)KHO

6hITb

He

MeHhIIIe

06rn;ero

paCqeTHOrO

conpOTHBneHHH

CHCTeMbl

~Ppac4

C

yqeTOM

CTaTHqeCKOrO

,lJ,aBneHHH B

pa60qeH:

KaMepe

p H

,lJ,HHaMHqeCKHX

,lJ,aBneHHH

Ha

BXO,lJ,e H BbIXO,lJ,e

HarHeTaTeJIbHOH

CHCTeMhI

(P~~H,P~~I:.):

H

> A + +

(BbIX.

BX.)

Ham.

-

up

pac. P

Ip

.llHlI.

- P

.lllill.

(93)

PaCqeTHOe

COnpOTHBJIeHHe

CHCTeMhI

_ k

(max

0611\.)

APpac - 3all. \APL + AP

L

(94)

A

max

~

r,lJ,e

uP1:

-

MaKCHManhHoe

H3

cyMMapHhlX

COnpOTHBJIeHHH

napaJIJIenhHhIX

rpaKTOB

(C

Y M M H P 0

BaH

H e

conpOTHBJIeHHH:

Bcex

nap

a n

JI

e JI h H

hI

X

rpaKTOB

HBJIHeTCH

rpy60H:

0

III

H 6 K 0

H:

,

npHBO,lJ,Hrn;eH: K

3aBhIIIIeHHIO

MOrn;HOCTH

HarHenrrenbHoro

HnH

OTcaChIBalOrn;ero

Cpe,lJ,CTBa);

Ap~61l1

u

""

-

cyMMapHoe

conpOTHBJIeHHe

06llJ,eH

'-!aCTH

CHCTeMhI

(,lJ,0

HnH

nOCJIe

pa3BeTBJIeHHH);

klan

-

K03<pqlHlJ,HeHT

3anaca,

yqHThIBalOllJ,HH

B03MO)KHOe

<pOpCHpOBaHHe

pa60ThI

TenJI03HepreTHqeCKOH:

HJIH

npOMTenJIOTeXHHqeCKOH:

YCTaHoBKH,

a

TaK)Ke

3acopeHHe

rpaKTa

B

npolJ,ecce

3KCnJIyaTalJ,HH;

k3an= 1,3 ... 1,5.

CYMMapHoe

conpOTHBJIeHHe

~p

~ax

HJIH

~p

r

lll

npe,lJ,CTaBJIHeT

c060H:

CyMMy

Bcex

nOTeph

Ha

rpeHHe,

MeCTHhle

COnpOHIBJIeHHH

H

nOTeph

reOMerpHqeCKOrO

)1,aBJIeHHH:

APL

=

LAPTp.

+

kBBLAPMC.

+

LAp),..

(95)

r,lJ,e k

BB

-

K03<P<PHlJ,HeHT,

yqHThIBalOllJ,HH:

B3aHMHoe

BJIHHHHe

MeCTHhIX

COnpOTHBneHHH:

(CM.

pa3,lJ,eJI

E.

2.5.).

ilPOH3BO,lJ,HTeJIhHOCTh

HarHeTaTeJIH

,lJ,OJI)KHa

6hITb

He

MeHhIIIe

CYMMapHoro

paCXO)1,a )KH)1,KOCTH

no

BceM

napanJIeJIbHblM

TpaKTaM

C

Y'leTOM

3anaca:

79

Курбатов Ю.Л., Шелудченко В.И., Кравцов В.В. Механика жидкости и газа: Учебное пособие

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