Aliran Dalam Pipa-mekanika Fluida

LEH^LJ BLELM [H[L

[c~{hjbl`lj Aehbl (olh~lj lrl gls bh blelm scnl` sle~lj rc~rr{ (nhlsljxl bhscnr scnl` {h{l ihdl {cjlm{ljgjxl njbl~ lrl sle~lj bor ihdl ndlj sljglr {cjrhjg bh blelm dc`hb{lj sc`l~h-`l~h* Ofjrf`jxl 9 lh~ {lbl {h{l-{h{l bh ~ml` dhrl blj sxsrcm bhsr~hnsh xljg mcjgh~hmdlj lh~ bl~h sm~ dfrl dc ~ml`-~ml`* Nljxld sceljg blj {h{l-{h{l mcjxle~dlj aehbl `hb~fehd lrl aehbl elhjjxl dc nc~nlglh dfm{fjcj dcjbl~llj blj mcshj* Dlehrls bl~l bh blelm gcbjg-gcbjg bhilgl {lbl rhjgdlr xljg jxlmlj bcjglj bhsr~hnsh bl~l xljg rc~dfjbhsh mceleh slr  il~hjglj {h{l lrl sle~lj bor xljg ~mhr* Mcsdh{j sxsrcm-shsrcm hjh nc~ncbl% {~hjsh{-{~hjsh{ mcdljhdl aehbljxl lblel` slml* Rilj bl~h nln hjh lblel` jrd mcml`lmh {~fscs-{~fscs blsl~ xljg rc~ehnlr bh blelm leh~lj-leh~lj s{c~rh hr* R`c ofjqc~qlrhfj fa mlss mcmhehdh {~hjsh{ scnlglh nc~hdr*

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Leh~lj Elmhjl~ blj R~necj

Leh~lj aehbl bh blelm scnl` {h{l mjgdhj mc~{ldlj leh~lj Elmhjl~ lrl leh~lj R~necj*Fsnf~jc ^cxjfebs (<02>-<8<>% Ihdl lh~ mcjgleh~ mceleh scnl` {h{l nc~bhlmcrc~ B bcjglj dcoc{lrlj ~lrl-~lrl % shalr-shalr nc~hdr hjh bl{lr bhlmlrh bhlmlrh bcjglj bcjglj mjghjicdshdlj mjghjicdshdlj ylr {cwl~jl {cwl~jl xljg mcjglmnljg* <* Sjrd ―Eli leh~lj xljg od{ dcohe” g~lrlj ylr {cwl~jl (scnl` gl~hs g~lr ldlj rc~eh`lr nc~{l gl~hs xljg rc~eh`lr icels scelml mcjgleh~%

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R~necjr Aefw

^cxjfebs Jmnc~ (^C [c~{hjbl`lj lrl r~ljshsh bl~h elmhjl~ dc leh~lj r~necj nc~gljrjg {lbl ncjrd gcfmcr~h% dcdlsl~lj {c~mdllj% leh~lj dcoc{lrlj% s` {c~mdllj% blj rh{c aehbl* Fsnf~jc ^cxjfebs mc~msdlj ~lshf nheljglj ^cxjfebs 9 Hjc~rhle af~ocs ^c =

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Nheljglj ^cxjfebs d~hrhs (^cf~ lblel` nheljglj ^cxjfebs dcrhdl leh~lj elmhjl~ scsllr ldlj mcjilbh leh~lj r~necj* ^c f~ nc~jhelh = >?;;* Sjrd leh~lj {lbl {h{l jfj oh~oel~% nheljglj ^cxjfebs nc~gljrjg {lbl @xb~leho Bhlmcrc~ (B`* 2 Lo B` = [

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leh~lj elmhjl~ leh~lj r~ljshsh leh~lj r~necj

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nc~bhmcjsh% ec&B% nc~df~celsh od{ nlhd bcjglj nheljglj ^cxjfebs* [ljiljg mlsd {lbl mmjxl bhnc~hdlj fec` `njglj 9

ec = ;%;3 ^cB

ec = 2%2 (^c

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Sjrd leh~lj elmhjl~

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B Sjrd leh~lj-leh~lj bcjglj (^c xljg sljglr ~cjbl`% {ljijlg mlsd  bl{lr sljglr {cjbcd ( ec = ;%1 B ihdl ^c = <; * Sjrd leh~lj-leh~lj bcjglj (^c ncsl~ blc~l` mlsd rc~scnr bl{lr sc{ljiljg nc~dleh-dleh bhlmcrc~ {h{l scncem ijg ld`h~ bl~h b lc~l` mlsd  bhol{lh ( ec = <>; B jrd ^c = >;;; * 2

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LEH^LJ ELMHJL^ BLELM [H[L*

xljg mljl nl`wl hjbhdlsh nlr aeex bcacef{cb aefw hj l `f~hyfjrle {h{l% r`c qhsofs blj {~css~c nleljoc ljrl~l elhj mcm{jxlh {cmnlgh bl~h >ϋ bl~h bp blj ~cl~~ljghjg*

 B = b~ = - b & bx scild  x  x = ^  ‟  ~ 

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Blelm dfjbhsh

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RS^NSECJR QCEFOHRX [^FAHEC* Bh blelm snel{hslj qhsdfqhs {~fahe dcoc{lrlj blelm bhrehsdlj blelm ncjrd  rld nc~bhmcjsh scnlglh =

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bhmljl x = ^-~ lblel` il~ld xljg bhd~ bl~h bhjbhjg% mcj~r wldr dfm{fjcj p dcoc{lrlj% blj  = (r&[ 

lblel` ~lrl-~lrl <&>

bhscnr scnlglh

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Jf~mlehycb ql~hlnec9

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R`c efgl~hr`mho elw9

Fc~el{ elxc~9

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Bh mljl dfjsrljrl >%3 blj 3%; bhrcjrdlj mceleh cds{c~hmcj* {~fahe dcoc{lrlj `dm {ljgdlr ({fwc~-elw qcefohrx {~fahec cm{h~hs 9 = Blelm {c~slmllj hjh% jhelh j lblel` ajgsh bl~h nheljglj ^cxjfebs [~fahe dcoc{lrlj `dm {ljgdlr sc{c~ri` (j = 7

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af~ l s{cohahcb {~css~c b~f{ (f~ `clb efss* ?* Bcrc~mhjhjg r`c {h{c bhlmcrc~ w`cj r`c {h{c ecjgr` ljb aefw ~lrc l~c

ghqcj af~ l s{cohahcb {~css~c b~f{ (f~ `clb efss*

MHJF^ EF__C_*

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dc~ghll D  E = < ncsl~jxl slml bcjglj rcdljlj bhjlmhd% {Q  &>* Jhelh D% xljg ldrle sljglr rc~gljrjg {lbl gcfmcr~h bl~h dfm{fjcj rc~scnr* Jhelh rc~scnr mjgdhj igl rc~gljrjg {lbl shalr-shalr aehbl* _c`hjggl D  E =

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  a    B>g

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` E = D  E

g >

Ec|hq = B&a * DE

bh mljl B blj a nc~blsl~dlj {lbl {h{l bh mljl dfm{fjcj rf~scnr rc~{lsljg* 

Rfrle `clb efss ( gcjc~le 

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Rfrle `clb efss ( B = ofjsrlj 

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_bbcj cp{ljshfj*

Bhmljl9 Lsmlee blj Lel~gc scele r`c o~fss-scorhfj bcjglj l~cl {h{l bhmljl dcohe blj ncsl~jxl {h{l* Bcjglj olrlrlj DE = F% bhmljl hjh ndlj l~cl {c~rdl~lj ( Lsmle = L el~gc* Blj De = < % bhmljl {h{l bh rdl~dlj bcjglj ~csc~qfh~* ( Lel~gc :: L smlee

[h{hjg Jcrwf~d Ljb [m{ _cecorhfj*


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Af~ l sxsrcm fa rwf {l~leece {h{cs*

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Bhmljl r`c ~lrhf fa r`c mclj qcefohrhcs Blj r`c aefw ~lrc bh bl {h{l {l~leece% scncem dcmnleh*

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CJC^GX C\SLRHFJ ^CQH_HRCB* W`cj l {h{hjg sxsrcm hjqfeqcs l {m{ ljb&f~ r~nhjc% r`c srclbx-aefw cjc~gx c|lrhfj fj l jhr mlss nlshs olj nc cp{~csscb ls

Hr olj lesf nc cp{~csscb hj rc~ms fa `clbs ls

w`c~c `{m{ = Vw{m{%  & g hs r`c scae {m{ `clb bcehqc~cb rf r`c aehb% `r~nhjc% c = wr~nhjc % c & g hs r`c r~nhjc `clb cpr~lorcb a~fm r`c aehb%% ljb `E hs

r`c rfrle `clb efss hj {h{hjg*

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