TEST ID: 0 ACE Engineeing Acadey Hydeabad Deli Bpal une Bubaneswa Bengaluu Lucknw atna Cennai ijayawada isakapatna Tiupati Kukatpally Klkata H.O: 0, II Fl, Raan laza, Opp. Metdist Scl, Abids, Hydeabad 50000, : 00-8, 00-9, 00-0, 00-7507 ESE- 08 (elis) - Offline Test Seies MECHANICAL ENGINEERING Test- SUBJECT: FLUID MECHANICS & TURBO MACHINERY - SOLUTIONS 0. Ans: (b) 0. Ans: (b) F te tp tube cntaining alcl, ka + (0.9)(0)(.) 0.7 ka ( B ) abs ( A ) abs S, ( A ) gauge ( A ) abs ( at ) W istn il 0 c 0 () () 0.7 9 5. ka Again, F te U-tube, we can wite ( B ) abs + 0.90(y + ).60 0 ( B ) abs + 9y + 9 6 0 O, 7 0.7 + 9.6 0.7 +. 55. 55., 0.. c 7 Wit pistn alne, let pessue n te pistn Te anetic equatin gives, il sin0 0 -----------() Wit weigt added, pessue inceases t wee W A wee, A is pistn aea and anetic equatin beces 0.0sin 0 0 ----------() il Subtact equatin () f equatin () il 0.0 sin 0 0 Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: : ME _ Test _Slutins, W A il 0.sin 0, W A il 0. 0. 9.5 N 9.50. 0. Ans: (b) Te capillay ise in a glass tube is given by, s d 0.07 0.07 7. c 0 0.0 0. Ans: (a) d C.G d/ 05. Ans: (a) F an ideal gas, RT T RT Te dept f cente f pessue But A C I, c abut centid Ten, I, A. d C c adius f gyatin f plate 0.d (given) d 0.d d d 0.66d 8 d 0.085 0.95 d 0.d (appiately), T, cefficient f cpessibility f an ideal gas,. Als, O, / / Tus, At 0 at: At 000 at : 06. Ans: (d) F F Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata 0 0 0% 00000 000 H w. 5 w. 5 Rati F F H.5.5 w w 0.%
: : ESE - 08 (elis) Offline Test Seies 07. Ans: (c).5 Ttal weigt f te aangeent (00 + 800) kn 000 kn lue f sea wate displaced, 000 00 0 00 and, dept f iesin, d.5 80 Distance f cente f buyancy (B) f te base pint O, OB d.5 Let M be te etacente, ten I 0 8 BM. 00 5 Te etacentic eigt, GM BM BG BM (OG OB). (.5.5)..5 08. Ans: (a).5 M G B 0.88 0.9 a W 750kg/. b S.G.0.9 O Let te diensin f te blck be a and b and, its widt be l. Weigt f te blck Buyant fce abl7509.8 al0.90 9.8, wee is dept f iesin. 750b 900 lue f blck wic is subeged, s a l Ttal vlue f te blck a b l lue f blck wic is nt subeged a b l a l 750 ab 50 a b l ab 900 900 % f vlue f blck wic is nt subeged, is ab 50/900 50 00 6.67% ab 9 09. Ans: (b) Weigt f filled up balln + weigt f equipent + weigt f aiu allwable lad Buyant fce R 0.6 g 50 g Lad g R Lad R. 06 O, 50 0.6 50 67.86 50 7.86 kg. g F B Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: : ME _ Test _Slutins 0. Ans: (d) Buyant fce, F B F cpletely iesed bjected F B S, stateent is FALSE. F R A Fist case: L and A LL L L FR L L Secnd case: L L L and A LL FR L L L L. Ans: (b) F te given stea functin + y u and v y S, u v 6 7 / s. /s y Stateent () is cect. v u y, 0 0 z Flw is tatinal. Stateent (), is wng. Since, u 0. S, tee is n stagnatin pint Stateent () is cect. Tus, F R F R S, stateent is CORRECT. p S, stateent is FALSE. Ans: (c) We knw tat a tan g a z 0 0 0. dp g valid f bt incpessible dz and s stateent is CORRECT. Z 60 c a. Ans: (a) Te sap bubble will ave te geate pessue because tee ae tw sufaces (tw suface tensin fces) ceating te pessue witin te bubble. Te cect cice is (a). Te aiu vetical ise f te fee suface ccus at te back f te tank. Z a D D0 c tan 0. 0. 0.08 8c Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: 5 : ESE - 08 (elis) Offline Test Seies Teefe, te aiu initial wate eigt in te tank t avid spilling is a 60 8 5 c. Ans: (b) Nal acceleatin, a N g (given) R S, gr 9.8 0. 6. /s 5. Ans: (b) It is knwn f te tajecty f te jet tat t wee is te velcity f jet at te ifice F te given cdinates, i.e., and y, 0 / 5 /. /s 6. Ans: (a) In te -y plane, te ate f tatin f a fluid paticle is given by v u v0 z 0 y v0 Te te cpnents will be ze. And y gt g Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: 6 : ME _ Test _Slutins 7. Ans: (c) Te equatin f te stealines f te given flw field is given by dy d Cy y C u y y F flw t be paallel t y-ais, u 0 O, dy d y y Tis is pssible wen y 8. Ans: (b) Te tw diensinal cntinuity equatin in cylindical pla cdinates is v v 0 v O, F v v sin v sin sin Integating te abve equatin wit espect t, we get, v ( cs) + f() 9. Ans: (c) Te velcity f wate in te pipe is given by, 0 g 0 wee g 0. Ans: (a) 00.5 0.75 0 0. 5. 5.5 /s Z Tis is te Benulli equatin pe unit vlue f te fluid flwing. gz Tis is Benulli equatin pe unit ass f te fluid flwing. Z Tis is te Benulli g equatin. Ans: (a) Efficiency f tansissin we deliveedat te pipe utlet we available at te pipe inlet 0. Ans: (d) 500 0 000 8.% We knw tat 00 500 L t 50 0 0 500 t 0 500 t 0s 500 Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: 7 : ESE - 08 (elis) Offline Test Seies. Ans: (c) Te jet is deflected by 80. S, te fce eeted by te jet n te vane is F A jet + A vane L g 0 0 0 0 0 0 N. Ans: (c) F incpessible flw, cnstant. S, 0 even f unsteady flw. S, t stateent (i) is cect. Te secnd stateent is als cect. 5. Ans: (b) If tee is n le in te vane ten te fce acting n te vane is F A (+cs) Due t le effective aea f te deflected jet educes t (A a) F (A a) (+cs) A a A a [as 60] 6. Ans: (c) Cnsideing fce F (twads igt) t be fce eeted n te fluid by cntactin, te linea ent equatin ay be witten as: F n fluid A + A A ( + ) F n fluid ( A A ) A A F n fluid A A A A Tus, F n cntactin F n fluid but acting twads left. 7. Ans: (c) Re 600 S, te flw is laina and 6 6 f 0.0 Re 600 Head lss, Hence, f fl gd f gd fl 0 0.50 0.0 5 0. 5 0.707 /s 8. Ans: (a) Te enegy equatin gives : f L z gd f L d g z 0.080.5 090 0.05.5 c Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: 8 : ME _ Test _Slutins 9. Ans: (b) Blwe pwe g Q f 00. 0 800Q Q Q 0. Ans: (c) C C C 00.0800 K, K K / s C K 9.60 0.6 9.960. Ans: (d) Lsses f flw tug valves and fittings ae epessed in tes f lss cefficient K s. It is epessed in tes f equivalent lengt f a staigt pipe. Ans: (c) C K C gh H g K K. Ans: (b) 0 0 g g 0 0 0 0 Q C d 0.6 a a a a 50500 g 50 50 50500 0.6 0 00 Q 5 lit/sec. Ans: (c) u A 0 a ua 0 d d u a d 0 u 0 a z z dz ua u a 0 0 taking z Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: 9 : ESE - 08 (elis) Offline Test Seies 5. Ans: (b) In ipe flw, sea stess is ze at te cente and inceases linealy f cente t te pipe wall. 8QL d Q In a cnstant diaete pipe pessue deceases linealy. linealy. g 6. Ans: (b) wate at 0 C is 0.65 a-s Z als deceases Let D diaete f pipe and d be diaete f nzzle. Net ead (z z ) H z 0 0 z L L g L 0.5 f.. g D g D d (entance lss + pipe lss) D z z. 0.5 f. d g g f 0.07, D c, d c H 0.5 f. L D D d. g L D. g 7. Ans: (a) L L L gd L gb 0.5 7 0 0 6 [0.5 +.5 + 6] 0 H 6 6. g L L B D 8. Ans: (b) Let z and z be te elevatin f esevi and nzzle 9. Ans: (a) Te specific speed values given actually efe t te nn-diensinal specific speed (in ad/s ). Hee, again te iniu value (0.) is f eltn weel, fllwed by Fancis tubine (.0). Te ppelle tubine will ave te value f.0. Kaplan tubine will ave te igest value f.0. Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: 0 : ME _ Test _Slutins 0. Ans: (a) H d s g d g s Z d Z Assuing suctin and delivey pipes f sae diaete and neglecting elevatin canges between inlet and eit. H d s g 000 50.5 0000 s i.e., H H & Q Q let H p a b Q p i.e., H a b (Q) 0 60 Q a b Q Cpaing bt sides a 0 & b 5 H p 0 5 Q. Ans: (a) D, D 5 p H H p. Ans: (c) QH Q D H D H / F paallel cbinatin, ead eains sae but discage beces twice. p D D p H H p / / 5 5. 5 8 Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: : ESE - 08 (elis) Offline Test Seies. Ans: (d) elcity ead in delivey pipe is aiu at te iddle f delivey stke i.e., 70. Ans: (d) Te velcity vaiatin in suctin pipe f a single acting ecipcating pup is i.e., a sin avg avg a avg 0 a sin d cs0 a a 5. Ans: (d) ALN Q, L 60 Q Q Q N a N N avg 0 90 80 70 60 Q Q 00 0% Q 6. Ans: (c) Ai vessel n delivey side des nt ave any effect n suctin side. It educes velcity fluctuatins in delivey side. Hence, acceleatin ead is educed nly n delivey side. Static delivey ead is te elevatin diffeence between delivey pipe eit and pup eit. It is independent f any te paaete. 7. Ans: (b) cs cs80 0 a 0.75 Applying enegy balance t te t He g g a g g g g a / g / g 8. Ans: (b) 0. 5 a F a ( u) ( + cs ) At te stating u 0 Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: : ME _ Test _Slutins F a ( + cs ) 9. Ans: (a) T F R T F R a ( + cs) D T T i.e., 0. 50 cs60 000 7.5 kn. F F a u k cs a u kcs Te jet speed nly depends n net ead. ence F aiu efficiency u Te initial cnditin cespnds t aiu efficiency u u i.e., u u u u 00 50% u 50. Ans: (d) Wete, te Fancis tubine as adial vanes nt, te velcity f flw is always adial. If te t blade at inlet is adial ten te elative velcity (wic is tangential t te blade) is als adial. 5. Ans: (a) i.e., tan u w gh 0 w 0.8 [as g 0 /s ] 0 w 9.6 /s 5 9.6 f w 0.5.7 tan 0 0.577 0.5 0.577 0 8 Te eact value f is 5. Ans: (b) 5 9.6 tan 7. 5 Q Af f D t D f 5 9 5 0 /s. /s Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: : ESE - 08 (elis) Offline Test Seies 5. Ans: (a) tan f w In Kaplan tubine w fllws fee vte distibutin k w Tus w deceases f ub twads tip. As f is cnstant inceases f ub twads tip. 5. Ans: (c) N Ns 5 / H F N T N s 5/ L F FLT T T FLT L F / L / T / 55. Ans: (a) CD FD U F C D D U U FD CD Re.8 Re CD Re i.e. F D 56. Ans: (c) Te displaceent tickness ( * ) can be cnsideed as an iaginay gwt in te tickness f te wall s tat te utside flw can be cnsideed as unif flw. Using cntinuity equatin U R U R * U U 57. Ans: (b) * U U u U du dy du dy R R * y y y U U y du dy 9 k 8 9 8 U 9 U 8 Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: : ME _ Test _Slutins 58. Ans: (d) elcity gadient nal t te suface is vey ig as cpaed t steawise velcity gadient. u u i.e., y Cntinuity equatin ust be satisfied at eac pint in a flw u v i.e., 0 y u v y u v y 59. Ans: (d) All f te abve etds will educe te cances f sepaatin. Rug suface akes te bunday laye tubulent and te tubulent bunday laye is cpaatively less susceptible t sepaatin. 60. Ans: (c) 5 Re 5 C f 0.66 Re C f U 0.66 U Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
6. Ans: (c) Nally a specific ppety f a substance is defined pe unit ass. But f a fluid its specific weigt is defined as weigt pe unit vlue. It is an intensive ppety. S, stateent (II) is wng. 6. Ans: (d) Te cefficient f vlue epansin f a fluid diffes f its bulk dulus f cpessibility. S, stateent (I) is wng. Hweve, stateent (II) is cect. 6. Ans: (b) Reynlds nube is te ati f inetia fces t te viscus fces in te fluid flw. Tese inetia fces geneate due t te cange in entu f te fluid. At ige Reynlds nube, flw is tubulent and te velcity pfile is lgaitic. 6. Ans: (a) F itatinal flw, Benulli equatin can be applied at any tw pints in te flw. Centifugal fces will cause te incease in pessue f inside t utside edge. Applicatin f Benulli equatin will sw te decease f velcity f inside t utside edge. 65. Ans: (a) F stability f flating bdies, GM > 0. S, if a bdy wit wide ectangula css sectin is tilted sligtly, its B (cente f : 5 : ESE - 08 (elis) Offline Test Seies buyancy) sifts e twads te tilted end esulting in lage BM. S, GM will be psitive. Als it pvides a igting cuple. Teefe, te bdy will be in te stable cnditin. 66. Ans: (a) C d f ventue ete lies between 0.97 t 0.99. Tis is ainly due t st gadual vaiatin f css-sectinal aea dwn t tat and ten back t te full pipe aea. Tis esults in less fictin lsses. Hweve, in te case f ifice ete tee is an abupt cnstictin at te ifice plate. Tis causes te fatin f eddies wic leads t ige fictin lsses. Te C d f ifice ete vaies f 0.58 t 0.65. 67. Ans: (c) Te esultant ydstatic fce is given by F R A. S, F R can be deteined if and A ae knwn. S, stateent (I) is cect. Hweve, F R depends n specific weigt f te liquid in wic it is subeged. S, stateent (II) is wng. 68. Ans: (d) In steady flw, lcal acceleatin is ze but cnvective acceleatin ay nt be ze. Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: 6 : ME _ Test _Slutins 69. Ans: (c) Te unsyetic pessue distibutin n te ftball suface is due t Magnus effect. Spinning f ftball geneates lw velcity n ne side and ig velcity n te side. Lw pessue side U w U U w Hig pessue side 70. Ans: (c) At sepaatin pint sea stess is ze because velcity gadient beces ze. essue gadient is psitive wen flw is abut t sepaate. 7. Ans: (c) F blunt bject pessue dag is aj cntibut t te veall dag. Stealining avids te flw sepaatin ence pessue dag is educed. Teefe, veall dag is als educed. Stealining in fact inceases te skin fictin dag as te cntact aea is inceased. Hence, Stateent (II) is false. 7. Ans: (a) () Witut daft tube, kinetic enegy ead lss wuld ave been () Tubine. Wen daft tube is g used, kinetic enegy ead lss is. g Hence kinetic enegy ead lss is educed by g 7. Ans: (b) Kaplan tubine as ige efficiency as cpaed t ppelle tubine at pat lad cnditin because Kaplan tubine as adjustable t blades wee as ppelle tubine as fied t blades. Due t adjustable t blades, te Kaplan tubine can adjust t diffeent flw cnditin wit iniu sepaatin lss. 7. Ans: (d) Stateent (II) is te definitin f NSH. Hence, it is cect stateent. i i v NSH g g g Ha Hs Hv fs F abve equatin it is clea tat as suctin ead inceases, NSH deceases. Hence, stateent I is wng. 75. Ans: (d) Teetical ead develped by te pup is u g w He Head develped nly depends n eit velcity tiangle. Tus stateent (I) is wng. Te teetical pessue ise acss te pup is g H e u w. Hence, stateent (II) is cect. Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata
: 7 : ESE - 08 (elis) Offline Test Seies Hydeabad Deli Bpal une Bubaneswa Lucknw atna Bengaluu Cennai ijayawada izag Tiupati Kukatpally Klkata