D1 AN EZPERI&ENT IN BTRATMPZD MLW by MARTMA CARl 8.M. L~ The George 1asha1gtcp Unvraty (19") BUBMITYSD IN PARTIAL FWUI=TL~' DllORBK OF MASER OF ATUTi ABAOWBSET It4STZITJ *s.INST. tc, OF ThRKLOX may 1966 iIBSR ARY LINDGREN BlnatUft Of AMth@W~;uW* r* V~~art~~~jt3 Accpt"dby....( Mamteaqwfy 166 .... C *.. . on D% rtmmtal Can mtft Grafate Ntuadents An xperifant in Stratifted Flow Martial Car Submitted to the Department of Mateorolog on May 0. 19ff in partial tuftillamet of the requirements for the degre of Master of S lence. ABSTRACT A theoar it developed 4bich predicts the des1tIe of outflow of a stratifted fluid as it flos out of a tsmk. lbe geometry of the tank is oes occur in the team. sch that several diftermet but related flows These diffteret to eah other are discaused. mws and their relateonhip An esperimet. was performed to check the theory and the results are diasLused. Thesis Supervisor: iik MUloaeChrstensm Title: Professor ot Meteorolega The author Is deeply Indebted to Professor Norma Phillips tor bhi sugi~ston of the probles and hi during the course of this study. 'Lw author e thanks to Profseor Erik Mollo-ChrItease estiag and helptul Ouggestion. maUsm work. wipt. A. gSuidanoe oxpreese his for several Inter- Mrs. Jane MtNabb typed the The author thanks them all for their ecellent TABLE OF COINTJT8 is INTRODUCTION 1 Il. PHSICAL DESCRIPTION OF TM FLOW IN THE TANK 6 II., THlI2E0TICAL DISCUSSION (F WE FLOW IN THE TANK 11 1. 11 2. 3., 4. S. IV. Instantaneous density and presre but aon Deftalf the mix4 IYol r Detfing p Relationshp betvw n h l and h 2 Density of outflow dlstrl- 12 14 16 17 EXPERIMENT 20 1. Demoription of the tank 20 2. 3. Method for filling the tank Method for measuring height of the ained re- 20 25 gion V.a EXPERIMENTAL RESULTS 31 APPENDIX A 43 APPENDIX B 44 BIBLIOGRAPHY 47 1, i1MRODUCTION The pupos@ of this operiMet 19 to develop and test a theory which predicts the density o outfalow, of a stratified1fluLd of a tank wth a given geoatry. o'At The geamtry consisted of a see- tanglar tank In which a partition was intrcduod which did not ztiMd to the bottoM of the teak. An outlet sas placed on the slde of the tank at a height above %e bottom of the partition. geometry as chosen so that a This the fluid flowed cut of the tank, several ditterent but related flows ocourrte in the tank. These difterent flows and their relationship to each other will be dis- cussed as well as the experimental repalts. In the flow of an Inciwpresdble d A iwisold fluid, difterences An density of the fluid Intfluence the flow In t wo wy. Firat, a change of density al s involves. a proportlonal cheane of the inertia of the tid. a density change always invelves a change of Seo=4 body forces per muit volume in a gravittional field. If we consIder only the ntatia efects, Y h showed that In the absence of a gravitatelnal field, the steady flow of an ~a sageus l1 id li identical to that of a bhecoeneous fluid under sltilar boundary coadtitons. Only the velocity is differebt., This type of flow (absee of gravitatioal field) cra be obtainad If the flow is entirely hoiaontal, or it the flow is so rapid that tbe gravity effects are neglisible. For very weak sttion to catio ly ditfernt. teay woticn, the The efftect of gravity Is to inhibit vertical wotion and horlontal gradients oampletely. Thus the flow It8 iconned to the lev*l at whi h the dLsturbance oma"sng the motion Is situated. In order to observe both the inertia and gravity effects, the discharge of a stratified fl£ud Into a line sink is ltvestigated. The mathematic.l solution for the -dimmesional proble of a stratified fluid in a horamtal channel flowng sato a lie ank was discusosed by YAh. The de6sity variatoa In the cha il ftar m~atro the s k is con- sidered to be linear and of the for epoo: P - ji pa density at the bot P. & density at the top SInce the dORiS ty 1w26&' constant sTngD 0 Upe 4AJFP C' treSt1-a1l6 O The ccmtinuty equaton may be written 9o the usual form and the use of the strem function IE, such that Ylh simplitfis the equation of motion by Introducing a now streem function The equation of motion sa .r. Her be written as is a fUnction that mUst be deteranIed. originates from a larg The equation. of mtion becomes + the fluid reserva l r anO flaows horiontlly into the channel, then v z If -~ f YIh solvs this equation by the vethod of sEpartion of varlables and obtains -- where L " .3 solution In Walid as loag as O's It reac ed that when the Froude nsuber to greater tha Is sieo Is tipossible to separate parts of the fluid in process. avabrs less than Thus, tor.Froud regions. divides Iato two distnct motionless, amd a lower region In which all concentrated. As the FrwAoe wmber is of tUhs region of discharge, fige variation (Debbler) d , is the discharge tJ., the flow pattern an upper region.compowed There Is of fluid that does not flow Into the sik mtal ca'Theo>00 1% and aeich remains relatively of the discharge fluid Is decreased to ' also reduced to 0. the heightThe epert- of dr with the Froude number to given in 2 wtich shows the epeoriantal critical Froude number to be approximately 28. dI 1 . .. ,(6~1I ~'I 8 4- In the tat sink aes disesd which me u±sed, th . fluid d not flow into a line by Y15 and Dabbler but rather into a polut Looking down an the tnk, the stream linos in the horia ink. tal plane vould not be parallel as in the case of the line slnk Stk P61M% LwSlle* But, even with this difference, the Froude number In the point sink arrangement Is til an Indication of whether or not the flow will separate* UsIng a varlation of densty of *2 and a flow rate of 40 oc/seo, the Froude number for the expri.Mnt is 8 x 10 3. Since th4a is very rmnu smaller than 1/T = . 18, then it is reasonable to .isct that the flow outlet. In fact, the Froude number eoh density surface as being ill be oncentrated only at the So so mall that one can Imagine d*11 off one at a time at the outlet. Il. PHiSYICAL DESCRIPTION OF THE VLOW IN TZE TANK severOl different flows *opesned Whn the outlet of the tank Bs occur. In order to describ the total flow, the flow in each region will be discssesd eparately. tqgion I I the eaoaiest region to explaln since it As was shown, the Fwroad contact with the outlet. ex~eriment is m=ch less than 1/1 that the flow in h~ in contact with the outlet l that an lnterface Is face is this Is rasounable to assume of region 11 falls, each density surface slid out moe at time. The result is This lnter- produced at the level of the outlet. the dividing line between region II 1 number In direct concentrated only at the Outlet. this region is Therefore, as the height and thus it to in and nXgion III. 2 3 Fi5 4 11 falls, From fig. 4 we can see as the height of region the density outlet decrease with ti~a. of the surfaces which are removed through the Since must be the swoe, the pressure across the bottom of the partition the drop in height in partition. region II causes a flow aross the bottom o. the off at the Thus, here again, density surfaces are slid bOttom of Vezgin I , end a region I and th taant econd iace real"on. is produced betress The dsity of 1ho Surftaic are removed at the bottom of reglen 1 decrease height f vci-h with tlmo as the u. The flow 2rom ragian I to vegion II pro ces aei a mixzed which I have called region IV. rginca builds up, As the flow otatinues1 this azed Ittil It finally readhes the outlet. A, Mhi itxed regiont builds up, It tende to force the still straUt-fed roigonl wh(ih I have called region III, to riset. TiMh, t e mixed region my be cozwidered as a piston which forces region XL to rise . Th dnsity surfaces %Iobh are slid off reion III increase as thivs rogiq as forced upward. Thus, wrnm fg. 8 it lo csparent that the flud whioh leaves the outlet I made up i1 part of the fluid In rogion where the -density surfaces which e alid oft doerease with ti~e, xf; and in part of the fluid in region III, where the density surfaces wbich 3MO cknSlidofooff~ncr e with !, ti . Pto. CpOS. ___ de.id4 (O , O bf..t surj4ges tUve. by 'wpd ao sS 8. Once Is vaply the rEned region reaches the cutlet, -lited boyamty to t the fluic from region I t heh .tlt,tsbog the_ polrt LtiLamed with the flow from region Ig. -tom R. 6 gl. 6 shows the fow In the tak reache the outlet. moce the miwd ragian has This correposge to then rgio The three diumasoal view of th comblned tlom are show MI in igt. s. III goes to 0. tank is shown In fig. 7. Tho i .1 79 i OVTL9T D%-O'st y %mh-."14c-e L - IFI DQ^%$ %Mkyiqft Al -I OUTiC LT -)c (wm Ixeci) (CQ) -H '~~flA1 ~A&M~C ~eaiNA'% %n&mk 'Ri I I Cxo SAVAII j*%O ro l~ft IEANyS 1& o F' -~ i. @A v~.") ~ aWC At. Os$o ,ns lWfPSIOfA C~A'A'I,~ tows l.L ?LJoW IN TE TANK THEORETXCAL DISCUSSION OF 11 Il. The InItial d~isity distributtia in the ta~* ir umi d to be iear a density of fluid at bottom of the tasn whee bange of density frm bottom to top of the tank ha As the level Is the tank begnSe to fall, region I and II by a distance H1- (H O :h- Rand (H t X.) are lowered respectlvely. The instantaneous densities In region 1 and U are obtalned by translating the initial density distrIbution by the amount each level falls. ex . 3Ieek6Wois AeI . * Ustan ye 4 sdamsa Sta i tj ee kt P 'it $* the same procedure, the mnmtantaneou and IR 1-4) Po*9.Q(I*.raV preasures at height 'A Are i lurtSRiC esssue sk6*48$..$ R,.xsineamos PL4. L ?($9 12.Y Sinice the pressures on both saides of the bottom of the partition are eJqual 2 0 z ed (Bore then to n e a d ,at 0 afto P rhEg 1e IVy e n4 e j3 $ 4) udpe tlo () 3. Dettatasz the Nimed layer Befor, the mixed sone IV xtends up to lI , the denity sur- fames In region III aMunst be ascnding at the rate: (.)X. Mfte,.. * A% d% due to the 4dded volume of fluid frea region I to regon 11. on this constant volum assDmO aton wa can determine a relation between the height of the mixed region Ar (I3- Based U- ) ad Ax (aRs.phn the height of-the uixed region can also be deftned in a different and more realistie manner. regiso IV ftro Siaoe the density of the fluid, entering region I, I* decreasing we may expect the top of the Ixed layer to have a density alset This a shaoa in fig 9. equal to ( Yo 1$ , qI h In region III eah Qemslty awsnofamb A~ Ax tb PmAPo t 1Xrd4 reglci Is Om CLPC* l-- i - 'is- 4~ /t~5las~)r Thus by OwUatfgt .04 ver-On . (t A4 In region I Isr aet N (4aI,) for tho height of the m q - po The ILntntamem5 4ultY at heght 4". tr 44 ~tOUGO O k4$- kl')1 dna1ty at em top of the 4imsv at tap 4mlyk vl% UP Z di UW64 Pn Ma /I-- , w iam sox dla 1a4ry Ax'(7P) 140 In the co=tant volume assumptions tb wll top of the aizad region reach the outlet whim a =- Ai (- H) On the other hand, In the constant deisity aweamption (eq. 6) the top of the atred region will reach the outlet when - Am t AiA . (r9) At + ATL It wo equate equation (8) and equation (*), we obtaint Am -t Ar (10) =R AX A Thb, ~ram equatlO variattio assumptie A-4Por (10) it to clear that ther does not exist any of the given tank ,geomtry for Thich the costant and the o0nstant deMsity masumtion olume Ill1 be the same. S. D.bIzmiaae P nws detiaed earlier as the mean IV, Until the mixing region extends up to lsity in volume III and Iz , the change of is caused by the fluid entering and leaving region III and IV. 8ince the volume of region III and IV remains the same, then the emount of fluid entering this reion maet equal the amount leaving. Drnsty of ftbgd enteIft rglmQ I I and IV Is.- Density of fluid lea itg region III amd IV Is: e %1A The efatiOfln S- %AZ- acOPftltfg the jam (.w~ where F px (3 ,0,) Is the t1ow rate into the rqicni wiL k- (12) tA3 IFLALAI Integated ThiS equation oa"a aR ( euI r In region IIaIac IV In aaft* of (" a- L A c 43X it rvxx I = A- ~i 'i ZIt(FCt4a) . [(A% 145 vibere 60) t~~o3 14,v ;CC ly i P ~f~ UtU, pr J;3 ; iLH + Am TI 14 L'Ar tA)( ~3)- AIz41~}c: (Axt Ar) t Axht Ar \A2 A. U%'t) Thus~ (2-4 - LP As 3-%-. iA) PO)z Po + -VriUiV tL~kpkl)( I- (13) fo (4+iy 4. lelatl~oR~p botwm a, =i prosoure. at The lustent aonou .W" derived as It ums also derived am 44 .t.]I p (13v- 1*) equating ftese tw. eapreolons md jut.oicn wo obtain a quaadrottle rolatloa bteat Lp it fl- 't YX 9 the emUaton for ancl 'y AP & + A B 14. 2A X (A: -W A ALbl4 A%)-(k4A3) * AIAr 1.kzj 0 outlet. Oin(e the b~eght of the Mned~ regla heirght$ then equMtio! AS (14) Is not vaV.d cmcathe a1zed reglon reachats the outlet., the on VOC0 Sm Mntined earllvr the SIUid fro!M ifted tnaoyantly -to tho hlght of the*outlet. I is determine the relationship betv "-a'k, 8 Md the QM30utt eglo Thu 1 , In order to the amgunt of mixing thich the boyrant set Umdergoes ulie ri.%ng Is neaded.9 thIle Is very difficult o the enperlcntal obtai, and k? glue* 113.1 be used In jeternl5 ag the deneity of outflow once the mixId region has reached the outlet* Before tUs aixed region has reached the OutletO the outlet atve= is of 2 paxrts: ed oompe region III* FIt and the flow frm rnegion 1L and the flow frcsm Rluxsout fw are Isve Of r~e on, 11 ad III rspoctIvey, the eQuation for the donlty of autfloir Is: Thus p~ ~ 113 PeeE - (,H F, -t 1 za f~9 dt; F.= where -xOa Ar k In order to eliminata from the equation, dividing e te . by F yields /= Azs dthdt . A WE I4L dt /dk Tho density of outtlow become We a k% and , . outlet streasm antly lifted fr fron the qadratSc relation between dJ/d, compute After the mized region has reached the outlet, the s agan composed of 2 parts; the flldd which ts buoy- ragion 1, end the flow from region II Itf t to assumed, as previoualy stated, that the buoyant j t does not aix w1th the now stationary mixed region, than the equation for the density outflow is s + c z By eliminating tim frm the equation, the density of outflow becames lov (djr ( +rfAL where andih In } I ( 17)o cm1mlated tra te. &V'riwatanly cdowlv" 42. 206 1. IDespqrition of the teak The exsperimntal glass to k. The tank was 46 am 15 am daep and 90 cm hlgh, 54. cn from the bottom of the The partition me placed 30 am from the left and left :j 0s MeBthod for tilMing th tasu Tioomethode wre used to 1ll gradient. edge of the tas a gap of 18.6 on from the bottom of the teak. : 2. tbde area wa The round outlet .18 oain tank, carried out In arectangular pztq-Y wrh was In the firt vater, each withb metho d, the tank with a Inear donsity disttact layes .of 1000 o of malt difeort desity, were super-wlposed on each othar. The densmdt solution was frst. added to the tek lighter layer was floated on the proviou oeam. and then each succeeding In order to obtain ditfferent donitte i vtereac 1ayr, a know aleount of trerh measured in a 1000 cc greaduated Cy11ndear and sal P wva ated salt ~ator, 1*2, Was then added to obtain 1000 cc of salt solution. Tho solution was than thoroughly niaed. The arount of fresh water ji added in each 1000 cc of solution is given in Table 1. oc The apparatus used for the floatation process Ib shom below in Fig. 11. to sUpport SiRtL fwpovatus aor Cf.tcluse spo it h this floating board, e the lighter fluid floated on top of the heavier fluid aith almost no dieturbance of the liquid interfact. A period of about 24 hours was used to permit the diffuston proces to smooth out the abrupt density diffterences I the adjacent layers and thereby producing a linear density gradient. A second method of fillng bet n 6 and hours to fill the tank was tried because it the tank tk b the layering nethod. by In this second method, a liquid of density slowly at a rate of flow V1 liquid of density zo . took Inateo a o was introduced ixing vessel containiag a seond At the same time, the liquid In the mixng vessel. me transferred to the tak at a volume rate Va . 22. TAMBL 1 Amount of fresh water In 1000 co of satwrated s1lt water fresh water Layer 3 4 6 7 9 10 11 12 13 14 15 18 of tresh 0 18.87 31.7 47.6 83.8 19.4 98.2 127.0 80 21 t2 3 24 26 28 27 2a 29 30 31 82 33 34 cc of Fresh Water 412.7 428,0 444,4 480.3 478.2 492.1 807.9 8238 539.7 142.0 174.6 190.8 206.3 222.2 23.1 37 38 269.8 301.6 317.8 40 41 42 43 44 48 349.2 3865.1 881.0 380.7 47 4. 49 80 17 1 Layer No. slture $71.4 887.3 603.2 419.0 634.9 680.8 066.7 682J. 698.4 714.8 730. 74040 777.8 793.7 Layer SI 62 53 54 5 87 88 89 00 61 88 83 cc o Fresh -Water 828. 4 873.0 888.9 904,68 920.6 93M8. 982.1 98.3 984.1 1000,8 The ditferet1al euatio s decoribl9gJ the above arrangeat awe: 4t where V1. is the volum of liquid I volume setcun ated In the tank, and t the mintag veswM,1 represents tae. V is The solu- tion to these eq~ations is: The nitWal condtions ares For the casewhere Lt 2 A * eqAawtion a) ecomes Which desribes a linear gadlent In the tank. The aethea used to construct such a linear denalty gradient in the tank ias to use pumps to control the flow rate in and out of the a.2mng vessel. 11q4d traisfer proes, the liquid In both vese.1s ga1ls at the sam rate, then Two pumps wre ueed one to pump the liquid Into the aIuIng vessel, and the other to pp needle Va1 the sixed liquad lnto the tansk. A was used to control the flow sumch that the levels i n both the vessels reinated the ia. A annmter on eacW vessel u8 uwrd to check that the levals in each vessel up Is Illustrated itn fig. 12 a the emS. TIs aot L-L soat C.Ai-ev 26 . 3. Method for itsuria tho height o h mied re Ion In the provias dlscussion, tw*o dfferest defaiitslos in doeaibing the height of the vixed regBi . In one ea~a, iere give a con- stant volume relationship eas assumed and in the othsr, an equal density relationehlip was asumed. To doteine which rlattleship the fluid obeyed beat, a sail speago soaked to mthyblue was plaed at the bUotto As the fluid pesed aeross the partitioua blue color, and the height of the coaUd be deterdzned. n ble 1't it of the WtItttt.o. picked up a charactewrist~ mixed region as a function of height This it aoun in fig 134 ---------- = .7' FI.13 4. athMd for seasnaesthe dmittr tradet The first sad easest method used to ueasu e the density gradiat was to obtain amples of flud at given podtioneA there elste pepoolk at the bottom and near t . of the tank. Since ddle of the tank, mall samples we. removed and their densities Ieasured with a hydrometere . A sall Msaple was also obtained fwe tank. -A straight line ws drlaa frJe the top of the these points and the density J7 as calculated. gricat This Is aboy In fig. 14. I I ---The seand method whioh m the densty gradient used to obtei we to fill ping-pong balls with a solutico deasit3r ,- , water of known of sat am to measure the height at which they floated IJ the ta3k~ This method ms mly approximate because of the weight of the balls. Also, due to the sase of the balle, it bthheight at which they floated. eo ---- Ps diffic alt to deteralne This is shon in fig* 15. -- -- -P,, - , P.P.0g In order to o"rmame the problems assolated with I A list of the small drops of tasoluable orgaloecopound s ere used. e oeepods tiSd he demsity range of 1.0 %nsoluable arg given in table f elt . UMntortunastel, balls, 1.8 is mest et these coapo0nds are d1f- to obtain and are very eopensve. The case bich were ouovnpfeu "wtsm owelmrsa ounmd *acr almITOOTo TFqse omago TPZLE 2 ALLY &CeUt04t O Amyl A 'fuy1.orY1t. Bawl Gaotate BMWl .5140i Bousyl blityrat* besyl cyanide Bgmayl eIthor Bssyl gozste 8oasy1 pnrptste Ssmql pVpwtdino (2) (a) Bawly salloytate (j) u)1077 Rutyl furoato (a) Butyl 3-turylaorylate Butyl ndtralto (ISO) Mhoro butywmitrIts Chiozo etia nsu (0) Chioraoethylbnus" Ca) bty1 2-cooo-4 tort buatyl, 4w-2,11) CMoro - bha~o Ca) Chioro styzen. Ca) Chioro styrone C)1*110 Chioro tolune Dially oxalate PlAMYl pbalat. DIawy1 tawtwate Dtabloro poutane (1,5) Dichlore pestano (M,) Wdethyl acetyl suclmate Diethyl allyl Maoat Dletbyl busyl "mlosto Diethyl, gltaoosate Edethyl aslsato DI9thyl omaoto mIlaftts. "etr Diethyl 0hhlt (0) 1*losl eater Otethyl phtbalato (a) DIetwy iont oiethyl Isoftsuaclato Difloro 1.1 dlobloroethane D"iathyl adlpat. !imethy]l assacemste DIftww wptaadne 1 (a) Dimethy ugphtbyle"nne (1,4) Dipropyl sulfite (a) 1.180 10032 10057 1.006 1.443 1.018 1.036 1.081 1.036 1.05S4 1.056 1.048 1.015 1.102 1.055 1.045 1.149 1*194 1*102 1*082 1.055 1.022 1.003 1*094 1.003 100 1.000s 1.077 1.050 1.070 1.131 1.121 14*13 1.040 1.6031 1.494 1.003 14121 1.0042 1.010 1.030 30. Ethyl 1c0tla1oyat157 Ethyl a seate (P) Ethyl beawyl acetoacetate Bthyl a-chloraoproplonate 1.103 1.e38 1.08? Ethyl cumsate (trans.) 1.049 Ethyl hydro slnn4sate Ithyl Methyl saeto-acetate Ethyl L-naphthylamine Sthyl phsaylaetate Ethyl pyrua te Sthyl saliOate (0) Ethyl tuluate (0) Ethyl tuluate (a) Ethyl tulauate (P) f wfuryl acetate Gluoos (a) pentapreplanate Glyeawyl tributyrate Glyoerly trivalerate a4e.ic attrite haUthyl saloylate Methyl P-ansyl Methyl befoglacetate Methyl diphenylamine (N) Methyl ethyl Sucotate Methyl pheaylaoetate Methyl toltate (0) Methyl toluate (a) Nitro ethylbenmene (0) itro ethylbeno e (P) Nitro propens (3.1) Nitro 0-Qlene (3;1,2) Nitro a-cylene (2;O,3) Nitre a- lene (4;1.3) Phemyl ethyl alcohol (a) Phg Yl tso-thLtcyanate Pheayl toluene (a) Propyl besocate (n) Pzopyl p-*tluUe culonate Yhiophena TUbutyl ttrate () Triethyl citrate 1.018 1.019 1.060 1.033 10.60 1.135 1.03 1.030 1.024 1.118 1.181 1.032 1.030 1.124 1.04 1.071 1.173 1.048 1.093 1.044 1.073 1.06 1.120 1.124 1.051 1.147 1.112 1.125 1.019 1.138 1.031 1.021 1.144 1.070 1.046 1.137 313, V. It ISMULTS EXPIER1IMNTAL is apparent grom the theoretical equations, in order to achieve agreement between the theory mad the experAimet , thua the orta~ia dew ty gradient aat be aeourately determined. Fig. 16 describes the density of overy fifth layer ldch w~a as a fu otie in filling the ta Fig used of the height of the free surface. of the free 1.7 describes the density of the fluid as a fuctiona s rface as the sae tank was emptied very slowly Irm the botton. aince ahe flow rate out of the tank was very sall, it ts again assumed that the fluid flowing out of the opetaig was rouved one density layer at a tie, and should therefore represent the density structure before the tank was emptted. a fig. 17, abshows that thee tw oates that very little aiag the deuity gradif imsr4na gradients are t in fig. 16 and nearly the same Shich indi- occurred between each deasity leor. aof-l3aearity of the density gradient at the betto The of the tank in fig. 18 to a result of leVtaig the teak set over night in order to smooth out the origial density layers' Fig. 18 desorlbes the density gradient obtained by usaig ts setod of controlitag the flow rate in a" to fig. 12. obtained. out of a miag vosse1 as explained Using this method, &aach smaller donsaty gradient to Also, the pointa an the graph show a greater spread than by fSlling the tank with layers of difftrent layers. The density gradent in this case was determined by uslag filled ping-pong balls. The results from two represntative eporimentes ill now be d1scuesed. 401 10 600 4A'4 50 200 10'404-. PO 1 0 (p Fil.Ck o~t%10.elr A10 J~t- t 20 13 A & 1 s oht WGAC#l cnollvno 4L01 0 Avswo(3 (I- 4a 0t oc : C-0- Fr 0 -4, to' bo c, lo-- SO -- 40 io+ 0 ro0 10 9 so Ila 10 I DO l 1c (e-O 3 Den'ly svxatervA obtavnc( lq 0 Ki 11T 0 .)SIM)c 1(00 110 frL lO4 The tbe B. brfeered -to ao e iand erimnts w rlment The in1tial conifderatos of is.eriament A are: dality gradiaent = 2.19 x de"sity variation = .18 0" c = 84.0 UH e nltial height in t ank cm The initial cor~ltions of .zpriment B are denaety radieat dnasity variation Initial height In tak = 1.4a x 10 - n .126 a 8 Com = 88.68 In the theoretieal analysis, two relations were derived for the Equation (0) w.a based on a constant height of the wmied region. volume asamption Uad equation (7) ws baed o assumption. a constant devsoty m In fig. 19, both equation (6) and equati are (7) plotted along with the .xperimemtally derived hsoght of the mlxed region. Frem fig 19 It Is obvious that the height of the ximed r~gion to govermed by the onstant volume ausmption: In experiaant'A the theoretical height reached the outlet fro the IN the theretimoo was 53.80 versus as at which thet ned aregio 1. 38 dS. The experimental height obt"Qap c urve was 583.40 cm. In eperimet B helght was 63.12 am ~iile the experisental Wtight Thu, T. equation (7) agObre from fNi. 19 and the just mentioned reosuts, very %11lwith the experimental results. d 36. /noiwIno *~v~.ov%~cAL ec~v~1 ~ e~. 7 t O A / C-- F15. 19 Hi~~o V%~4V~av 37, p In quat1on (6) gIaS III and IV. between Iantrod This quantity t- and k1 PFIs . range of msxed ret W as Introduced so that a relation a theoretial relation betwee n 20 and PiEg curve and the esperimental respetivelyl and kL 21 show the theoeteial k i v The theoretieal e . for. a given esperten tal value. In curve for oexperI . A and B to the The theorettcal reeaIts in erxpert pimetal remts. the theorettcal value of , ,w , sioe the theory i Only valid until the lose ory I audl b urve does not extend for th. total ngIreaches the outlet. mant A are vet inaw density in ro* could be derived. gy solving equation (14), is deteramied. edotas the In eaperiment B, In HoMver, the theoretical slope lowar than the of theh , A e 8eportmen B does agree with the .aperimental slope. F gs. 22 and 23 desrtbe the theoreteal and asperiaenta aitts of outlow as a respectIvely. nott o for experImental A and denB, the reion of the theorettal ourwe whth abows the density inoreasing I1 plotted from eqnation (18), of the theoret al cUrve "i b sabho from equation (1). equation (16) ae For a given thhedensity decreaesag Is plotted , b the densettes derived tfrm lower than the esperimetally derived densitieS exaperlant A ad higher or experment B. related to the fat the region 0le that the dsity larger thaM in experiment B. for This disorepe ey may be variation aper ALso. for a given t A mr , the densAites derived fm equation (17) are lowr than theoperimetal derived denties for both exe5riment A and B. This bou14d be espOeted snce 38. the equtatin does not take Into accaunt misLgagi Although the theory and experiment Is enough slailarity betw vn Is adequate. In factt, t o not exactly agree, there th~a to augg.t thhat the more linear and exzact density gradIet oul4d bo achieved, then the theory and the closely agree. xperls iporlmeat vould more I as led to this conclusion by the fact that the ntal valuasaa, such as height of mixed rsgion, vhich are not a function of the density gwradimeat were vry close to the observed values. 39. 0- ro 40 s w ev,;cnL A 40. -C 40 70 60 F%. . 40 h, Uersehl. Foe 41. 0x .. 1; eus4Jtues A- Horrub 04W\e& aD 8ot 1o to a. 50 ed4y at saj 40 eo ipyw' A 42o v - rlyt~vo*mt a 0 S110. a - f%3.?.3 0 u s,e 430 APPENDIA A Data fros3 xrapwment A R3 o 84.98 a 3 1.010 4 = .186 60.35 5.15 30.46 278.180 *2.40 25.40 23.70 223.10 20.80 19.00 17.80 160.00 14.70 13.30 12.00 10.70 9.i0 8.20 7.00 5.75 4.00 3.40 00.0 67.46 53.06 62:s 4.80 47.00 40.45 44.80 43O,10 41.95 40.90 3.900 310m 2*40 1.30 .00 1.080 1.084 1.086 1.088 1.001 1.101 1.103 1.110 1.107 1.108 .104 1.102 1.100 1.098 1.097 1.008 1.093 1.124 440 Dmai fwor~F esr~ 3 = P= nt ai 86.658 c 1.051 p W 88.00 33.15 30.15 84.70 63.25 61.60 28.30 58.80 66.65 50.15 88.8 53.85 52.20 50.78 49.35 47.00 a125 26.60 24.78 22.90 21.10 19,10 17.30 16,.25 14.7 13o25 11.78 10.30 9.00 4.60 4.760 43.8 41.30 358.6 3.55 3.20 .8 1.093 1.009 1,102 1.105 1 100 1.111 1.113 1.117 1.11 1.117 1.110 1.114 1.112 19111 1.109 1.107 1.100 1.108 1.103 1.104 45. APPatDIX B 1. Cal3ulatite of Foud* number voluatric flow nrate/ ut % F~ ~ L'g1 Sa= dpth of water to outlet *, dnsity at outlet P 3. daesity at tfree surface Calculation of height of aied region Constant vo~um relatonaaip 09.85 20 62.35 30 S8 40 45 s0 58 67.35 84.5 8.35 Constant daeltty relationabip 670.8 20 66092 64.2 60.98 87.56 65.02 30 35 4. 60 sof width 3. :from VIt Calcuation of Bxp*riMent A 06.0 03.0 000 37.0 56.0 30.5 23.0 190.8 17.8 Experimet B 4 Caoloulatic 67.0 64.0 338.5 30.0 6.0 21.0 of density of outflow 3eprimena A 06.0 038.0 00.0 5.0 80.0 60.0 47.,6 45.3 44.3 43.1 40.9 1.083 1.094 1.097 1.089 1.08S 1.078 1.076 1.073 1.006 1.066 iperi 07.0 4.0 600 50.0 82.20 49.3 44.0 41.3 38.0 ent B 1.100 1*104 1.110 1.110 1.100 1.105 1.101 1.007 1.004 1.000 47. BIBLIOGRAPUY Crays, A., 1949: Recberches theoriques sur l'e'"oulment do coauhes s es superposees de fluides de demt otaIlle Blanche. ditfferentes. La Jan-Feb, 44-5. Debleor, W. R., 1959: Stratiftd flow into a line sink. Journal of the Engineera I Mechanics Divisioa. Proceediags of the American Soiety of CiVi Englasers. July, 61-65. Gariel, P., 1949: Recherchee Ezperimmtal s sur 1'e'culemet do coauohes superposees do tluidee d ddonsetes dfferentes. La Noulle Blanckhe Jan-Feb., 58643. Lag, R. R., 1953; Some aspects of the flow of atratitted fluid. UniverJohns 3Opka;i D partmat of Civil Eloggineeria sity. Oster, G., Terbtcal Report 2. Density Gradients. solentific American. Aug., 70-78. Oster, G., and u. Yamaoto, 1963: Dnasity Gradient Techniques. Chemical Reviews, Vol. 88, No. 3, 27-288. Yh.e Ce-S., .19: Effect of density variations on fluid flow. Journal of Geophysical Research, Vol. 64, No. 12, 2219-2223. Yih, C,8S., 1958: On the flow otf tratified Fluid. Proo. Third Nat'l. Congr. Appl. Mechsaios. $57-861.