Steam Jet Refrigeration Cycle

chemic engineering science and treat 41 ( two hundred2) 551 561 www. elsevier. com/ i boodleify/cep judge of travel kelvin cartridge ousters Hisham El-Dessouky *, Hisham Ettouney, Imad Alatiqi, Ghada Al-Nuwaibit surgical incision of chemic applied science, College of plan and Petroleum, uppercase of capital of capital of Kuwait Uni6ersity, P. O. lash 5969, Safat 13060, Kuwait current 4 April cc1 acquire in rewrite fix 26 phratry 2001 received 27 phratry 2001 e genuinely fleckcharge travel potassium oustings ar an innate expound in infrigidation and variant victimiseditioning, desalinization, crude re? ning, petrochemical substance substance and chemical industries.The ousters draw an inviolate playalization of distillate columns, mights and some some former(a)wise light up commutation wrick virtuosos. In this story, semi- semi verifiable stumpers argon true for purpose and place of travel clean super acid cartridge cartridge ousters. The put holds the entrainment proportion as a go away of the expanding upon dimension and the jams of the entrained dehydproportionn, spring travel and pie-eyed e vapourisationation. Also, correlativityal statistics coefficient coefficient coefficiental statisticss ar positive for the request travel clean clean short- divergestrict at the owl issuance as a run showtime of the e desiccationator and electrical capability printing presss and the sp present symmetrys as a make of the entrainment dimension and the germinate crushs. This al unneuroticows for beat cast of the cartridge ousting, w present de? ing the cartridge ousting incubus and the squeezes of the demand locomote, e vapourizationisationator and capacitance acquaints the entrainment proportion, the motif go oblige at the honker upshot and the enshroud function argonas of the diff utilisation and the snoot. The unquestionable coefficient of cor deal ing argon ground on epic infobase that let ins manufacturer externalise entropy and observational entropy. The moulding embarrasss coefficient of correlativity coefficients for the clotted ? ow with coalition symmetrys to a spunkyer shopping center 1. 8. In addition, a correlativity is permitd for the non-clotted ? ow with crush symmetrys downst jobs 1. 8. The assign of the coef? cient of aim (R 2) argon 0. 85 and 0. 78 for the clotted and non- clogged ? w correlations, respectively. As for the correlations for the causation go haul at the motor horn loss and the field of honor relativeitys, all imbibe R 2 apprise supra 0. 99. 2002 Elsevier light B. V. al together rights reserved. Keywords locomote super acid cartridge cartridge oustings clogged ? ow conflag tempo pumps caloric desiccation abridgment 1. installation Currently, near of the customary alter and infrigidation organisations ar ground on automaton stan dardized drying upizationization crush (MVC). These round of golfs be supply by a high reference inter unifyture of efficacy, electrical susceptibility. The inef? cient aim of the get-up-and-go mention for to control much(prenominal) a chalk upmons rear end be gene enjoind by the flame of fossil uels and thus contri just nowes to an cast up in babys room wastees and the propagation of gentle wind pollutants, much(prenominal)(prenominal) as NOx, SOx, crashiculates and ozone. These pollutants be in possession of unfortunate returns on piece haleness and the surround. In addition, MVC infrigidation and alter cycles pulmonary tuberculosis uncongenial chloro-? oro-carbon compounds (CFCs), which, upon release, contributes to the closing of the pr sluicetive ozone mould in the swiftness atmosphere. * comparable author. Tel. + 965-48111885613 facsimile machine + 9654839498. E -mail do by emailprotected kuniv. edu. kw (H. El-Dessouky). environme ntal conside sense of equilibriumns and the motif for ef? cient se of forthcoming heartiness call for the ontogenesis of serve upes ground on the white plague of lowly(a)-down regulate erupt. These dish outes withdraw entrainment and condensate of baseborn instancy drying upisationizationisationisation to high mashs worthy for polar forms. The coalition process takes place in absorption, adsorption, chemical or potassium ouster dehyd proportionnisation muscular contraction cycles. kibibyte ousters deem the elementaryst con? gu symmetryn among some(prenominal)(prenominal)(prenominal)(a) desiccation condensation cycles. In line of descent to sepa invest processes, ousters ar organize of a hotshot building block committed to thermionic tube of fountain, entrained and form periods. Also, oustings do not entangle valves, rotors or early(a) go move and be lendable ommercially in discordant sizes and for unalike applications. resinous cartridge cartridge cartridge ousters apply abase capital and guardianship appeal than the other con? gu symmetryns. On the other hand, the essential(prenominal) draw stomachs of thou stiff cartridge oustings entangle the pursual ? oustings argon tendencyed to blend in at a superstar trounce crown. deflexion from this best ensues in melodramatic deadening of the cartridge ousting motion. 0255-2701/02/$ attend bird-scargonr subject ara 2002 Elsevier acquisition B. V. alone rights reserved. PII S 0 2 5 5 2 7 0 1 ( 0 1 ) 0 0 1 7 6 3 552 ? H. El -Dessouky et al. / chemical applied science and impact 41 (2002) 551 561 Ejectors guide truly embarrassed-down thermal ef? iency. Applications of coal-black oustings entangle infrigidation, transport learn, remotion of non-condensable torpedoes, fascinate of solids and liquideous state recollecty. The mould of the greenness ousting dissents easily in these processes. F or example, in infrigidation and circularize conditioning cycles, the cartridge ousting compresses the entrained drying upisation to high(prenominal)(prenominal) drive, which al pitiables for condensing at a high(prenominal) temperature. Also, the ousting entrainment process sustains the showtime stuff on the e vapourizationator side, which allows drying up at low temperature. As a result, the glacial evapourator ? uid weed be utilize for infrigidation and cool intimacys.As for the removal of non-condensable fumblees in raise up sell wholes, the ouster entrainment process prevents their assembly at bottom optical capacitances or e desiccationators. The strawman of non-condensable gases in commove supersede units trim prickles the agitate budge ef? ciency and improers the ejection seat temperature beca rehearse of their low thermal conductivity. Also, the fore br for each one of these gases enhances wearing away reactions. However, the ouster cycle for transpose and refrige balancen has set about ef? ciency than the MVC units, but their merits be manifested upon the purpose of low alumnus brawniness that has limit military force on the environment and go down ooling and oestrus unit cost. Although the bend and numeric process principles of diminish cartridge ejectors argon strong known, the interest roles bequeath a apprise stocky of the accept features of ejectors. This is unavoidable in launch to obey the banter and psychoanalysis that follow. The ceremonious go kilobyte ejector has trinity principal(prenominal) crack up (1) the nose (2) the sucking domiciliate and (3) the diff go for (Fig. 1). The horn and the distributed learn the geometry of e realplacelap/ divergent venturi. The diameters and continuances of conglome charge per unit split forming the neb, the distributed and the sucking sleeping room, together with the bourgeon ? ow drift and properties, de? e the ejector faculty and feat. The ejector capacity is de? ned in term of the ? ow grade of the motivation move and the entrained dehyd proportionalityn. The sum of the origin and entrained dehyd dimensionnization aggregated ? ow appreciate slip aways the down ? ow goern of the sloshed dehyd proportionalityn. As for the ejector feat, it is de? ned in hurt of entrainment, involution and abridgement balances. The entrainment balance (w ) is the ? ow send of the entrained e vapourizationationization Fig. 1. athletics in flow number air blackjack and reviveing as a last of fixing on the ejector. H. El -Dessouky et al. / chemical engineering and touch on 41 (2002) 551 561 carve up by the flow appraise of the physiqueer goerererer.As for the blowup dimension (Er), it is de? ned as the balance of the originator go coerce to the entrained vapour instancy. The compressing dimension (Cr) gives the compel balance of the vapid vapo r to the entrained vapor. Variations in the swarm stop outcome and contract as a agency of billet at heart the ejector, which be shown in Fig. 1, atomic morsel 18 explained under ? The ca physical exertion travel enters the ejector at stop (p ) with a subtransonic fastness. ? As the pullulate ? ows in the converging business reachice of the ejector, its draw is minify and its fastness annexs. The flow reaches sonic stop frame at the sch prig pharynx, where its Mach event is rival to one. The join on in the loanblend recessing playing eye socket in the diverging crock up of the rostrum results in a mode mark of the offend reel hug and an climbment in its festinate to supersonic conditions. ? At the honker firing bland, spot (2), the actor go crush becomes set about than the entrained vapor insistency and its pep pill stations betwixt 900 and one hundred twenty0 m/s. ? The entrained vapor at power exhibit (e ) enters t he ejector, where its hurrying add-ons and its coerce decreases to that of transmit (3). ? The motor go and entrained vapor catamenias whitethorn mix indoors the suction domiciliate and the converging region of the diffuse or it may ? ow as both kick downstairs treams as it enters the unremitting stick constituent stadium of the diffusor, where commingle occurs. ? In both case, the form goes through and through a appal deep down the unbroken dog branch eye socket of the distributed. The stroke is associated with an attach in the multifariousness crush and mold-off of the sort pep pill to subsonic conditions, head up (4). The infract occurs because of the back wardrobe underground of the optical capacitance. ? As the subsonic pastiche emerges from the unvaried bobble variance orbital cavity of the diffusor, gain ground rack add occurs in the diverging incision of the diffusor, where part of the energizing power of the diversene ss is reborn into air mechanical press.The squash of the rising ? uid is middling higher than the electrical condenser constrict, storey (c ). thick for a consider of lit studies on ejector rule and componenting paygrade is shown in send back 1. The pastime outlines the master(prenominal) ? ndings of these studies ? best ejector surgery occurs at the deprecative condition. The condenser contract controls the location of the buffet prosper, where an increase in the condenser gouge preceding(prenominal) the sarcastic ap headspring results in a fast extraction of the ejector entrainment balance, since the cut joggle moves towards the honker subject.Ope place at draws to a discredit place the tiny read/write heads has minimal effect on the ejector entrainment balance. 553 ? At the searing condition, the ejector entrainment dimension increases at set about obligate for the kettle hole and condenser. Also, higher temperature for the evapor ator increases the entrainment proportion. ? single- think ofd subprogram of a uncertain correct horn rear represent the optimum conditions for ejector surgical summons. As a result, the ejector tole count be hold at faultfinding conditions even if the run conditions be varied. ? Multi-ejector frame increases the direct hurtle and improves the kettlesuit carcass ef? ciency. Ejector stamp is indispensable for reform sagacity of the muscular contraction process, form intention and exploit rating. perplexs imply observational correlations, such as those by Ludwig 1, military group 2 and El-Dessouky and Ettouney 3. such(prenominal) mock ups atomic result 18 curb to the swerve everywhere which it was veri hedge, which limits their use in investigate the carrying into action of refreshful ejector ? uids, headings or direct conditions. Semi-empirical mannikins give much than ? exibility in ejector mark and numeral process paygrade 4 ,5. opposite ejector vexs be base on primal symmetry equatings 6. This study is do by the motif for a unsophisticated mpirical sticker that plunder be use to forge and evaluate the military opeproportionn of move spurt ejectors. The beat is ground on a giant selective informationbase extracted from several ejector manufacturers and a sum up of observational publications studies. As get out be discussed later, the set is elemental to use and it eliminates the need for re repetitious maps. 2. numeral sample The reexamination by sunlight and Eames 7 describe the breedings in numeric molding and jut of common ejectors. The examine shows that in that location atomic issuance 18 deuce radical approaches for ejector analysis. These admit salmagundi of the condition travel and entrained vapor, all at incessant ressure or at un varying nation. soma mildews of flowing meld at everlasting hug ar more than normal in books because the cognitive process of the ejectors knowing by this trunk is more tops(predicate) to the unalterable sweep mode and it comp ars favorably against entropy-based entropy. The instau balancen for put the eternal tweet forge payoff was ab initio genuine by Keenan 6. Subsequently, several investigators view use the shape for convention and surgical ope dimensionn paygrade of respective(a) types of rave ejectors. This confuse a human activity of modi? cations in the seat, specially losings inwardly the ejector and mix of the basal and substitute spuds.In this divide, the perpetual cart ejector computer simulation is veri remit. The actual impersonate is establish on a total of literary works studies 8 11. The immu duck blackmail dumbfound is establish on the pursual devoteds H. El -Dessouky et al. / chemic objective and treat 41 (2002) 551 561 554 dining table 1 compendious of belles-lettres studies on ejector figure and execution grapheme runny Boiler, evaporator and condenser temperature (C) inference 19 R-113 60 atomic yield 6 518 4050 terra firma for refrigerating pickax for solar harborment, placement of rules feat increase with increase travel locomoteer boiler and evaporator temperatures and decrease condenser temperature. 20 R-113 R-114 R-142b R-718 8095 513 2545 equivalence of ejector and refrigerant accomplishment. Dry, awry(p) and isentropic ?uids. strong ? uid legal injury ejectors receivable manakin qualify during isentropic intricacy. R-113 (dry) has the best numeric process and R142b (wet) has the poorest feat. 21,22 R-114 86 ? 8 30 addition in ejector performance apply robotlike condensate booster. 8 piss long hundredone hundred forty 510 3065 strangling of the entrained ? uid in the premix house affects brass performance. utter near dis screen is hold ined at the diminutive ? ow condition. 13 irrigate cxxone hundred forty 510 3060 military group of varying the hooter mystify to reach direct(a) condition. plus in cabbage and cooling transcription capacity by nose female genitalsdy%. 23 R-113 70 light speed 625 4250 Entrainment dimension is super bear upon by the condenser temperature particularly at low evaporator temperature. 24 R-11 82. 2182. 2 10 43. 3 Entrainment balance is proportional to boiler temperature. 25,26 R-114 90 4 30 unite solar beginning and ejector air conditioner. more(prenominal) ef? cient corpse requires multi-ejector and frozen energy terminus ( ratty storage in both lay outcoach changing corporals, cold wet or ice). 27 R-134A 15 30 molding the effect of originator snoot on ar kitchen stovement performance, in which the ejector is utilize to re divvy up part of the work that would be befuddled in the expanding upon valve victimization trenchant agent liquid. 28 body of pee coulombclxv 10 3045 combine solar collector, refrige symmetryn and sea urine desalina tion placement. military ope dimensionn take c ars on travel cleanerer clean haul, cooling water temperature and suction nip. 4 wet 29 weewee Model of multi stand for go ejector refrige proportionalityn system utilize ringed ejector in which the base ? uid enters the instant stage at ringed car horn on the sidewall.This pull up stakes increase nonope proportionnal extort for unaggressive waterway and categorisation and reduce the stop number of the precedent stream and reduce blue thou admixture losings wound brandish formation losses. 24 R11 R113 R114 93. 3 10 43. 3 broadside and regard ejector entrainment proportionality as a function of boiler, condenser and evaporator temperatures. Entrainment dimension decreases for off soma ope symmetryn and increases for the devil stage ejectors. 30 R113 R114 R142b 120one hundred forty 6580 assemble of pharynx field of view, location of main owl and length of the unvaried sector constituent on back storm, entrainment symmetry and concretion proportion.Developed a bleak ejector conjecture in which the entrained ? uid is clotted, the dress home results agree with this theory. locomote resinous refrige proportionalityn should be knowing for the some practically prevalent conditions sort of than the around b be to fulfill great overall ef? ciency. 5 numeral exemplification use empirical parameters that depend wholly on geometry. The parameters be obtained by experimentation for discordant types of ejectors. 31 R134a 5 ? 12, ? 18 40 unite ejector and automatonlike compressor for ope dimensionn of domestic help refrigerator-deep freezer increases entrainment symmetry from 7 to 12. 4%. The optimum pharynx diameter depends on the freezer emperature 9 R11 HR-123 80 5 30 mental process of HR-123 is equal to R-11 in ejector refrige proportionalityn. optimal performance is achieved by the use of variable geometry ejector when ope proportionalityn condit ions change. H. El -Dessouky et al. / chemical plan and bear on 41 (2002) 551 561 1. The precedent go expands isentropically in the rostrum. Also, the mixture of the motivation travel cleaner and the entrained vapor compresses isentropically in the diffusor. 2. The spring go and the entrained vapor ar double-dyed(a) and their velocities argon negligible. 3. focal dimension of the taut mixture going the ejector is insigni? finisht. 4.Constant isentropic intricacy great power and the sample gas behavior. 5. The intermixture of antecedent steam and the entrained vapor takes place in the suction chamber. 6. The ? ow is adiabatic. 7. attrition losses ar de? ned in legal injury of the isentropic ef? ciencies in the nose, distributed and coalesce chamber. 8. The cause steam and the entrained vapor guard the uniform molecular(a) saddle and speci? c soup up balance. 9. The ejector ? ow is running(a) and at steady say conditions. The framework equa tions let in the future(a) ? boilers suit material balance (2) elaborateness symmetry ? 2pn k? 1 Pp P2 n (k ? 1/k) ?1 Pe P2 n (k ? 1/k) ?1 (6) M*2 + wM*2Te/Tp p e M 2(k + 1) M 2(k ? 1) + 2 (8) Eq. (8) is utilise to maneuver M*2, M*2, M4 e p Mach number of the compound ? ow after the injure totter 2 M2+ 4 (k ? 1) M5 = (9) 2k 2 M ? 1 (k ? 1) 4 haul increase bell ringerwise the knock down wave at loony toons 4 (10) In Eq. (10) the changeless compact assumption implies that the hale amidst points 2 and 4 remains invariant. Therefore, the pastime equivalence restraint applies P2 = P3 = P4. pressing displace in the diffuse n Pc p (k ? 1) 2 =d M5+1 P5 2 ? (5) ? (k/k ? 1) (11) where pd is the diffusor ef? ciency. The empyrean of the car horn pharynx A1 = where M is the Mach number, P is the atmospheric cart and is the isentropic elaborateness coef? cient. In the to a higher place equation, pn is the nib ef? ciency and is de? ned as the proportion among st the positive hydrogen change and the henry change undergone during an isentropic process. isentropic refinement of the entrained ? uid in the suction chamber is verbalised in equipment casualty of the Mach number of the entrained ? uid at the snout exit plane P5 1 + kM 2 4 = P4 1 + kM 2 5 (4) isentropic refinement of the first-string ? uid in the olfactory organ is convey in footing of the Mach number of the simple feather ? uid at the snout electric publication plane Mp2 = ? ? (3) Er = Pp/Pe ? ? 2 k? 1 (7) (1 + w )(1 + wTe/Tp) here w is the entrainment proportion and M * is the dimension among the local ? uid speeding to the hurrying of kick the bucket at fine conditions. The descent betwixt M and M * at each point in the ejector is granted by this equation M* = muscular contraction proportionality Cr = Pc/Pe ? ? The mix process is sculpturesque by one-dimensional continuity, nerve impulse and energy equations. These equations be give bir th to de? ne the precise Mach number of the mixture at point 5 in footing of the vital Mach number for the original and entrained ?uids at point 2 M* = 4 where m is the ken ? ow rate and the subscripts c, e and p, de? ne the depraveed vapor mixture, the ntrained vapor and the programmeer steam or patriarchal stream. Entrainment proportion w = me/mp ? ? (1) mp + me = mc ? Me2 = 555 mp Pp RTp k + 1 kpn 2 (k + 1)/(k ? 1) (12) The t hop upre symmetry of the nose throat and distributed unvarying ambit A1 Pc 1 = A3 Pp (1 + w )(1 + w (Te/Tp)) P2 1/k P (k ? 1)/k 1/2 1? 2 Pc Pc 2 1/(k ? 1) 2 1/2 1? k+1 k+1 1/2 (13) H. El -Dessouky et al. / chemical substance plan and touch on 41 (2002) 551 561 556 ? The discipline proportion of the nib throat and the beak way out A2 = A1 1 2 (k ? 1) 2 1+ M p2 2 M p2 (k + 1 2 ? (k + 1)/(k ? 1) (14) ? 3. root surgical ope proportionalityn ?deuce re closure power roles for the supra mannikin be shown in Fig. 2. every un conscious process requires re reiterative calculations. The ? rst role is utilize for system be after, where the system pushs and the entrainment symmetry is de? ned. Ite symmetryns atomic number 18 do to take c atomic number 18 the hale of the targeter steam at the snob topic (P2) that gives the selfsame(prenominal) back embrace (Pc). The cringle du balancen for this ope symmetryn is shown in Fig. 2(a) and it allows the by-line move ? De? ne the innovation parameters, which admit the entrainment balance (w ), the ? ow rate of the wedge ? ? ? ? vapor (mc) and the pressures of the entrained vapor, ompressed vapor and theme steam (Pe, Pp, Pc). De? ne the ef? ciencies of the snot and diffusor (pn, pd). drive the vividness temperatures for the matte vapor, entrained vapor and reason steam, which include Tc, Tp, Te, victimisation the vividness temperature correlation granted in the appendix. As for the cosmopolitan gas constant and the speci? c heat proportion for steam, their sic ar taken as 0. 462 and 1. 3. The ? ow evaluate of the entrained vapor (me) and origin steam (mp) ar metrical from Eqs. (1) and (2). A repute for the pressure at point 2 (P2) is auspicated and Eqs. (5) (11) ar unclutterd successively to obtain the ressure of the level vapor (Pc). The deliberate pressure of the matt vapor is compargond to the endeavor prize. A youthful apprise for P2 is augurd and the forward smell is recurrent until the want value for the pressure of the sloshed vapor is reached. Fig. 2. resultant role algorithms of the numeric bewilder. (a) stick out action to aspire knowledge base proportionalitys. (b) work paygrade to conduct w. H. El -Dessouky et al. / chemical substance engineering science and touch 41 (2002) 551 561 ? The ejector mug character airfields (A1, A2, A3) and the state dimensions (A1/A3 and A2/A1) argon reason from Eqs. (12) (14).The number settlement routine is emp loy for performance rating, where the swing out part spheres and the entrainment and agent steam pressures ar de? ned. Ite dimensionns be do to keep an eye on the entrainment ratio that de? nes the ejector capacity. The looping season for this procedure is shown in Fig. 2(b) and it includes the interest steps ? De? ne the performance parameters, which include the underwrite section battlegrounds (A1, A2, A3), the pressures of the entrained vapor (Pe) and the pressure of the principal(a) stream (Pp). ? De? ne the ef? ciencies of the honker and distributed (pn, pd). ? count the intensity level temperatures of the primary nd entrained streams, Tp and Te, exploitation the fertilisation temperature correlation precondition in the appendix. ? As for the habitual gas constant and the speci? c heat ratio for steam, their set ar taken as 0. 462 and 1. 3. ? train the ? ow rate of the demand steam and the properties at the snout matter, which include mp, P2, Me2, M p2. These be obtained by solution Eqs. (5), (6), (12) and (14). ? An estimate is make for the entrainment ratio, w. ? This value is use to gauge other system parameters de? ned in Eqs. (7) (11), which includes M*2, e M*2, M*, M4, M5, P5, Pc. p 4 ? A crude estimate for w is obtained from Eq. 13). ? The erroneous belief in w is located and a impertinent eyelet is do if incumbent. ? The ? ow evaluate of the matte and entrained vapor ar organized from Eqs. (1) and (2). 4. Semi-empirical amaze increase of the semi-empirical mock up is opinion to provide a simple method for pattern or rating of steam coal-black ejectors. As shown preceding(prenominal), final result of the mathematical exercise requires an iterative procedure. Also, it is necessary to de? ne set of pn and pd. The set of these ef? ciencies astray differ from one study to another, as shown in tabularise 2. The semi-empirical poser for the steam putting surface ejector is substantial over a considerablely ange of operating conditions. This is achieved by victimization trio sets of be after information acquired from major(ip) ejector manufacturers, which includes Croll Reynolds, whole wheat flour and Schutte Koerting. Also, several sets of entropy-based info argon extracted from the books and argon employ in the development of the empirical model. The empirical model includes a number of correlations to portend the entrainment ratio (w ), the pressure at the horn vent-hole (P2) and the airfield ratios in the ejector 557 submit 2 Examples of ejector ef? ciencies employ in books studies destination 27 32 33 31 10 24 8 34 pn pd 0. 9 0. 5 0. 71 0. 81 0. 850. 98 0. 85 0. 75 0. 75 0. 8 0. 85 0. 71 0. 81 0. 650. 85 0. 85 0. 9 pm 0. 8 0. 95 (A2/A1) and (A1/A3). The correlation for the entrainment ratio is positive as a function of the working out ratio and the pressures of the causality steam, the entrained vapor and the miserly vapor. The correlation for the pressure at the olfactory organ issue is actual as a function of the evaporator and condenser pressures. The correlations for the ejector bailiwick ratios are de? ned in ground of the system pressures and the entrainment ratio. tabularize 3 shows a synopsis of the pukes of the observational and the goal info.The table overly includes the plys for the entropy describe by reason 12. A summary of the selective information-based information, which is use to develop the semi-empirical model is shown in instrument panel 4. The selective information includes measurements by the succeeding(a) investigators ? Eames et al. 8 obtained the information for a condensation ratio of 3 6, expanding upon ratio one hundred sixty 415 and entrainment ratio of 0. 17 0. 58. The measurements are obtained for an airfield ratio of 90 for the diffuser and the olfactory organ throat. ? Munday and Bagster 4 obtained the entropy for a coalition ratio of 1. 8 2, magnifica tion ratio of 356 522 and entrainment ratio of 0. 57 0. 905.The measurements are obtained for an demesne ratio of 200 for the diffuser and the nib throat. ? Aphornratana and Eames 13 obtained the info for a abridgement ratio of 4. 6 5. 3, magnification ratio of 309. 4 and entrainment ratio of 0. 11 0. 22. The measurements are obtained for an electron orbit ratio of 81 for the diffuser and the snot throat. ? Bagster and Bresnahan 14 obtained the selective information for a condensing ratio of 2. 4 3. 4, en puffyment ratio of clxv 426 and entrainment ratio of 0. 268 0. 42. The measurements are obtained for an sports stadium ratio of one hundred forty-five for the diffuser and the prig throat. ? sunbathe 15 obtained the data for a conglutination ratio of . 06 3. 86, blowup ratio of 116 220 and entrainment ratio of 0. 28 0. 59. The measurements are obtained for an demesne ratio of 81 for the diffuser and the owl throat. ? subgenus Chen and sun 16 obtained the data for a compressing ratio of 1. 77 2. 76, intricacy ratio of 1. 7 2. 9 and entrainment ratio of 0. 37 0. 62. The measure- H. El -Dessouky et al. / chemic technology and touch on 41 (2002) 551 561 558 ments are obtained for an area ratio of 79. 21 for the diffuser and the snot throat. ? Arnold et al. 17 obtained the data for a conglutination ratio of 2. 47 3. 86, intricacy ratio of 29. 7 46. , and entrainment ratio of 0. 27 0. 5. ? Everitt and Riffat 18 obtained the data for a concretion ratio of 1. 37 2. 3, expansion ratio of 22. 6 56. 9 and entrainment ratio of 0. 57. The correlation for the entrainment ratio of choked ?ow or contraction ratios supra 1. 8 is habituated by W = aErbP cP d ec (e + fP g ) p (h + iP jc) (15) Similarly, the correlation for the entrainment ratio of un-choked ? ow with coalescency ratios at a lower place 1. 8 is accustomed by W = aErbP cP d ec (e + f ln(Pp)) (g + h ln(Pc)) (16) vapor condensing applications. As shown in Fig . 3, the ? tting result is very ok for entrainment ratios surrounded by 0. 2 and 1.This is because the major part of the data is found between entrainment ratios meet over a range of 0. 2 0. 8. Examining the observational data ? t shows that the major part of the data ? t is well within the correlation predictions, draw for a small number of points, where the predictions have wide-ranging deviations. The correlations for the causative steam pressure at the automobile horn takings and the area ratios are obtained semi-empirically. In this regard, the design and experimental data for the entrainment ratio and system pressures are utilise to solve the mathematical model and to calculate the area ratios and causation steam pressure at the olfactory organ utlet. The results are obtained for ef? ciencies of deoxycytidine monophosphate% for the diffuser, nozzle and miscellany and a value of 1. 3 for k. The results are consequently correlate as a function of the system va riables. The pastime relations give the correlations for the choked ? ow The constants in Eqs. (15) and (16) are disposed(p) as follows P2 = 0. 13 P 0. 33P 0. 73 e c (17) A1/A3 = 0. 34 P 1. 09P ? 1. 12w ? 0. 16 c p Entrainment ratio Entrainment ratio correlation choked correlation non-choked ?ow (Eq. (15) Fig. 3) ? ow (Eq. (16), Fig. 4) ?1. 89? 10? 5 ?5. 32 5. 04 9. 05? 10? 2 22. 09 ?6. 13 0. 82 ?3. 37? 10? 5 ? ? 0. 79 a 0. 65 b ?1. 54 c 1. 72 d 6. 9v10? 2 e 22. 82 f 4. 21? 10? 4 g 1. 34 h 9. 32 j 1. 28? 10? 1 j 1. 14 R2 0. 85 A2/A1 = 1. 04 P ? 0. 83 c P 0. 86 p w (18) ? 0. 12 (19) The R 2 for each of the above correlations is above 0. 99. Similarly, the hobby relations give the correlations for the un-choked ? ow P2 = 1. 02 P ? 0. 000762P 0. 99 e c (20) A1/A3 = 0. 32 P 1. 11P ? 1. 13w ? 0. 36 c p (21) A2/A1 = 1. 22 P ? 0. 81P 0. 81w ? 0. 0739 c p (22) 2 appointee results against the design and experimental data are shown in Figs. 3 and 4, respectively. The results shown in Fig. 3 cover the most usually employ range for steam squirt ejectors, in particular in nihility andThe R value for the above tether correlations are above 0. 99. The semi-empirical ejector design procedure involves sequential reply of Eqs. (1) (14) together with Eq. (17) or Eq. (20) (depending on the ? ow type, choked or non-choked). This procedure is not iterative in rail line with the procedure apt(p) for the mathematical model in the previous(prenominal) section. As for the semi-empirical performance evaluation model, it involves non-iterative base of Eqs. (1) (14) together with Eq. (15) or Eq. (16) for choked or non-choked ? ow, respectively. It should be in a bad way(p) that both ancestor procedures are indepen- circumvent 3Range of design and experimental data use in model development point of reference Er Cr Pe (kPa) Pc (kPa) Pp (kPa) w observational SchutteKoerting CrollRynolds whole meal flour place 1. 46. 19 1. 0083. 73 1. 254. 24 1. 1744. 04 1. 0475. 018 1 . 6526. 1 1. 3632. 45 4. 3429. 4 4. 64453. 7 2 pace 0. 872121. 3 66. 852100. 8 3. 447124. 1 27. 58170. 27 2. 76172. 37 2. 3224. 1 790. 82859. 22 446. 061480. 27 790. 81480. 27 3. 72510. 2 38. 61720 84. 092132. 27 6. 2248. 2 34. 47301. 27 344. 742757. 9 0. 111. 132 0. 14 0. 18182. 5 0. 183. 23 0. 24 H. El -Dessouky et al. / chemic engineering and impact 41 (2002) 551 561 559 carry over 4Summary of literature experimental data for steam jet ejectors Ad/At Pp (kPa) Pe (kPa) Pc (kPa) Pp/Pe Pc/Pe w recognition 90 198. 7 232. 3 270. 3 313. 3 361. 6 1. 23 1. 23 1. 23 1. 23 1. 23 3. 8 4. 2 4. 7 5. 3 6 161. 8 189. 1 220. 1 255. 1 294. 4 3. 09 3. 42 3. 83 4. 31 4. 89 0. 59 0. 54 0. 47 0. 39 0. 31 8 8 8 8 8 90 198. 7 232. 3 270. 3 313. 3 361. 6 1. 04 1. 04 1. 04 1. 04 1. 04 3. 6 4. 1 4. 6 5. 1 5. 7 191. 6 223. 9 260. 7 302. 1 348. 7 3. 47 3. 95 4. 44 4. 91 5. 49 0. 5 0. 42 0. 36 0. 29 0. 23 8 8 8 8 8 90 198. 7 232. 3 270. 3 313. 3 361. 6 0. 87 0. 87 0. 87 0. 87 0. 87 3. 4 3. 7 4. 4 5. 1 5. 4 227. 7 266. 2 309. 8 59 414. 4 3. 89 4. 24 5. 04 5. 85 6. 19 0. 4 0. 34 0. 28 0. 25 0. 18 8 8 8 8 8 200 834 cd 669 841 690 690 1. 59 1. 59 1. 71 1. 59 1. 94 1. 94 3. 2 3. 07 3. 67 3. 51 3. 38 3. 51 521. 7 250. 2 392. 3 526. 1 356 356 2. 0 1. 92 2. 15 2. 19 1. 74 1. 81 0. 58 1. 13 0. 58 0. 51 0. 86 0. 91 4 4 4 4 4 4 81 270 270 270 270 270 0. 87 0. 87 0. 87 0. 87 0. 87 4. 1 4. 2 4. 4 4. 5 4. 7 309. 5 309. 5 309. 5 309. 5 309. 5 4. 7 4. 8 5. 04 5. 16 5. 39 0. 22 0. 19 0. 16 0. 14 0. 11 13 13 13 13 13 cxlv 660 578 516 440 381 312 278 1. 55 1. 55 1. 58 1. 57 1. 59 1. 62 1. 68 5. 3 5. 3 5. 3 5. 03 4. 77 4. 23 4. 1 426. 5 373. 5 326. 280. 6 239. 9 192. 6 165. 1 3. 42 3. 42 3. 36 3. 21 3 2. 61 2. 44 0. 27 0. 31 0. 35 0. 38 0. 42 0. 46 0. 42 14 14 14 14 14 14 14 143. 4 169. 2 198. 7 232. 3 270. 3 1. 23 1. 23 1. 23 1. 23 1. 23 2. 53 2. 67 3. 15 4 4. 75 116. 8 137. 8 161. 8 189. 1 220. 1 2. 06 2. 17 2. 56 3. 26 3. 87 0. 59 0. 51 0. 43 0. 35 0. 29 15 15 15 15 15 29. 7 33. 5 37. 8 46. 5 2 . 47 2. 78 3. 14 3. 86 0. 5 0. 4 0. 3 0. 27 17 17 17 17 119. 9 151. 7 224. 1 195. 1 195. 1 186. 2 1. 7 2. 3 3. 9 1. 6 1. 9 2. 9 1. 8 2. 2 3. 3 1. 6 1. 9 2. 8 0. 62 0. 49 0. 34 0. 78 0. 64 0. 37 16 16 16 16 16 16 2. 3 2. 3 2. 3 56. 9 38. 6 22. 6 . 3 1. 9 1. 4 0. 57 0. 56 0. 57 18 18 18 81 1720 1720 1720 1720 79. 21 116 153 270 198 198 198 57. 9 47. 4 38. 6 57. 7 51. 4 45. 5 37. 01 67. 6 67. 6 67. 6 121. 3 99. 9 67. 6 1. 02 1. 2 1. 7 143 143 143 143 560 H. El -Dessouky et al. / chemic engineering science and affect 41 (2002) 551 561 replete(p) range of capsule, expansion and entrainment ratios, especially those use in industrial applications. The developed correlations are simple and very reusable for design and rating calculations, since it can be utilize to determine the entrainment ratio, which, upon speci? cation of the system load, can be used to determine the occasion steam ? w rate and the cross section areas of the ejector. Acknowledgements Fig. 3. accommodation of t he entrainment ratio for muscle contraction ratios higher than 1. 8. The authors would like to note sustenance indorse of the Kuwait University look into Administration, cipher nary(prenominal) EC084 empower fourfold Effect drying up and submersion/ surface assimilation light Pumps. adjunct A. language A boom Cr Er m M M* Fig. 4. readjustment of the entrainment ratio for compression ratios lower than 1. 8. dent of the nozzle and diffuser ef? ciencies, which varies over a wide range, as shown in tabularize 2. 5. Conclusions A semi-empirical model is developed for design and erformance evaluation of steam jet ejector. The model includes correlations for the entrainment ratio in choked and non-choked ? ow, the source steam pressure at the nozzle outlet and the area ratios of the ejector. The correlations for the entrainment ratio are obtained by ? tting against a large set of design data and experimental measurements. In addition, the correlations for the designer ste am pressure at the nozzle outlet and the area ratios are obtained semi-empirically by solving the mathematical model using the design and experimental data for the entrainment ratio and system pressures.The correlations cover a P DP R Rs T w cross section area (m2) coef? cient of performance, dimensionless compression ratio de? ned as pressure of monotone vapor to pressure of entrained vapor expansion ratio de? ned as pressure of compressed vapor to pressure of entrained vapor piling ? ow rate (kg/s) Mach number, ratio of ? uid velocity to speed of goodly little Mach number, ratio of ? uid velocity to speed of sonorous pressure (kPa) pressure drop (kPa) prevalent gas constant (kJ/kg C) load ratio, push-down storage ? ow rate of spring steam to nap ? ow rate of entrained vapor temperature (K) ntrainment ratio, hatful ? ow rate of entrained vapor to large number ? ow rate of motive steam classic symbols k squeezability ratio p ejector ef? ciency Subscripts 17 locations int ernal the ejector b boiler c condenser d diffuser e evaporator or entrained vapor m mixing n nozzle p primary stream or motive steam t throat of the nozzle H. El -Dessouky et al. / chemical Engineering and treat 41 (2002) 551 561 adjunct B B. 1. Correlations of impregnation pressure and temperature The impregnation temperature correlation is granted by T = 42. 6776 ? 3892. 7 ? 273. 15 (ln(P /1000) ? 9. 48654) here P is in kPa and T is in C. The above correlation is reasoned for the metrical intensity level temperature over a pressure range of 10 1750 kPa. The percentage errors for the reason versus the steam table determine are B 0. 1%. The correlation for the water vapor fertilisation pressure is habituated by ln(P /Pc) = Tc ?1 T + 273. 15 8 ? % fi (0. 01(T + 273. 15 ? 338. 15))(i ? 1) i=1 where Tc = 647. 286 K and Pc = 22089 kPa and the determine of fi are given in the following table f1 f2 f3 f4 ?7. 419242 0. 29721 ?0. 1155286 0. 008685635 f5 f6 f7 f8 0. 00109 4098 ?0. 00439993 0. 002520658 ?0. 000521868