Agricultural Engineering 2015 : 3 (155 ):37-46

Transcription

1 Scientific qurterly journl e-isnn Agriculturl Engineering 15 : 3 (155 ):37-46 Homepge: ttp://ir.ptir.org DOI: ttp://x.mer.org/ /ir METHODOLOGICAL APPROACHES TO JUSTIFICATION OF KINEMATIC PARAMETERS OF VOLUMETRIC SPRAYERS I.S. Кruk 1, Т.P Коt 1, О.V. Goreenko, А. Маrczuk *3, W. Romniuk 4, K. Głuszko 5 1 Belorussin Stte Agro-tecnicl Uniersity, Belrus Belorussin Stte Uniersity of Agriculture, Belrus 3 Deprtment of Agriculturl n Trnsport Mcines, Uniersity of Life Science in Lublin Poln 4 Institute of Tecnology n Life Sciences, Wrsw Brnc, Poln 5 Fculty of Militry Meicine, Meicl Uniersity of Loz, Poln Contct etils: ul. Beskizk, 7, -869 Lublin, e-mil: nrzej.mrczuk@up.lublin.pl ARTICLE INFO Article istory: Receie: Mrc 15 Receie in te reise form: April 15 Accepte: June 15 Keywors: sprying ir system yrulic system ir-roplet strem tomizers ABSTRACT Te objectie of te reserc is to justify kinemtic prmeters of olumetric spryers in orer to improe te efficiency of eliery of te process solutions of pesticies onto te objects of tretment. Teoreticl reserc ws crrie out on te bsis of te lws of eroynmics n mecnics. Te results of te teoreticl reserc forme te fountion for te justifiction of te sceme of reltie position n te min prmeters of te ir n yrulic systems of olumetric spryers. Introuction Plnt protection ginst pests, iseses n wees is one of te min elements of moern tecnologies of griculturl crops cultition. Fiel spryers ply min role in te mens of mecniztion. Te nlysis of te tritionl fiel spryers reels number of isntges. Te min of tem is irregulr plnt tretment by olume. From te portion of te process solution wic gets on plnt, 8% ccumultes on te top lyer, less tn 1% on te lower lyer, te reerse sie of te lees n stems remins prcticlly nontrete, wile tey re te min zone of pests n ptogens loction (Степук и др. 1998; Rkowski n Kuboń, 1). Compulsory eliery of rops of pesticies to trete objects by irstrem is te most effectie of ll known metos of olumetric tretment of crops (Литвинова, 1998). Tus, te justifiction of kinemtic n structurl prmeters of spryers, working on tis principle (Figure 1), is n importnt issue. 37

2 I.S. Кruk, Т.P Коt, О.V. Goreenko, А. Маrczuk, W. Romniuk, K. Głuszko а) b) с) Figure 1. Volumetric spryer (,b) n te principle of its opertion (c) Objectie n re of opertion Te objectie of te reserc ws to justify te kinemtic prmeters of olumetric spryers in orer to improe te efficiency of eliery of process solutions of pesticies onto te trete objects. Reliztion of tis purpose proies for te teoreticl reserc to justify te kinemtic prmeters n reltie position of ir istributionl n yrulic systems of te olumetric spryers. Min prt Te efficiency of te olumetric spryer opertion is etermine by consistency of te ir n yrulic systems opertion. During te tomiztion of liqui by tomizers, roplets form spry. In te spry some roplets fly t some ngle α c from te erticl line to te rigt, oters go to te left, te trjectory of te rest is pprocing te erticl line. Te ngle αc is rible, s eery roplet flies in its pt. Let us consier te bsic motions of roplets in interction wit ir strem: 1) te eition of te roplets t n ngle α c from te erticl line to te rigt, ) te eition of te roplets t n ngle α c from te erticl line to te left; 3) te motion of te roplets erticlly own. It is known tt it is teoreticlly not possible to etermine te nture of te motion of roplets like ny oter mteril boies plce in te ir strem becuse it is impossible to consier ll fctors. Tus, te problem is simplifie. Let us e irecte ir strem wic is crcterize by elocity, te ngle β ' between te irection of elocity n te orizontl plne n mss of te liqui roplet m moing wit elocity t n ngle γ to te ir strem n t n ngle α c from te erticl line (Figure ). 38

3 Metoologicl pproces... а) b) Figure. Clcultions (te roplet moes t n ngle α c from te erticl line to te rigt): te trjectory of reltie () n generl (b) motion of te roplet in te ir strem Te reltie elocity is etermine upon te elocity tringle rel = + cosγ (1) Te reltie elocity rel n te irection forms ngle α 1 sinγ sinα 1 = () Accelertion imprte to te roplet by ir strem in te turbulent regime is etermine by te formul (Гладков (Glko, 1991): k r S rel r rel R = = m k is te coefficient of ir resistnce, r k w rel S section of roplets (te re of te projection of te roplet on te plne wic is perpeniculr is te mile to te irection of roplet motion), (m ) krrs kw = coefficient of winge. m Let us consier te reltie motion of te roplet in te ir strem in te moble coorinte system wic is sifte by prllel motion wit strem (Figure ). We enote te components of elocity of te roplet reltie motion rel t te point A to te trjectory (3) 39

4 I.S. Кruk, Т.P Коt, О.V. Goreenko, А. Маrczuk, W. Romniuk, K. Głuszko of te reltie motion of OA x, y. Ten rel x, rel y, n te elocity components of te ir strem x = cos β ', = sin β ' (4) y Te ngle α c sowing eition of te generl elocity from te erticl line is etermine by te formul: rel x cos β ' x tg c = =. (5) sin β ' y x, y re te components of generl elocity, relte to te fixe coorinte xes (Figure,b), (m s -1 ) rel y x = rel x x, y y rel y = (6) At te beginning of te motion =, ten rel It follows from Figure 3 tt R = m k (7) w Rαx Rα cos β kwα cos β tgα c = = = (8) m g + R m g + R sin β g + k sin β R x, R y re te components of ir strem resistnce, (N). g is free fll ccelertion, (m s -1 ). αy α w α Figure 3. Te elocity eition from te erticl line wen 4 = rel

5 Metoologicl pproces... Reltie elocity pproces erticl line, wen ( reltie criticl elocity) n rel x rel y rel crit cos β ' kw cos β ' tg c crit = =. (9) sin β ' k sin β ' g rel crit Te obtine formuls sow tt te eition of te roplet motion from te erticl line ries wit te coefficient of winge of te roplet k w, ir strem elocity n ngle cnge α c. By te secon option (eition from te erticl line to te left), in te formul (9) te minus sign cnges to te plus one, n te formul becomes w cosβ ' kw cosβ ' tg c crit = =. (1) sin β ' k sin β ' g rel crit Te tir option, wen te roplet flies strigt own, ( tg = ) w α is possible wen te coefficient of winge of te roplet is k w = ; te ir strem elocity is = ; β '= 9 so te irection of te ir strem n te motion of te roplet re te sme. Teoreticl inestigtions concerning te influence of te irecte ir strem on te iniiul roplets moing t ifferent trjectories re te bsis for te justifiction of te require ngle of spry of te yrulic tomizer. All te roplets flying out of tomizers must be cugt by te ir strem, so te ngle of spry of te tomizer must be coorinte wit te ngle of te ir strem istribution to crete conitions for te eliery of roplets by te irecte ir strem n teir regulr istribution on te objects of tretment. If we consier te interction between te irecte ir strem n te ir-roplet strem generte uring te tomiztion of te process solution by te yrulic tomizers but not seprte rops, suc prmeters s coefficient of winge n te mss of te roplets cn be neglecte. Due to significnt ifference in te ir n flui ensities roplet strem soul be consiere s te ir strem. Wen usul correltions of te tomize flui mss to ir mss re consiere teir reltion is bout tousn (Абрамович, 1976). It follows tt te funmentl prmeters ffecte by te interction of strems re te mgnitue n irection of te ir strem elocity, roplet strem elocity, reltie position of te strems. To ensure eliery of te roplets to te object of tretment by te ir strem it is necessry to cnge te elocity of te ir strem. At te moment of meeting of ir-roplet n ir strems te elocity of te ltter must be significntly greter tn te elocity of te ir-roplet strem. Terefore, te irection of rops moement will cnge in te irection of te ir strem. A finlly forme integrte strem soul be uniform for regulr istribution of te process solution roplets trougout te olume of te plnts. It requires tt t te moment of meeting of te strems te ir strem must be uniform, inissoluble (Степук n Кот, 5). We efine te istnce oer wic suc kin of strem is forme. Tere re tree zones of te flow of ir troug te exust nozzles of te ir istribution system: te first zone consists of te motion of te inepenent strems, te secon one is trnsitionl (strems conerging occurs n bounry lyers mix n terefore tere is te c 41

6 I.S. Кruk, Т.P Коt, О.V. Goreenko, А. Маrczuk, W. Romniuk, K. Głuszko smooting of te elocity fiel) n te tir zone is ( combine motion of strems resembling te flow from te soli slot wit regulr elocity fiel). Distnce 1 corresponing to te re of te ouble oerlpping of ir istribution sprys is etermine by te formul: b1,5 1 =, (11) tgg were b is te xes istnce between outlet oles of te ir istribution oses, (m) 1 is te imeter of te outlet ole, (m) γ is te ngle of te lterl expnsion of te ir strem, (eg) We cn obsere te sme by te flow of te processing liqui from yrulic tomizers but reltie to quntittie istribution of te processing liqui. One cnnot spek bout te uniformity of te elocity fiel becuse eery roplet moes long its own trjectory wit its own spee in te spry. Terefore, te min criterion tt soul be obsere for te formtion of te integrte ir-roplet strem is n interflow of te sprys of te jcent tomizers (Литвинова, 1999). Te istnce t wic tis interflow occurs correspons to te secon trnsitionl zone n is etermine by te formul:,5b =, (1) α s tg b is te xes istnce between te tomizers, (m) α s is te ngle t te top of te spry of te tomizer, (eg) It is necessry to etermine te erge elocity n irection wen forming te single ir-roplet strem. It is isble to sen tem t n ngle to ec oter by externl blening of te strems. To fin te irection n elocity of te blening strems it is necessry to construct prllelogrm t te ectors of teir kinetic momentum. Its igonl E will etermine te irection of blening strems. As te istnce from te flow plne increses te mss of te strems increses n elocity ecreses. Since between mss m n elocity tere is simple inerse reltionsip, te kinetic momentum in ll sections of te strems will be constnt n equl to te initil kinetic momentum, tt is m (Кот, 5). Te mgnitue of te resultnt E is etermine by te formul: E = m cos β + m cosθ, (13) s s m s is te mss of ir strem, (kg) m is te mss of te ir-roplet strem, (kg) 4 s

7 Metoologicl pproces... is te elocity of te roplet escpe from te tomizer, (m s -1 ) β is te ngle of te eition of te ir strem from te erticl line, (eg) θ is te ngle of te eition of te ir-roplet strem from te erticl line, (eg) Ten te erge elocity of te integrte strem (te finl) is etermine by te formul: er m = s cos β + m m s + m Mss of te ir strem is etermine by te formul: m s s cosθ. (14) = Q n t, (15) s ρ f were Q is te ir iscrge in one outlet ole, (m -3 ) n is te number of outlet oles, (pcs) t is time, (s) Te ir iscrge in one outlet ole is etermine by te formul: Q π = µ. (16) 4 Te mss of te ir-roplet strem (in te initil section it cn be regre s liqui one) is etermine by te formul: m = Q nt, (17) s ρ f ρ f is te ensity of te processing liqui, (kg m -3 ) Q f is te flowrte troug te tomizer, (m s -3 ) n is te number of tomizers, (pcs) After te necessry trnsformtions we get: π rµ n cos cos β + r f Q f n θ 4 er =, (18) π rµ n + r f Q f n 4 is te initil elocity of te ir flow from te outlet oles, (m s -1 ). Te integrte ir-roplet strem before meeting wit egettie lyer oercomes certin istnce y 1. Te strem elocity t te entrnce in te egettie lyer is etermine by te formul: f 43

8 I.S. Кruk, Т.P Коt, О.V. Goreenko, А. Маrczuk, W. Romniuk, K. Głuszko,48er =, (19) y1 y1 +,145 y 1 is te istnce from te zone of te integrte strem formtion to te entrnce in te egettie lyer, (m). Formul (19) is li uner iel conitions, in rel conitions externl fctors soul be tken into consiertion. Firstly, you soul consier te influence of te nturl win on te ir-roplet strem. Seconly, conectie currents influence te ynmics of te strem. Tey pper ue to te presence of rious types of surfces on te wy of te strem (in our cse it is te ert's surfce n plnts), te temperture of wic iffers from te temperture of te ir strem. Terefore te formul (19) cn be represente in te following form: y1 =,73gy αert ( t t ) 1 αt s αt cos α +,48αer, αy1 +,145 cosα t s is te temperture on te strem xis, (eg. C) t t is te mbient temperture, (eg. C) T t is te bsolute mbient temperture, (eg. bs.) α is te ngle of te eition of te integrte strem irection from rectiliner motion, (eg) It is necessry to ensure tt te effect of moement n rottion of te plnt lees by te integrte strem trets te plnts uniformly wit pesticies. For tis purpose it is necessry to know te mximum n minimum effectie force impct on plnts. In tis cse it is mximum permissible elocity of strem entry in te egettie lyer mx wic oes not mge te plnts, n te minimum elocity wic ensures te effect of turning lees in te lower zone of te egettion lyer min. On tis bsis we cn express te eff require elocity of te strem entry onto te egettie lyer (Лысов, 1983): e y y y = = 1 ξ ( y y1 ) ξdd y is te strem elocity in te lower zone of egettion lyer, (m s -1 ), ξ is te permebility coefficient, (m -1 ), D D is te tickness of te egettion lyer, (m). e, per () (1) 44

9 Metoologicl pproces... Te following conitions soul be crrie out: > y, min eff y 1 mx. In ition per to oi estruction of roplets of te processing liqui te elocity of te entry of te integrte ir-roplet strem onto te egettie lyer must be greter tn te elocity of nturl win ( > ). y win Tking into consiertion te formul (1), te reltion (18) tkes te form (Литвинова, ): αy 1 +,145 cos α,46 e y y αer = + ξ ξ e 4 ( t t ) 47,16y1 s αy 1,145 + cos α. T cos αt α Knowing te finl elocity of te integrte ir-roplet strem it is possible to etermine te initil elocity of te flow of ir from te outlet oles of te ir istribution oses (Кот, ): αt () 4ρ cos f Q f n θ eρ =,5eρ +,5 eρ +. (3) π ρµ n cos β 4 Knowing te initil elocity of te ir flow from te oles, it is possible to clculte prmeters of te ir istribution oses of te olumetric spryers. Summry Te results of te teoreticl reserc crrie out to justify te kinemtic prmeters n reltie rrngement of te ir istributionl n yrulic systems of olumetric spryers re sown in te rticle. Te mecnism of interction of irecte ir strem generte by te ir-istributionl system wit n ir-roplet strem generte uring te tomiztion of te processing liqui by yrulic tomizers t teir outer mixing s been presente. Mtemticl reltionsips for etermintion of te require initil elocity of te ir strem, incluing te interction of te processe object n prmeters of te ir istributionl n yrulic systems re proie. References Абрамович, Г.Н. (1976). Прикладная газовая динамика. Наука, 888. Гладков, Н.Г. (1991). Зерноочистительные машины: Конструирование, расчет, проектирование и эксплуатация. Машгиз, 367. Кот, Т.П. (). Определение конструктивных параметров воздухораспределительной системы объемного опрыскивателя. Современные проблемы агротехнической проходимости и экологии сельскохозяйственных ландшафтов: Материалы науч.- техн. 45

10 I.S. Кruk, Т.P Коt, О.V. Goreenko, А. Маrczuk, W. Romniuk, K. Głuszko конф. посвящ. 7-летию со дня рождения В.А. Скотникова. Минск, окт. 1999г. Акад. аграр. наук Респ. Беларусь. Белорус. госуд. Аграр, Кот, Т.П. (5). Обоснование скоростных характеристик воздушного потока в объемном опрыскивателе. Механизация и электрификация сельского хозяйства: Межведомственный тематический сборник. РУНИП «ИМСХ НАН Беларуси», Под общ. ред. В.Н.Дашкова, Литвинова, Т.П. (1998). Эффективное использование средств механизации защиты растений. Научное обеспечение устойчивого развития Республики Беларусь: Материалы Респ. науч.- практ. конф. ГП «БелНИИМСХ», Литвинова, Т.П. (). К вопросу эффективной работы раздающего воздуховода объемного опрыскивателя. Проблемы организации управления в современном обществе: теория и практика: Материалы Респ. науч.-практ. конф. ГП «БелНИИМСХ», Лысов, А.К. (1983). Средства механизации и методы, улучшающие технологию применения пестицидов в защищенном грунте. Дис. канд. техн. наук: Ленинград Пушкин, 4. Rkowski, A., Kuboń, M. (1). Wpływ zstosownyc rozpylczy w nwożeniu olistnym n wielkość i jkość plonu nsion tymotki łąkowej (Pleum prtense L.). Inżynieri Rolnicz, 4(14), Степук, Л.Я., Литвинова, Т.П., Цехова, Т.В. (1998). Состояние и перспективы механизации химзащитных работ. Механизация и электрификация сельского хозяйства: Межведомственный тематический сборник. ГП «БелНИИМСХ»; Под общ. ред. И.С. Нагорского Степук, Л.Я., Кот, Т.П. (5). Обоснование взаимного расположения рабочих систем объемного опрыскивателя. Механизация и электрификация сельского хозяйства: Межведомственный тематический сборник. РУНИП «ИМСХ НАН Беларуси», Под общ. ред. В.Н.Дашкова, METODOLOGICZNE PODEJŚCIA PRZY UZASADNIENIU PARAMETRÓW KINEMATYCZNYCH OPRYSKIWACZY OBJĘTOŚCIOWYCH Streszczenie. Celem prcy było uzsnienie prmetrów kinemtycznyc opryskiwczy objętościowyc w celu poprwy skuteczności ostrczni roztworów procesowyc zwierjącyc pestycyy n opryskiwne obiekty. Bni teoretyczne przeprowzono n postwie prw eroynmiki i mecniki. Wyniki bń teoretycznyc przyczyniły się o sformułowni postwy l uzsnieni scemtu opowieniego ułożeni i głównyc prmetrów systemów powietrznyc i yrulicznyc opryskiwczy objętościowyc. Słow kluczowe: opryskiwnie, system powietrzny, system yruliczny, strumień powietrzekropl, tomizery 46