The Effect of the Design of the Spreading Device on the Working Widht and Evennes of Spreading in the Case of Centrifugal Spreaders

247 Bulle in UASMV Ag icul u e, 66 (1)/2009 P in ISSN 1843-5246; Elec onic ISSN 1843-5386 The E ec o he Design o he Sp eading De ice on he Wo king Wid h and E ennes o Sp eading in he Case o Cen i ugal Sp eade s E zsébe ANCZA, Ágnes GINDERT-KELE, Zol án HAGYMÁSSY Facul y o Ag icul u al Sciences, Uni e si y o Deb ecen Abs ac . Today a signi ican pa o solid e ilize s a e sp ead by cen i ugal sp eade s all o e he wo ld, and i is gene al in Hunga y as well. Thei popula i y is due o hei mul iple usage, simple cons uc ion, low main enance demand, easy ope a ion and low p ice. The ield pe o mance o spinning disc e ilize sp eade s basically depends on wo ac o s: he o wa d speed and he wo king wid h. As he e a e some echnical, ope a ional and ene ge ic limi s o inc easing he o wa d speed, my se objec i e in his s udy is o make u he de elopmen s ela ed o hese machines’ wo king wid h. Rising he wo king wid h one can lowe he damage o he soil, he cos s o ope a ion, and a he same ime he a ea o o e lapping alling on uni a ea, and so he une enness o sp eading. Une en e ilize dis ibu ion will esul in yield loss. The main objec i es o he examina ions p esen ed he eina e we e o explo e he ela ionships be ween he pa ame e s conside ed impo an om he abo e men ioned poin o iew. Keywo ds: cen i ugal sp eade , sp eading de ice, une enness o sp eading, wo king wid h. INTRODUCTION The nu ien con en o he soil de e mines he quan i y and he quali y o he yield. In Hunga y, a i icial e ilize s a e dominan in nu ien supply, as he o ganic manu e p oducing capaci y o he coun y can only co e one i h (0.5 animal /ha) o o al nu ien demand. Besides he quan i y and p opo ion o he agen s, de e mined by he demand o he plan , he high quali y o applica ion is ge ing mo e and mo e impo an . Today a signi ican pa o solid e ilize s a e sp ead by spinning disc e ilize sp eade s all o e he wo ld, and i is gene al in Hunga y as well. Thei popula i y is due o hei mul iple usage, simple cons uc ion, low main enance demand, easy ope a ion and low p ice. The ield pe o mance o spinning disc e ilize sp eade s basically depends on wo ac o s: he o wa d speed and he wo king wid h. As he e a e some echnical, ope a ional and ene ge ic limi s o inc easing he o wa d speed, my se objec i e in his s udy is o make u he de elopmen s ela ed o hese machines’ wo king wid h. Rising he wo king wid h one can lowe he damage o he soil, he cos s o ope a ion, and a he same ime he a ea o o e lapping alling on uni a ea, and so he une enness o sp eading. Une en e ilize dis ibu ion will esul in yield loss. The mos signi ican ac o s a ec ing he wo king wid h o cen i ugal e ilize dis ibu o s and he e enness o hei sp eading a e: he physical p ope ies o applied e ilize s; he olume o e ilize low; he loca ion o eeding on he su ace o he spinning disc ; he numbe o blades; he leng h o blades; he shape o blades; he pi ch angle o blades wi h he di ec ion o he adius; he discs heigh posi ion; he axial dis ance o he discs; he numbe o o a ion o he discs; he diame e and he shape o he discs. F om he abo e lis ed ac o s I s udied he loca ion o dosage on he su ace o he spinning disc, he numbe , he leng h, he pi ch angle o blades in he unc ion o wo king 248 wid h and sp eading e enness. All he o he ac o s we e cons an . I did no examine he design o he eede de ice, bu he e enness and he symme y o dosage we e egula ly checked. I pe o med my examina ions on he measu ing ack o he Depa men o Machine y, Facul y o Ag icul u al Sciences, Deb ecen Uni e si y. The measu ing ack capable o pe o m ou -doo s measu emen s, and so du ing he examina ions we ied o elimina e he e ec s o ex e nal in luences (i egula i ies in ield su ace, oge he wi h inclina ion o e ain, he wind, e c.) MATERIALS AND METHODS The measu ing ack consis s o a conc e e ack and a ow o collec ing ays, se up pe pendicula ly o he ack. The a ea o he measu ing ays is 500x500 mm squa e and hey a e equipped wi h a g id o p e en pa icles om escaping. The line o he ays is aised abo e he g ound o 800 mm. Unde he measu ing ays he e a e numbe ed collec ing boxes. A e epea ing he es h ee imes he boxes a e collec ed and he quan i y o hei s is measu ed wi h an accu acy o 0.1 g. The alues a e ed in o a compu e and wi h he help o a ge so wa e he compu e de e mines he main quali a i e cha ac e is ics o he sp eading de ice. Depending on he sp eading wid h, de e mined by he pa ame e s o he applied sp eading de ice, I used he measu ing ack om 25 o 40 me e s. To cha ac e ize he ans e sal une enness o sp eading, in compliance wi h in e na ional s anda ds, I used he coe icien o a ia ion (CV): 1n xx x 100 CV n 1i 2 ii i - )( ∑ = − = %, whe e: xi is he a e age o e ilize quan i ies om h ee eplica ions on one measu ing si e; i x is he a e age o g ain olume om h ee eplica ions on all he measu ing si es; n is he numbe o measu ing si es. Pe missible alue o CV is 15% (MSZ-05-10. 0283). The wo-disc sp eade o he expe imen al machine can be equipped wi h wo and h ee-bladed spinning discs. The blades a e o di e en leng h. The pi ch angle o he blades is adjus able in h ee s ages, acco ding o Fig.1. The angle o he sp eading blade included wi h he adius in A posi ion is 40 o , in B posi ion 35 o and in C posi ion 30 o backwa d o he di ec ion o o a ing. In he case o wo blades he longe blade is indica ed i s , and he sho e a e wa ds, e.g. A/A. In he case o h ee blades he long blade is indica ed i s , han he medium, and han he sho one, e.g. A/B/C. The e is a de ice on he expe imen al machine which is o adjus he loca ion o eeding on he su ace o he spinning discs in se e al di ec ions. The adjus able eeding loca ions can be seen in Fig.2. La e hese a e indica ed as e.g. A9, B8. 249 Fig.1 Possibili ies o adjus ing he pi ch angle o blades Fig.2 Loca ions o eeding ela ed o he su ace o he spinning disc (Mene i ány: Di ec ion o a elling; Fo gási ány: di ec ion o o a ion o he spinning disc) A eeding loca ion can also be gi en wi h i s coo dina es, o ; ψ o , as i is shown in Fig.3. Fig.3 Coo dina es o he eeding loca ions 250 RESULTS AND DISCUSSIONS 1. The wo king wid h in he unc ion o he eeding loca ion The diag ams, shown in Fig.4 illus a e he ela ion be ween he coo dina es o he eeding loca ions ( o ; ψ o ) and he ob ained wo king wid h: i can be seen clea ly, ha he e is a linea connec ion in he gi en di ec ion. Dec easing he alues o o and ψ o in he ma ked di ec ion, he wo king wid h will inc ease. When o he e ilize ypes we e used, and when h ee-bladed disc was examined, he same esul was ob ained. Fig.4 Rela ion be ween he coo dina es o eeding loca ions and he ob ained wo king wid h 2. The e ec o he pi ch angle o he blades on he wo king wid h When he blades we e se in A/A posi ion (Fig. 1.) he sp eading cu e had wo minimal alues, i.e. a he wo king wid h o 12 me e s, and 25 me e s (Fig. 5), bu 25 me es can no be conside ed as wo king wid h, because he une enness is highe han 15%. 251 Fig. 5 T ans e sal sp eading pa e n and sp eading cu e on C2 eeding loca ion, in A/A blade posi ion The expe imen s we e ca ied ou wi h wo- bladed discs, and he pi ch angle o bo h blades was se in h ee posi ions. Acco ding o he esul s, he al e a ion o he pi ch angle o he longe blade has a g ea e e ec on he ans e sal sp eading pa e n, and so on he wo king wid h. Se ing he blades in B/A posi ion ( he longe blade in B, he sho e one in A posi ion), he wo king wid h inc eased om 12 me e s o 28 me e s ( ig. 6). l Fig.6 Filling in he cen e o he ans e sal sp eading pa e n, adjus ing he pi ch angle o he longe blade 3. Inc easing he wo king wid h by al e ing he leng h o he sp eading blades Acco ding o he basic lows o physics, by inc easing he leng h o he blades we can inc ease he cas dis ance o he e ilize pa icles, and so he sp eading wid h can inc ease. Inc easing he leng h o he blades he discha ge eloci y o pa icles will inc ease. Howe e , he e a e cons uc ional limi s o inc easing he leng h o blades. Then leng h o he blades was al e ed in di e en combina ions. Acco ding o he measu emen s, conside ing he wo king wid h and he e enness o sp eading, he 350/300/300 mm leng h combina ion was be e han he 350/350/350 mm combina ion. Fu he inc easing he leng h o one blade he expe imen s we e pe o med by using h ee combina ions o blade leng hs. Acco ding o he expe imen esul s he mos ad an ageous is o use h ee blades o di e en leng h. By using he 400/350/300 mm blade leng h combina ion on an op imal eeding loca ion we we e able o each a ela i ely la ge wo king wid h (e.g. on B4 eeding loca ion, 26 me es wo king wid h). 252 4. The e ec o he numbe o he blades on he alue o he wo king wid h and he e enness o sp eading Two conclusions we e d awn acco ding o he expe imen esul s: he e is a linea ela ion be ween he coo dina es o he eeding loca ion ( o ; ψ o ) and he ob ained alues o wo king wid h, in bo h cases, using wo o h ee blades. The ob ained wo king wid h was always la ge by using wo blades (Fig. 7). 0 5 10 15 20 25 30 A6 A5 A4 A3 Wo king wid h [m] Feeding loca ions Wo king wid hs wi h 2 and 3 blades 2 blades 3 blades Fig.7 The ob ained wo king wid hs by using wo and h ee blades REFERENCES 1. Ancza, E. (2005). Theo e ical and p ac ical ela ions o inc easing he wo king wid h o cen i ugal e ilize sp eade s. Doc o al disse a ion. Deb ecen 2. Csizmazia, Z. – Polyák, N. I. (1997). Design and Con ol Ques ions o Ro a y Disc Fe ilize Sp eade Machines. Hunga ian Ag icul u al Enginee ing. No 10. 22-24. p. 3. Csizmazia, Z. (1993). Vizsgálóbázis ejlesz ése mű ágyaszó ó gépekhez. Já mű ek, Épí őipa i és Mezőgazdasági Gépek. 40. é . 3. sz. 109-112. p.