1 Analysis of collisions TECHNICAL etween white mustar SCIENCES sees or rapesees an isks... Arev.: Tech. Sc., Pap. An Rep., No 9, Y ANALYSIS OF COLLISIONS BETWEEN WHITE MUSTARD SEEDS OR RAPESEEDS AND DISKS OF A HULLING MACHINE EQUIPPED WITH CYLINDRICAL BLADES Anrzej Aners University of Warmia an Mazury in Olsztyn Faculty of Technical Sciences Department of Agricultural Engineering an Natural Raw Materials Key wors: hulling, isk of a hulling machine, sees, mustar, rape. Astract The aim of the stuy was to analyze collisions etween sees an isks of a hulling machine uring the removal of the coats of white mustars sees an rapesees. The theoretical analysis was ase on the existing moels an experimental tests. The husking process was escrie using the results of theoretical computations, which enale to etermine the contact surface area etween sees an the working elements of a hulling machine. The ifference in the surface area on a isk where collisions take place, resulting from the use of laes with a minimum or maximum iameter, is 7.5%. Due to their similar imensions an morphological structure, sees of white mustar an rape can e successfully hulle through collisions with cylinrical laes. ANALIZA ZDERZEÑ NASION GORCZYCY BIA EJ ORAZ RZEPAKU Z TARCZAMI OB USKIWACZA WYPOSA ONYMI W CYLINDRYCZNE WYPUSTKI Anrzej Aners Uniwersytet Warmiñsko-Mazurski w Olsztynie Wyzia³ Nauk Technicznych Katera In ynierii Rolniczej i Surowców Naturalnych S³owa kluczowe: o³uskiwanie, tarcza o³uskuj¹ca, nasiona, gorczyca, rzepak. Streszczenie Analizowano zerzenia miêzy nasionami a tarcz¹ o³uskuj¹c¹ zachoz¹ce poczas usuwania okrywy owocowo-nasiennej z nasion gorczycy ia³ej oraz rzepaku w o³uskiwaczu tarczowym. Analizê teoretyczn¹ przeprowazono na postawie znanych moeli oraz aañ eksperymental-
2 4 Anrzej Aners nych. Opis procesu o³uskiwania oparto na oliczeniach teoretycznych, które pozwoli³y ustaliæ powierzchniê kontaktu nasion z czêœci¹ roocz¹ o³uskiwacza. Ró nica wielkoœci pola na tarczy, na którym ochozi o zerzeñ w przypaku zastosowania wypustek o minimalnej œrenicy i zastosowaniu wypustek o maksymalnej œrenicy, wynosi 7,5%. O³uskiwanie nasion gorczycy ia³ej i rzepaku, ze wzglêu na ich poone wymiary oraz zli on¹ uowê morfologiczn¹, mo e siê oywaæ przez poawanie ich zerzeniom. Introuction In orer to increase the nutritive value of white mustar sees an foo proucts otaine from rapesees, they are hulle or fractionate. Fractionation involves mechanical ivision of sees into fractions iffering in the content of see coats an in consequence the concentrations of protein, fier an energy (BALKE, DIOSADY 000, NIEWIADOMSKI 983, SUVENDU BHATTACHARA, VASUDHA, KRISHNA MURTHY 999, VELISEK, MIKULCOVA, MIKOVA, WOLDIE, LINK, DAVIDEK 995). The esign of machines an evices for mechanical see processing requires thorough knowlege of the phenomena that occur in the working space. Such knowlege is also inispensale in the case of mechanical see coat removal (ANDERS 003, GRZELAK 996, SZWED, LUKASZUK 004). Numerous authors have analyze the phenomena taking place uring mechanical see hulling an see coat reaking (KWIETNIAK, KWIETNIAK 989, LASKOWSKI, LYSIAK 993, MIESZKALSKI 999, SARNIAK 997). In the case of rapesees, mechanical coat separation allows to eliminate harmful glucosinolates an improve the quality of oil use for ietary purposes, whereas hulle white mustar sees can e use for the prouction of seasonings an spices. Aim of the stuy The aims of the stuy were to analyze a collision-ase metho of coat removal from sees of white mustar an rape, an to calculate the surface area on a isk where sees come into contact with cylinrical laes in the working space of a isk-type hulling machine. Methos Experimental tests were conucte to remove the coats of white mustar sees an rapesees. The experimental materials comprise sees of white mustar an rape var. Sponsor, store inoor in plastic ags at a constant temperature of 8 C an air humiity of aout 85%. Prior to tests the sees
3 Analysis of collisions etween white mustar sees or rapesees an isks... 5 were separate on a pneumatic separator with a vertical aspiration airtrunk, to eliminate impurities an roken sees. The moisture content of sees range from 6.5 to 8.5%, an was etermine accoring to the Polish Stanar PN-EN ISO 665:999. The working space of a hulling machine is compose of a top cover, a cylinrical casing an a hulling isk. The isk is equippe with cylinrical laes, f =, 3, 4 mm, place raially (Fig. ). The sees were gravitationally supplie to the working space through a fee hopper in the top a Fig.. Working isk of a laoratory isk huller: a view of a isk, upper eges of the laes of a hulling isk cover. The isk, 40 mm in iameter, was rotating at a constant angular velocity of w = 738 ra/s. A etaile escription of the experimental methos an results is given elsewhere (MIESZKALSKI, ANDERS 00, 003). The size of sees of white mustar an rape, aopte for theoretical calculations, was.4 mm to.8 mm (NIEWIADOMSKI 983). In orer to perform a more etaile theoretical analysis of collisions etween sees an the hulling isk, the following simplifications were mae: the sees were treate as homogenous spheres, the interactions etween sees an the aeroynamic rags of see motion in the working space of a hulling Disk no. Disk iameter D (mm) Numer of rows of laes place raially Construction parameters of a Numer of laes place raially in a row hulling isk Blae height (mm ) Outer iameter of a cylinrical lae w (mm ) T a l e Distance etween laes m (mm)
4 6 Anrzej Aners machine were ignore. It was also assume that the surface areas of sees an working elements are smooth an that the sees supplie to the working space form an orere layer. Strains of the working elements of a hulling machine were isregare. In orer to etermine similarities in the morphological structure of the sees use in the experiment, 0 mustar sees an 0 rapesees were selecte from the samples prior to hulling. Right sections along cotyleons were mae, an photographs were taken using a igital camera an a microscope, at 60x magnification. Results Sees fall into the working space of a hulling machine uner the influence of gravitational force, through a slot (length = 5 mm) in the fee hopper. Length permits continuous see feeing to the isk. The sees reoun against the laes an the top cover of the working space. It was assume that the sees falling own can come into contact with the laes at various points on the isk a h m h m w w Fig.. Sees falling own onto the cylinrical laes of a isk: outlet of the fee hopper, lae; outlet length, w lae iameter, h istance etween the fee hopper an the upper ege of a lae, lae height, m istance etween lae axes (Fig. ). See falling takes place within segment h, an then the sees touch upon the working elements. Various outer iameters of laes an istances etween laes on a isk provie conitions for ifferent types of contact etween laes an sees uring the hulling process (Fig. 3). Blae iameters affect the contact surface area
5 Analysis of collisions etween white mustar sees or rapesees an isks... 7 a c w w m m m3 w3 Fig. 3. Contact etween sees an cylinrical laes with ifferent outer iameters (top view): a w = 4 mm, w = 3 mm, c w3 = mm; m, m, m 3 istance etween laes, sees, cylinrical laes etween sees an laes as well as stresses within see coats. The greatest stresses are oserve when sees are struck centrally y rotating laes. The total surface area of a hulling isk, over which contact etween sees an laes occurs, varies epening on the instantaneous position of the working element an a see (Fig. 4). This area can e calculate using formulas, an 3. The area over which a see strikes against the isk lae is: A = p w AB, AB = hw - () where: w outer iameter of a lae (mm), lae height (mm), see iameter (mm). It was assume that the area over which a see strikes against the isk ase correspons to a circular sector iminishe y the areas of orthogonal projections of the contours of isk laes: p æ ö ( R -( R -) )- ç ( + + ø j p B = w w ) è4 where: j =30 angle etween two neighoring rows of laes, R raius of the hulling isk (mm), length of the fee hopper slot (mm), = 80 angle at which sees come into contact with laes. ()
6 8 Anrzej Aners 3 h A w B C V t D A R w O c B w O 4 m O a O 3 Fig. 4. Area of contact etween sees an cylinrical laes of a hulling isk: see, laes, 3 cover: A B segment representing contact etween a see an the lateral surface of a lae, C D segment representing contact etween a see an the surface area of a isk The total surface area etween neighoring rows of laes place raially, where sees strike against the hulling isk, is: O = A + B (3) When actual imensions of the hulling isk an sees are sustitute into the aove formulas, we otain the surface area of a isk where see collisions take place (Fig. 5).
7 Analysis of collisions etween white mustar sees or rapesees an isks surfoce area (mm) A B C D E F G H I Fig. 5. Contact surface area etween sees an the hulling isk: A w = mm, =.8 mm, B w = mm, =.3 mm, C w = mm, =.5 mm, D w = 3 mm, =.8 mm, E w = 3 mm, =.3 mm, F w = 3 mm, =.5 mm, G w = 4 mm, =.8 mm, H w = 4 mm, =.3 mm, I w = 4 mm, =.5 mm An analysis of Figure 5 shows that the ifference in the surface area on a isk over which collisions take place, resulting from the use of laes with a iameter of mm an 4 mm an sees with a iameter of.4 mm an.8 mm respectively, is 7.5%. During the hulling of white mustar sees an rapesees,.4 mm to.8 mm in iameter, on a isk equippe with laes mm in iameter, the surface area over which sees strike against isk elements is 73.3 mm an 6.0 mm respectively. Photographs of see sections taken uner the microscope show that sees of white mustar an rape have similar structure. The sees are covere y coats see iameter (mm) a Fig. 6. See sections: a rapesee, white mustar see, see coat, cotyleons insie which there are four cotyleons an an emryo, loosely connecte with each other (Fig. 6). The see coat is not permanently connecte with the inner morphological parts of a see. See sections an photographs taken uner the microscope reveal places where the coat comes off the inner cotyleons.
8 0 Anrzej Aners Conclusions. A theoretical analysis of the size of the areas on a hulling isk over which sees strike against laes enale to esign a isk permitting a high numer of collisions necessary to remove the coats of white mustar sees an rapesees.. Due to their similar imensions an morphological structure, sees of white mustar an rape can e hulle through collisions with the working elements of a isk (cylinrical laes). References ANDERS A Rapesee coat removal using isks equippe with cylinrical laes. Technical Sciences, 6: BALKE T.D., DIOSADY L. L Rapi aqueous extraction of mucilage from whole white mustar see. Foo Research International, 33: GRZELAK E Postawy uerzeniowego rozraniania materia³ów. Prz. Mech., 4. KWIETNIAK M., KWIETNIAK P Urz¹zenia o rozraniania nasion rzepaku i pneumoseparacji œruty rzepakowej. Przegl. Zo -M³yn., 9: 3-6. LASKOWSKI J., YSIAK G Wp³yw wilgotnoœci na efekt o³uskiwania nasion rzepaku na mlewniku walcowym. III International Conference on Crumlers Engineering, Bygoszcz. KBN Wy. TNOiK, Bygoszcz: 7-3. MIESZKALSKI L., ANDERS A. 00. Wp³yw parametrów konstrukcyjnych i kinematycznych tarcz o³uskiwacza na skutecznoœæ o³uskiwania nasion rzepaku. Prolemy In ynierii Rolniczej, : MIESZKALSKI L Matematyczne moelowanie procesu o³uskiwania nasion. Rozprawy i Monografie, Wyawnictwo ART, Olsztyn. NIEWIADOMSKI H Technologia nasion rzepaku. PWN, Warszawa SARNIAK M Metoa szacowania skutecznoœci o³uskiwania nasion rzepaku. Politechnika Warszawska, Wyzia³ Buownictwa, Mechaniki i Petrochemii, P³ock (praca oktorska). SUVENDU BHATTACHARA, VASUDHA N., KRISHNA MURTHY K.S Rheology of mustar paste: a controlle stress measurement. Journal of Foo Engineering, 4: SZWED G., UKASZUK J Uszkozenia nasion rzepaku jarego w warunkach zia³ania si³ uarowych. Acta Agrophysica, 4(3): VELISEK J., MIKULCOVA R., MIKOVA K., WOLDIE K.B., LINK J., DAVIDEK J Chemometric investigation of mustar see. Leensmittel-Wissenschaft un Technologe, 8: Translate y Aleksanra Poprawska Accepte for print