Template-Type: ReDIF-Article 1.0 Author-Name: J. Čupera Author-Workplace-Name: Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Author-Name: T. Šmerda Author-Workplace-Name: Faculty of Agronomy, Mendel University in Brno, Brno, Czech Republic Title: Influence of engine power and shifting mode on energy-performance parameters of tractor's set Abstract: The aim of the paper is to assess the impact of engine power and shifting mode on the parameters of a tractor used in transport operation. To meet the objective, measurements were performed with three tractors of the Case IH product line with different maximum power and with the same trailer and load that crossed a track with 21,8 km of distance. The record files saved following values: altitude, time of trip, tractor velocity, hour fuel consumption, engine speed, actual engine torque, fuel temperature, and position. The measurement results clearly show the unsuitability of aggregation of a tractor in higher performance category, resulting in the increase in its fuel consumption does not increase performance. To improve the utilization of powerful tractors, it is necessary to reduce their weight and aggregate them with more axles on the trailers in order to better use the potential power caused by possibility of more load. Keywords: transport, engine, tractor, fuel consumption, performance Journal: Research in Agricultural Engineering Pages: 47-52 Volume: 56 Issue: 2 Year: 2010 DOI: 10.17221/29/2009-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/29/2009-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201002-0001.txt Handle: RePEc:caa:jnlrae:v:56:y:2010:i:2:id:29-2009-RAE Template-Type: ReDIF-Article 1.0 Author-Name: C.O.C. Oko Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Engineering, University of Port Harcourt, Port Harcourt, Nigeria Author-Name: E.O. Diemuodeke Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Engineering, University of Port Harcourt, Port Harcourt, Nigeria Author-Name: I.S. Akilande Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Engineering, University of Port Harcourt, Port Harcourt, Nigeria Title: Design of hoppers using spreadsheet Abstract: This paper presents a spreadsheet add-in for the design of mass flow conical and wedge hoppers. The Jenike's hopper design charts for mass flow were curve fitted. The relationships obtained were used together with other relevant expressions to develop an add-in tool for the determination of the pertinent hopper design parameters (exit size, mass flow rate, semi-included angle, flow factor, and critical applied stress) in the Microsoft Excel environment. The add-in was tested with experimental data, and results obtained were in agreement with those obtained in the literature. Keywords: hopper design, curve fitting, Jenike's hopper design charts, MS Excel add-in Journal: Research in Agricultural Engineering Pages: 53-58 Volume: 56 Issue: 2 Year: 2010 DOI: 10.17221/30/2009-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/30/2009-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201002-0002.txt Handle: RePEc:caa:jnlrae:v:56:y:2010:i:2:id:30-2009-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M. Müller Author-Workplace-Name: Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: D. Herák Author-Workplace-Name: Department of Mechanical Engineering, Faculty of Engineering, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Dimensioning of the bonded lap joint Abstract: Bonded joint is a complex assembly, which creation and following use is limited by a range of factors. The primary factors are the properties of the bonded material and of the adhesive. The stress distribution in the bonded joint is substantially influenced by the bonded joint geometry and by the deformation characteristics. Laboratory experiments are intent on the above mentioned influences for bonded lap joints, which are very used in practice. The geometrical parameters of bonded joints are substantial for the constructional parameters and for costs determination. At the lower lapping length the failure of the bonded joint occurs and the maximum loading capacity of the bonded material is not fully utilized. On the contrary when using the lapping length over its optimum value the failure of the bonded material occurs. At the same time the total weight of the bonded assembly increases. Therefore it is important to determine the bonded joint optimum values which secure the reliability and which do not increase the production costs. Keywords: deformation, lapping length, epoxy adhesives, bonding technology, loading force Journal: Research in Agricultural Engineering Pages: 59-68 Volume: 56 Issue: 2 Year: 2010 DOI: 10.17221/35/2009-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/35/2009-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201002-0003.txt Handle: RePEc:caa:jnlrae:v:56:y:2010:i:2:id:35-2009-RAE Template-Type: ReDIF-Article 1.0 Author-Name: R.A. Chayjan Author-Workplace-Name: Department of Agricultural Machinery Engineering, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Author-Name: M. Esna-Ashari Author-Workplace-Name: Department of Horticultural Sciences, Faculty of Agriculture, Bu-Ali Sina University, Hamedan, Iran Title: Modeling of heat and entropy sorption of maize (cv. Sc704): neural network method Abstract: Equilibrium moisture content of maize affects its values of dehydration heat and entropy. Precise prediction of heat and entropy with regard to its equilibrium moisture content is a simple and fast method for proper estimation of energy required for dehydration of maize and simulation of dried maize storage. Artificial neural network and thermodynamic equations for computation of maize heat and entropy of sorption were used, as a new method. The artificial neural network method for prediction of the equilibrium moisture content of maize was utilized. The heat of sorption of maize is predicted by a power model. After well training of equilibrium moisture content data sets using the artificial neural network models, predictive power of the model was found to be high (R2 = 0.99). A power regression model was also developed for entropy of sorption. At moisture content above 11% (d.b.) the heat and entropy of sorption of maize decreased smoothly and they were highest at moisture content about 8% (d.b.). Keywords: maize, back propagation, entropy, isosteric heat, sorption isotherm Journal: Research in Agricultural Engineering Pages: 69-76 Volume: 56 Issue: 2 Year: 2010 DOI: 10.17221/37/2009-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/37/2009-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201002-0004.txt Handle: RePEc:caa:jnlrae:v:56:y:2010:i:2:id:37-2009-RAE Template-Type: ReDIF-Article 1.0 Author-Name: M.C. Ndukwu Author-Workplace-Name: Department of Agricultural Engineering, Michael Okpara University of Agriculture, Umuahia, Nigeria Author-Name: S.N. Asoegwu Author-Workplace-Name: Department of Agricultural Engineering, Federal University of Technology, Owerri, Nigeria Title: Functional performance of a vertical-shaft centrifugal palm nut cracker Abstract: A vertical-shaft centrifugal palm nut cracker was presented and evaluated. The cracker efficiency and kernel breakage ratio are some of the most important parameters for evaluating the cracker performance. From the result of this work, the two parameters are function of cracking speed, moisture content and feed rate. The result showed that for the lowest speed of 1,650 r/min, and the highest feed rate of 880 kg/h and for all moisture contents, the cracking efficiency was not up to 65%, therefore the efficiency increases with an increase in machine speed and a decrease in feed rate. The kernel breakage ratio ranged from 0-0.18 (0-18%) for all feed rates and moisture contents. It increased with moisture content and cracking speed, but decreased with feed rate. All the parameters determined have a linear relationship with moisture content. Keywords: kernel, cracking efficiency, feed rate, throughput capacity, shaft speed, kernel breakage Journal: Research in Agricultural Engineering Pages: 77-83 Volume: 56 Issue: 2 Year: 2010 DOI: 10.17221/28/2009-RAE File-URL: http://rae.agriculturejournals.cz/doi/10.17221/28/2009-RAE.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/rae-201002-0005.txt Handle: RePEc:caa:jnlrae:v:56:y:2010:i:2:id:28-2009-RAE