Power circulation in driveline system when the wheels of tractor and trailer are driven

In off-road “tractor–trailer” vehicle combinations, the trailer can be equipped with one or more driving wheels. The distinguishing feature of vehicles with two or more driving axles is distribution of total power between the driving wheels. In machines with several driving axles, kinematic mismatch between theoretical wheel speeds nearly always takes place. The wheels of tractor and trailer can slip uniformly and differently, some of them may even slide. It is unfortunate when the wheels slide, as power circulation takes place. In this paper, power circulation of a vehicle composed of a tractor and trailer having driving wheels and driving wheels’ interaction with soil is investigated. The conclusion is that in a vehicle composed of two machines having two driven axles each, circulation of power can be avoided or reduced by turning off one driving axle in the machine, which delivers more power and has advancing driving wheels

Tractor engine load and fuel consumption in road construction works

Tractor load influences engine work parameters having an influence on the working economy and productivity of the complete tractor aggregate. The operational economy and productivity of the tractor is mostly evident when its engine power is utilized at least at 80% and engine speed is as low as possible. The paper analyses the engine parameters of tractor Massey Ferguson MF 8480 during the operational period of road construction works. Control tests on the parameters of the engine load of the tractor engine in combination with the employed milling equipment WS 2500 produced by the company ‘Wirtgen’ were performed. The study was carried out using engine load tables and graphs collected and stored in the so called ECU Load Profileintegrated in Electronic Engine Control Units. Theoretical analysis was made and an equation presented to establish the relation between engine power, engine speed and the quantities of cyclic fuel consumption. The study results present the distribution graphs of work time and fuel consumption at different engine speed during the operational period. The paper also indicates engine load and fuel consumption graphs of the tractor in combination with milling equipment. The article has also disclosed that the analysis of engine speed and load modes using information obtained from tractor‐integrated digital microprocessors reveals the operation quality of the tractor. First published online: 10 Feb 201

Dependencies of the lead of front driving wheels on different tire deformations for a MFWD tractor

Tractors are the main machines in agricultural production processes. Agricultural tractors commonly employ a four-wheel drive transmission. To reach maximum efficiency in production works, tractors are loaded by as high thrust as possible. The consequence of it, quite often, is that the slippage of driving wheels grows to the limit that is not allowed. To reduce the slippage, various ways are pointed out in terramechanics. One way is to increase the tractor’s weight by adding ballast. The other way is to increase the contact area between tires and the supporting surface. The slippage can be also reduced with traction control and other relevant systems. These methods, which help to reduce slippage, also affect tire deformation. When proportion of tires deformation is not the same as proportion of their sizes, the consequence is change of the lead of front wheels. In this paper analysis is presented, how the lead of front wheels affects the work of MFWD tractor in different conditions. Test results are presented for a MFWD tractor, how the lead of front wheels varies depending on deformation ratios between front and rear tires. For a MFWD tractor, values of deformation ratio between front and rear tires were determined, which ensured effective and which produced unreasonable values of lead of front wheels. First published online: 17 Jul 201

Analysis of variation in straw briquet density during storage

Numerio antraštė: Biosystems engineering and processes in agriculture : 25-26 September, 2008, [Raudondvaris]While using the waste of agricultural plants for fuel, an issue of its preparation for burning arises. Much work in this field is done in Germany, England, Denmark, Hungary and Poland. In Germany 20 % of all amount of grown straw is used for energy production which equals to 1.5 million tons of oil products [1,2]. The energy value of briquettes straw ranges from 12 to 14.3 MJ/kg. Therefore, while using straw briquette for fuel we would get only slightly smaller amount of energy compared with firewood, the energy value of which is 15.5 MJ/kg [3–5]. In many cases wood sawdust is pressed. At present most often 50–60 mm diameter briquettes, the length of which is 5–20 cm [3], or square ones are produced. Pelleted fuel is common in the Western European countries. Though special equipment is needed for heating and production cost is much higher, pellets are widely used, especially in Denmark and Sweden. The work objective and tasks are to establish the optimum length of straw chaff, its moisture and pressure force for producing straw briquettes intended for burning in heating boilers and to evaluate their density variation during storageVytauto Didžiojo universitetasŽemės ūkio akademij

Grain drying in variable air flow

Straipsnyje aprašomas naujas energijos taupymo metodas džiovinant grūdus kintamu oro srautu. Metodo esmė yra tai, kad džiovinimo metu mažėjant drėgmės atidavimui iš grūdų yra mažinamas ir per grūdus praeinančio oro debitas. Reguliuojant pučiamo oro kiekį aktyviosios ventiliacijos įrenginiuose, geriau panaudojamos oro absorbcinės savybės ir atitinkamai sumažinama ventiliatoriaus naudojama galia. Elektros sunaudojimas (palyginus šį džiovinimo būdą su tradiciniu, kai oras tiekiamas nuolat) gali sumažėti iki 40 %. Tyrimams naudoti ‘Roland’ miežiai, kurių pradinis drėgnis 25 ir 30 %. Nustatyta, kad optimalus pradinis oro debitas 800 m3/(t · h). Grūdų džiūvimo metu oro debito mažinimas apibrėžiamas lygtimi y = 969,85e–0,0114x, R2 = 0,8088. Pateikta sukonstruoto ir pagaminto eksperimentinio įrenginio schema. Nustatytas oro srauto intensyvumas ir drėgmės absorbavimo dinamika džiovinamų grūdų sluoksnyjeVytauto Didžiojo universitetasŽemės ūkio akademij

Reseach pressed parameters stra w and grass mixture briquets

Straipsnyje nagrinėjamas šiaudų ir žolės mišinių tinkamumas presuoti į briketus norint juos panaudoti kūrenimui. Darbo metu nustatyti briketų gamybos iš šiaudų ir žolių mišinių optirnalūs presavimo parametrai: optimalus šiaudų ir žolės mišinių drėgnis, slėgio jėga, reikalinga supresuoti šiuos mišinius į briketus. Tyrimams buvo panaudoti žieminię kviečių veislės 'Zenta' šiaudai bei pievų ir ganyk:lų žolė. Bandymai atlikti presuojant šiaudų ir žolės mišinius hidrauliniu presu į 40 mm skersmens briketus. Tyrimams buvo naudojami smulkinti šiaudų ir žolės mišiniai susmulkinti į 10 mm frakcijas. Šiaudų ir žolės mišinių drėgnis svyravo nuo 10 % iki 14 %. Bandyta specialiai pagamintu hidrauliniu presu, kuris presavo šiaudus į cilindrinius 40 mm skersmens briketus. Laboratorinių bandymų metu presuoti 'Zenta' veislės kviečiu šiaudai, kurių drėgnis siekė nuo 10 iki 14 %. Smulkintų šiaudų pjaustinio ilgis svyravo nuo 1 iki 10 mm. Pagamintų briketų tankis siekė iki 900 kg/ nr'. Nustatyta slėgio jėga, reikalinga supresuoti šiaudų ir žolės mišinius į briketus, priklausomai nuo briketų tankioThis article analyses possibilities of pressing straw and grass mix into briquettes. This briquettes suitability for buming small power stove. Huge influence on pressing is made by optimum moisture of pressed mass, length of chopped straw and grass mix, and pressing force, parameters of a granule or briquette, their density. Trials were performed by a specially bui lt hydraulic press which pressed straw into round briquettes of 40 mm diameter. During laboratory trials straw of 'Zenta' variety wheat and grass mix was press ed, the moisture of which ranged from 10% to 14%. The length of chopped straw varied from 1mm tolO mm. The density of produced briquettes reached up to 900 kg/nr', Chopping of straws had great influence upon pressing them into briquettes. Chopping fractions of 15 mm were investigated. Pressing force required for pressing straw into briquettes depending on achieved briquette density has been establishedVytauto Didžiojo universitetasŽemės ūkio akademij

Energy saving grain drying method

Numerio antraštė: Development of agricultural technologies and technical means in ecological and energetic aspects : 14-15 September 2006The article describes a new energy saving method when drying grain. A grain drying technology while changing the air flow blown through grain has not been investigated in Lithuania. The idea of the method is that when moisture release from grain decreases, air discharge going through the grain is reduced as well. “Roland” variety of barley with 25 % and 30 % moisture content was used in the trial. It was dried with a changeable air discharge in order to maintain absorption qualities. The grain is started to be dried and the air flow is reduced in the process of drying as relative moisture content of passing through air decreases. It has been established that the optimum initial air discharge is 800 m3/(t•h). During grain drying air discharge is reduced and it can be described by equation , R2 = 0.8088. A scheme of designed and manufactured trial device is presented. Intensity of air discharge has been established. Dynamics of moisture absorption in a layer of dried grain have been establishedVytauto Didžiojo universitetasŽemės ūkio akademij

Grain drying by use of changeable air flow method

Vytauto Didžiojo universitetasŽemės ūkio akademij

The research grain drying by variable air flow

Straipsnyje nagrinėjami "Roland" veislės miežiai, kurių pradinis drėgnis 25% ir 30%. Jie buvo džiovinami kintamu oro srautu, norint išnaudoti oro sorbcines savybes. Grūdai pradedami džiovinti ir oro srautas džiovinant mažinamas, mažėjant iš grūdų išeinančio oro santykiniam drėgniui. Nustatytas oro srauto intensyvumas, dregmės absorbavimo dinamika džiovinamų grūdų sluoksnyjeIn the article is analyzed the "Roland" species barley, which initial moisture is 25% and 30%, they were dried by wariable air flow, in order to use fully the air absorbtions features. Grain is started to dry and air flow during the drying process is reduced, while the grain output humidity is declining. It is established the air flow intensity. Also it is established the humidity absorption dynamics in grain layer, which is dryingVytauto Didžiojo universitetasŽemės ūkio akademij

Grain drying in variable air flow

Straipsnyje aprašomas naujas energijos taupymo metodas džiovinant grūdus kintamu oro srautu. Metodo esmė yra tai, kad džiovinimo metu mažėjant drėgmės atidavimui iš grūdų yra mažinamas ir per grūdus praeinančio oro debitas. Reguliuojant pučiamo oro kiekį aktyviosios ventiliacijos įrenginiuose, geriau panaudojamos oro absorbcinės savybės ir atitinkamai sumažinama ventiliatoriaus naudojama galia. Elektros sunaudojimas (palyginus šį džiovinimo būdą su tradiciniu, kai oras tiekiamas nuolat) gali sumažėti iki 40 %. Tyrimams naudoti ‘Roland’ miežiai, kurių pradinis drėgnis 25 ir 30 %. Nustatyta, kad optimalus pradinis oro debitas 800 m3/(t · h). Grūdų džiūvimo metu oro debito mažinimas apibrėžiamas lygtimi y = 969,85e–0,0114x, R2 = 0,8088.Pateikta sukonstruoto ir pagaminto eksperimentinio įrenginio schema. Nustatytas oro srauto intensyvumas ir drėgmės absorbavimo dinamika džiovinamų grūdų sluoksnyjeA new energy saving method for grain drying is presented. The grain drying technology, changing the airflow blown through grains, has never been investigated in Lithuania, since there were no equipment to change the whirls of three-phase changing current electric engines. Now, when the equipment to change the frequency of the three-phase current, is available, there is a possibility to regulate the spinning frequency of grain blowers. The essence of the method is that during the drying period, when the moisture removal decreases, the air debit flowing through grains is also reduced. Barley ‘Roland’ grains of the initial moisture 25% and 30%, were used in the study. They were dried by changing air debit, in order to avail the absorption features of the air. When grain starts to dry, the airflow is reduced during the drying period, and the relative humidity flowing out of grains also decreases. The optimal initial air debit was 800 m3/t · h. The reduction of air debit during the grain drying period is expressed by the function y = 969.85e–0,0114x, R2 = 0.8088.A scheme of the constructed and produced experimental equipment is presented. The intensity of airflow is established. The dynamics of moisture absorption in the drying grain layer is establishedLietuvos žemės ūkio universiteto Žemės ūkio inžinerijos instituta