Tag Archives: fuel consumption

xxx M. Pexa, J. Čedík, F. Kumhála and R. Pražan
Comparison of mechanical and electric drive of mulcher
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Comparison of mechanical and electric drive of mulcher

M. Pexa¹*, J. Čedík¹, F. Kumhála² and R. Pražan³

¹Czech University of Life Sciences, Faculty of Engineering, Department for Quality and Dependability of Machines, Kamýcká 129, CZ16521, Prague 6, Czech Republic
²Czech University of Life Sciences, Faculty of Engineering, Department of Agricultural Machines, Kamýcká 129, CZ16521, Prague 6, Czech Republic
³Research Institute of Agriculture Engineering, Drnovská 507, CZ161 01, Prague 6, Czech Republic
*Correspondence: pexa@tf.czu.cz

Abstract:

The contribution is focused on comparison of mechanical and electric drive of mulcher with vertical axis of rotation by means of mathematical model. The mulcher has working width of 6 m and it is usually aggregated with tractor of minimal power of 150 kW. On the test plot the torque and power transferred trough the tractor PTO, fuel consumption and the production of gaseous emissions components were monitored. This field measurement served as a basis for modelling as well as measured complete characteristics of the combustion engine of the tractor John Deere 7930. As a main base for the modelling the record of real operation of the tractor with mulcher was used. Then, in the software product MathCad the operation of the tractor with mechanical and electrical drive of the mulcher was modelled. In the case of the electrical drive of the mulcher the tractor with internal combustion engine, connected to generator was taken into consideration. Due to overall lower efficiency of the electrical drive with generator, worse values of the fuel consumption and emissions production in comparison with mechanical drive were reached in case of electric drive. At hypothetical use of batteries (100% electro-powered tractor) and when the energy mix at Czech Republic is taken into consideration, it is possible to reach the quarter values of emissions production in comparison with combustion engine.

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xxx O. Šařec and P. Šařec
Results of fifteen-year monitoring of winter oilseed rape (Brassica napus L.) production in selected farm businesses of the Czech Republic from the viewpoint of technological and economic parameters
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Results of fifteen-year monitoring of winter oilseed rape (Brassica napus L.) production in selected farm businesses of the Czech Republic from the viewpoint of technological and economic parameters

O. Šařec* and P. Šařec

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Machinery Utilization, Kamycka 129, CZ165 00 Prague 6 – Suchdol, Czech Republic
*Correspondence: sarec@tf.czu.cz

Abstract:

The paper presents field trials focused on technological and economic comparison of conventional tillage (CT) and reduced tillage (RT) technologies of soil cultivation and drilling of winter oilseed rape (Brassica napus L.). During fifteen production years starting in 2001/02, trials were set up in 520 fields of around 40 farm businesses located in all of the districts of the Czech Republic. With respect to average seed yields, no significant differences were proved with respect to tillage systems, to the application of organic fertilizers and to the fertilization during sowing. Irregular distribution of trial fields into the individual production areas influenced the outcomes thou. Concerning winter rape seed yields, costs per production unit, and earnings per hectare, the most suitable production area proved still to be the potatoes one, but particularly over the recent period also beet production area. The corn production area produced, despite some exceptions, worst results. Over the fifteen-year time, the average oilseed rape yield of all 520 monitored fields was 3.72 t ha–1. Reduced tillage attained average yield of 3.73 t ha–1, i.e. matched almost exactly the one of 3.70 t ha–1 attained by conventional tillage. Unit production costs realized by conventional tillage surpassed by 4.1% those gained by reduced tillage. Related earnings per hectare were on the other hand lower by 17.0%. With respect to fuel and labour consumption, reduced tillage brought significant savings reaching in average 20.2%, respectively 24.0%. In terms of yields, reduced tillage with deeper soil loosening proved repeatedly favourable results.

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964–970 G. Birzietis,, V. Pirs, I. Dukulis and M. Gailis,
Effect of commercial diesel fuel and hydrotreated vegetable oil blend on automobile performance
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Effect of commercial diesel fuel and hydrotreated vegetable oil blend on automobile performance

G. Birzietis¹,*, V. Pirs¹, I. Dukulis¹ and M. Gailis¹,²

¹ Latvia University of Agriculture, Faculty of Engineering, Motor Vehicle institute, 5 J. Cakstes boulv., LV-3001 Jelgava, Latvia
² Riga Technical University, Faculty of Mechanical Engineering, Transport and Aeronautics, Department of Automotive Engineering, Viskalu 36, LV-1006 Riga, Latvia
*Correspondence: gints.birzietis@llu.lv

Abstract:

The new fuel ‘Pro Diesel’ that contains hydrotreated vegetable oil (HVO) was recently introduced in Baltic market. It raised some interest on performance of the new fuel among fleet and individual consumers. The authors evaluated and compared performance of modern M1 class automobile, using regular fossil diesel fuel and Pro Diesel fuel.
Torque, power and fuel consumption of the vehicle have been evaluated on chassis dynamometer, in steady state and driving cycle mode.
Depending on test conditions, engine power and torque was increased up to 2%, and fuel consumption reduced up to 3.9%, when diesel fuel/ HVO blend was used.

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1162–1169 B. Peterka,, M. Pexa, J. Čedík, D. Mader and M. Kotek
Comparison of exhaust emissions and fuel consumption of small combustion engine of portable generator operated on petrol and biobutanol
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Comparison of exhaust emissions and fuel consumption of small combustion engine of portable generator operated on petrol and biobutanol

B. Peterka¹,*, M. Pexa¹, J. Čedík¹, D. Mader¹ and M. Kotek²

¹ Czech University of Life Sciences Prague, Faculty of Engineering, Department for Quality and Dependability of Machines, Kamycka 129, CZ165 21 Prague 6, Czech Republic
² Czech University of Life Sciences Prague, Faculty of Engineering, Department of Vehicles and Ground Transport, Kamycka 129, CZ165 21 Prague 6, Czech Republic
*Correspondence: peterka@oikt.czu.cz

Abstract:

The paper is focused on the comparison of exhaust emissions and fuel consumption of small internal combustion engines operated on petrol and biobutanol. In case of this research, small engines are represented by combustion engine of portable power generator with nominal power of 4.8 kW equipped with carburettor for fuel mixture preparation. Exhaust emissions and fuel consumption were measured while gradual loading of the combustion engine. BrainBee emission analyser, Bruker FTIR spectrometer and EEPS particle analyser was used for the measurement. The mass fuel consumption was monitored using laboratory scale Vibra. The initial hypothesis expected that exhaust emissions and fuel consumption will be higher in case of use of nonstandard fuels. From the viewpoint of particles count can be stated, that their productions are at very low level for both kinds of used fuels. Production of carbon monoxide and hydrocarbons is higher than in case of usual automobile engine due to simple engine control system and absence of additional emission control device (catalytic converter). The fuel consumption increased while using n-butanol as a result of its lower calorific value.

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873–882 J. Pavlu, V. Jurca, Z. Ales and M. Pexa
Comparison of methods for fuel consumption measuring of vehicles
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Comparison of methods for fuel consumption measuring of vehicles

J. Pavlu*, V. Jurca, Z. Ales and M. Pexa

Czech University of Life Sciences Prague, Faculty of Engineering, Department for Quality and Dependability of Machines, Kamycka 129, 165 21 Prague 6, Czech Republic
*Correspondence: jindrichpavlu@seznam.cz

Abstract:

 Essential task for companies in these days is to reduce operating costs and optimization of workflow processes of machines, in order to increase the competitiveness and productivity. Telematics systems is relatively widespread and utilized for fleet management and enables collecting a wide range of operating parameters. One of the monitored parameters of operating costs is fuel consumption of machines. The collection of data on fuel consumption can be realized using various methods. By default, the fuel consumption data is transmitted from CAN–BUS which does not always coincide with the value of the real fuel consumption. Another possible way of fuel consumption monitoring is realized via installation of capacitance probe mounted directly into the fuel tank. The principle of measurement of these two methods is different, and each method has its own specifics. For instance, a capacitive probe enables detection of non-standard decreases of fuel level in the fuel tank. The aim of this paper is to compare the methods of fuel consumption measuring via the CAN–BUS and utilization of capacitive fuel probe. Measuring unit Gcom was used for collecting data which sends data of fuel consumption to the server in real–time. The purpose of this paper is to prove or disprove the hypothesis that measured fuel consumption is statistically significant between measuring via CAN-BUS compared to capacitance probe.

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540–546 M. Pexa, J. Čedík,, F. Kumhála and R. Pražan
Estimation of mulching energy intensity
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Estimation of mulching energy intensity

M. Pexa¹, J. Čedík,¹*, F. Kumhála² and R. Pražan³

¹Czech University of Life Sciences, Faculty of Engineering, Department for Quality and
Dependability of Machines, Kamycka 129, CZ 165 21 Prague 6, Czech Republic
²Czech University of Life Sciences, Faculty of Engineering, Department of Agricultural
Machines, Kamycka 129, CZ 165 21 Prague 6, Czech Republic
³Research Institute of Agricultural Engineering, p.r.i., Drnovská 507, CZ 161 01
Prague 6, Czech Republic
*Correspondence: cedikj@tf.czu.cz

Abstract:

Mulching is one of the energy-intensive activities in agriculture. The energy is gained from the consumed fuel. Besides the consumed fuel the combustion engine produces harmful and unharmful exhaust gases. The general trend is to reduce the production of harmful constituents of emissions as well as carbone dioxide. This can be achieved by various construction modifications or additional modifications of exhaust gases. It is possible to estimate the energy intensity in advance by several different ways. The paper presents the estimation based on measured complete characteristics of emissions production and the fuel consumption of used combustion engine and on the measured on-board data. The results show that the estimation of fuel consumption and thus also production of carbon dioxide can be relatively successful. The estimation differs quite significantly for other emissions components. During different transition modes of the combustion engine there is a change of emissions production which is hard to describe. The solution could lie in use of other parameters determining the operation mode of the engine in addition to the commonly used speed and torque of the combustion engine.

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167–173 B. Peterka, M. Pexa, J. Čedík and Z. Aleš
The influence of biobutanol on performance parameters of mobile generator
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The influence of biobutanol on performance parameters of mobile generator

B. Peterka, M. Pexa, J. Čedík* and Z. Aleš

Czech University of Life Sciences Prague, Faculty of Engineering, Department for
Quality and Dependability of Machines, Kamycka 129, CZ 165 21 Prague 6,
Czech Republic; *Correspondence: cedikj@tf.czu.cz

Abstract:

The expansion of biofuel also affects the area of using small internal combustion engines, which are widely used in municipal equipment such as minitractors,  chainsaws, mowers and brush cutters. These small engines have their specific  operation conditions, especially given by high operating speeds and high loads. Current legislation for fuel BA 95 prescribes the addition of ethanol. The percentage is however very small nearly not affecting the operation of combustion engines. The paper is focused on biobutanol since it is considered as more advanced type of alcohol based fuel than bioethanol. The measurement is focused on a small combustion engine of portable generator with maximum power of 2.5 kW. There is monitored influence of biobutanol on their performance parameters. As the mixing ratios are in the range of 100% fuel BA 95 (without ethanol) to 100% biobutanol.

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1332-1341 M. Kotek, P. Jindra and J. Mařík
Speed limits and their impact on emissions production and fuel consumption
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Speed limits and their impact on emissions production and fuel consumption

M. Kotek, P. Jindra* and J. Mařík

Czech University of Life Science Prague, Faculty of Engineering, Department of Vehicles and Ground Transport, Kamýcká 129, CZ16521 Prague, Czech republic
*Correspondence: jindrap@tf.czu.cz

Abstract:

The article deals with emissions and fuel consumption of road vehicles in real traffic conditions. The aim of this study was to prove or disprove correctness of the decision of Prague city government to change the speed limits from 70 km h-1 to 50 km h-1 on the parts of one main road leading to/from Prague. For measurements in real traffic conditions was used 2 typical Czech cars Skoda with manual transmission (Fabia 1.2 MPI with petrol engine and Octavia 2.0 TDI with diesel engine). Measurements were performed on both of directions on defined road segment.

At speed 50 km h-1 the measurement was repeated 5 times at 3rd and 5 times on 4th gear. Similarly at speed 70 km h-1 the measurement was repeated 5 times at the 4th and 5th gear. The aim was to operate the vehicle in the normal engine loads.
The results demonstrate the fundamental assumption that at the higher allowed vehicle speed the engine is more loaded and therefore produces a higher amount of emissions, but according to a higher vehicle speed the emissions are produced on the defined segment for the shorter time. A similar trend is evident even in fuel consumption. The results also indicate the depending on the power reserve of specific vehicle. When the vehicle is more powerful, higher permitted speed is preferable.

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541-549 J. Čedík,, M. Pexa, J. Mařík, V. Hönig, Š. Horníčková and K. Kubín
Influence of butanol and FAME blends on operational characteristics of compression ignition engine
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Influence of butanol and FAME blends on operational characteristics of compression ignition engine

J. Čedík¹,*, M. Pexa¹, J. Mařík¹, V. Hönig², Š. Horníčková² and K. Kubín³

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department for Quality and Dependability of Machines, Kamýcká 129, CZ16521 Prague 6, Czech Republic; *Correspondence cedikj@tf.czu.cz
²Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Department of Chemistry, Kamýcká 129, CZ16521 Prague 6, Czech Republic
³Research Institute of Agricultural Engineering, p.r.i., Drnovská 507, CZ16101 Prague 6, Czech Republic

Abstract:

The issue of the use of alternative fuels in diesel engines is discussed in this paper. The purpose is to reduce the dependence of EU Member States on fuels of petroleum origin. One of the possibilities is the use of butanol produced from organic products. The use of pure butanol in diesel engines is not possible. However, it may be used as an additive for fuels of petroleum origin or adding to oil for improving the operating conditions of the engine. Successively 10, 30 and 50% n-butanol was used as an additive. Turbocharged combustion engine of the tractor Zetor 8641 Foretrra was used to the test. This engine was burdened using a dynamometer to the PTO. Performance parameters and fuel consumption of the engine were monitored during measurements. Performance parameters of the engine decreases and fuel consumption increases due to the properties of butanol. Cleansing properties of butanol which restrict carbonization on functional surfaces of the engine seems advantageous.

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585-595 M. Lukeš, M. Kotek and M. Růžička
The energy consumption of public transit under rural and suburban conditions
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The energy consumption of public transit under rural and suburban conditions

M. Lukeš*, M. Kotek and M. Růžička

¹Czech University of Life Sciences Prague, Faculty of Engineering, Kamýcká 129, CZ16521 Prague, Czech Republic; *Correspondence: lukesm@tf.czu.cz

Abstract:

The aim of paper is to investigate an energy consumption of public transit focused on regular commuting from suburban locations. Surveyed suburban settlements have become a part of ‘urban sprawl’ process in the suburbanized hinterland of Prague’s city. The transport links are strongly influenced by the catchment area of Prague’s city that has a dominant position in surveyed region and the most of the existing transport links are carried out in relation to the Prague’s city on radially oriented roads. The traffic intensities are often on a roads’ full capacity during peak hours or the roads are even congested alongside a ride to the city. The 10 suburban settlements were selected for the purpose of the fuel consumption investigation. Authors have focused on the journeys carried out during the morning peak hours of the ordinary working days when the transport demands are saturated. The fuel consumption investigation has involved the journeys by public transit (commuter bus) and by passenger car. Obtained results have proved possibilities of significant fuel consumption savings under condition that the bus transit preference would be effectively used. The energy efficiency of bus public transit allows to achieve the similar energy consumption per passenger as an ordinary passenger car has at a low occupancy rate of bus.

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