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Merkisz J.,Poznan University of Technology | Lijewski P.,Poznan University of Technology | Fuc P.,Poznan University of Technology | Weymann S.,Industrial Institute of Agricultural Engineering
Eksploatacja i Niezawodnosc | Year: 2013

The paper discusses the issue of exhaust emissions from non-road vehicle engines. In the first part of the paper American regulations on the procedures of engine testing in operation were briefly characterized. The said regulations are a novel solution and were introduced as one of the first of this type worldwide. In the next part of the paper the authors presented the results of the exhaust emission tests from a farm tractor performed under actual operating conditions during fieldwork. For this purpose PEMS (Portable Emissions Measurement System) was used. The tests were carried out for different test procedures such as the NTE (Not- To-Exceed) procedure. The analysis of the test results was performed chiefly in the aspect of the NTE test applicable in the U.S. The analysis pertains chiefly to the engine operating conditions and exhaust emissions. European legislation currently does not require such tests and that is why the presented tests are related to the American procedures. The performed tests and their analysis led to a formulation of conclusions related to the engine operating conditions and its exhaust emissions. Source

Ptaszek P.,Agricultural University of Krakow | Kabzinski M.,Agricultural University of Krakow | Ptaszek A.,Agricultural University of Krakow | Kaczmarczyk K.,Agricultural University of Krakow | And 2 more authors.
Food Hydrocolloids | Year: 2016

This research study analysed the rheological properties of fresh food foams based on egg white protein, and with the addition of apple pectins and xan than gum. The rheological analysis was carried out using the large amplitude oscillatory shear (LAOS) technique. From the obtained results two types of Lissajous figures were constructed, describing the elastic and viscous properties. The obtained figures were subjected to geometrical decomposition, which resulted in the determination of the stress values characteristic of nonlinear purely elastic and purely viscous properties. The Fast Chebyshevs Transform allowed for the calculation of the Chebyshev coefficients, and further detailed analysis of rheological behaviour of foams as a function of strain amplitude. The determination of the values of elastic and viscous Chebyshev coefficients allowed for the interpretation, with high resolution, of nonlinear rheological properties of the obtained foams. © 2015 Elsevier Ltd. Source

Merkisz J.,Poznan University of Technology | Lijewski P.,Poznan University of Technology | Fuc P.,Poznan University of Technology | Siedlecki M.,Poznan University of Technology | Weymann S.,Industrial Institute of Agricultural Engineering
Applied Engineering in Agriculture | Year: 2015

This article presents investigations of fuel consumption and CO2 emission of a farm tractor operating with a cultivator. The cultivator has been designed to operate at greater speeds of up to 15 km/h. During the tests, the tractor operated with different speeds, which influenced the fuel consumption and the time of operation. An increase in the cruising speed resulted in greater fuel consumption and a reduced time of operation. A fuel consumption curve was determined depending on the tractor speed. At the same time, the authors assessed the quality of the cultivation through soil analysis after the cultivation. The fuel consumption was measured with the carbon balance method - the most accurate method available. Such measurements were performed by the Portable Emission Measurement System (PEMS) equipment. The investigations utilizing the PEMS equipment enable measurements of the exhaust emissions under actual operating conditions, during fieldwork. The methodology used in the research is the most accurate and most reliable one currently available. It takes into account all of the variables of actual operation. This method is a state-of-The-Art achievement in exhaust emissions measurement and has great potential. It may be successfully used for research related to assessment of energy consumption of farm tractors depending on the analyzed factors, e.g.Type of soil, design of tools, and method of fieldwork. The performed tests allowed formulating conclusions related to the influence of the speed of the farm tractor with the cultivator on fuel consumption and emission of CO2. From the test, it follows that upon reaching a certain operating speed the increment of the fuel consumption is getting smaller while the time efficiency increases. The authors also observed that the above did not have impact on the quality of the cultivation. The presented results of the investigations and their analysis confirm the usefulness of the applied methodology in the assessment of energy consumption of farm tractors and machines during fieldwork operation. © 2015 American Society of Agricultural and Biological Engineers. Source

Bartkowski D.,Poznan University of Technology | Mlynarczak A.,Poznan University of Technology | Piasecki A.,Poznan University of Technology | Dudziak B.,Industrial Institute of Agricultural Engineering | And 2 more authors.
Optics and Laser Technology | Year: 2015

The paper presents the method of preparation and study results of metal matrix composite coatings (MMC coating) in the system of Stellite-6 and tungsten carbides. Changes in microstructure, corrosion resistance, microhardness, phase and chemical composition as well as surface conditions were investigated. Stellite-6/WC MMC coatings were prepared by laser cladding technology using a 1 kW continuous wave Yb:YAG disk laser with a powder feeding system. Two different powder mixtures containing 30% and 60% of WC and three different values of laser beam power were used. It was found that increasing WC values caused an increase in microhardness on the cross-section of the produced coating in comparison to the substrate. Depending on the laser beam power, the coatings produced with 30% WC achieved microhardness in the range from about 350 HV0.05 (700 W) to about 680 HV0.05 (550 W). Twice as large amount of WC particles in the powder mixture resulted in increase of microhardness from about 700 HV0.05 (700 W) to about 1500 HV0.05 (550 W). In the coating M7C3, M6C and M23C6 carbides were identified by an X-ray diffraction method. Special attention was given to bondings between carbide particles and metal matrix, which had a characteristic microstructure. A reduction of corrosion resistance with increasing WC content in coating was also discovered. © 2014 Elsevier Ltd. All rights reserved. Source

Szczepaniak J.,Industrial Institute of Agricultural Engineering | Tanas W.,Lublin University of Life Sciences | Kromulski J.,Industrial Institute of Agricultural Engineering
Annals of Agricultural and Environmental Medicine | Year: 2014

Many people are exposed to whole-body vibration (WBV) in their occupational lives, especially drivers of vehicles such as tractor and trucks. The main categories of effects from WBV are perception degraded comfort interference with activitiesimpaired health and occurrence of motion sickness. Absorbed power is defined as the power dissipated in a mechanical system as a result of an applied force. The vibration-induced injuries or disorders in a substructure of the human system are primarily associated with the vibration power absorption distributed in that substructure. The vibration power absorbed by the exposed body is a measure that combines both the vibration hazard and the biodynamic response of the body. The article presents measurement method for determining vibration power dissipated in the human whole body system called Vibration Energy Absorption (VEA). The vibration power is calculated from the real part of the force-velocity cross-spectrum.The absorbed power in the frequency domain can be obtained from the cross-spectrum of the force and velocity. In the context of the vibration energy transferred to a seated human body, the real component reflects the energy dissipated in the biological structure per unit of time, whereas the imaginary component reflects the energy stored/released by the system. The seated human is modeled as a series/parallel 4-DOF dynamic models. After introduction of the excitation, the response in particular segments of the model can be analyzed. As an example, the vibration power dissipated in an operator has been determined as a function of the agricultural combination operating speed 1.39 4.16 ms-1. Source

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