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The present paper deals with the evaluation of the impact of newly developed biofuels together with a comparison with conventionally produced fuel, diesel, in terms of their impact on the technical and emission condition of a studied vehicle. The main energy and emission parameters of the internal combustion diesel engine were evaluated. For laboratory experiments, a discrete test method was used for comprehensive assessment, the procedure of which is described in the methodology of the paper together with a description of the measurement chain designed to achieve the determined results. The paper deals with the evaluation of the measured results of power, torque, consumption, and emissions such as CO2 and absorption coefficient. Among the technical parameters, the power and torque drop were observed for each biofuel. The decrease is attributed to lower values of calorific value, viscosity, and density. A positive effect was observed for the CO2 and absorption coefficient emission parameters, i.e., a decrease for each of the newly developed biofuels studied.

This article deals with the testing of regulating and non-regulating hydraulic pumps in laboratory conditions. The laboratory test was carried out on the hydraulic device consisting of two separate hydraulic circuits (for testing the non-regulating hydraulic pump and regulating hydraulic pump). A throttle valve or proportional throttle valve is used for loading. During the laboratory tests, the flow efficiency of the non-regulating hydraulic pump at rotation speed n = 1,500 rpm (nominal speed) was ηpp = 98.91% (0 MPa) and ηpp = 94.97% (20 MPa), and for the regulating hydraulic pump, the values were ηpp = 97.57% (0 MPa) and ηpp = 94.54% (20 MPa). The determined values of flow efficiency of hydraulic pumps determine the correct operation of the experimental hydraulic laboratory equipment.

The use of environmentally friendly hydraulic fluids is frequently influenced by the temperature reached in the hydraulic circuit. This paper presents an analysis of the effect of temperature on the lifetime of the hydraulic fluid and the hydraulic pump. The test was carried out by continuous loading with a pressure of 21 MPa and a temperature of 96 °C for 100 h. A pressure valve was used for the continuous loading and the temperature was maintained using a cooler. At intervals of 25 h, the flow characteristics of the hydraulic pump were measured and oil sampling was carried out. Subsequently, a comprehensive chemical and physical analysis was carried out. In the present paper, a comprehensive analysis of the influence of eco-friendly hydraulic fluid on the operation of a gear hydraulic pump has been carried out. The study itself did not show the negative influence of the eco-friendly hydraulic fluid on the operation of the gear hydraulic pump. It can be expected that the results of the study will enable the use of eco-friendly hydraulic fluids in environmentally sensitive areas. [ABSTRACT FROM AUTHOR]

Goal of this study was to investigate and evaluate an impact of two alternative fuels on smoke emissions in comparison to diesel fuel. This study observes three different combustion engine fuels: biodiesel produced by Meroco, Inc. Company (Alternative fuel I); biodiesel produced in factory situated in Sereď (Alternative fuel II); and conventional diesel fuel (Diesel fuel) from Slovnaft, Inc. Company service station. All measurements were repeated three times. Measurements were conducted by free acceleration test at different engine loads. A statistically significant difference (P 0.05). Tested engine has met the requirements of the EURO 3 emission limit values in relation to the measurement results of particulate matter emissions.

Paper presented is focused on the operating measurements of a tractor wet disc brake system. Operating measurements were evaluated after tractor’s operation at 500 Mth on the 3rd, 4th and 5th gear. Reference fluid and ecological fluid were tested during operation. In addition, work results include the evaluation of the fluid samples taken during the operational tests to monitor the tractor braking performance with wet disc brakes. Fluid samples were also tested in order to determine the changes in their physico-chemical properties. Chemical analysis was performed for both oil samples by means of X-ray fluorescence analysis according to the DIN 51829 and DIN 51399-2. Observed physical properties of the tested oils – density, viscosity, acid number, water content – were within the appropriate ranges after the end of test. Further analysis was focused on an amount of abrasive metals, contaminants, additives, and other important elements. On the basis of analyses conducted, it can be concluded that majority of elements preserved their original level showed at the 0 reference hour sample. In terms of the abrasion metals, an increase in their presence was not found. Furthermore, analysis of the physical properties of tested fluids did not prove their negative impact on the tractor wet disc brake system. Results of the operating measurements suggest that neither the applied conference fluid nor the ecological fluid showed negative effect on the minimum braking value. The minimum braking deceleration was implemented in accordance with the Law no. 106/2018.

This paper is focused on the impacts of the biodegradable hydraulic and transmission fluid (Universal Tractor Transmission Oil) on operation of tractor hydraulic and transmission systems. The fluid was used in the hydraulic and transmission systems of a Zetor Proxima 6321 tractor. Fluid samples were taken from the Zetor Proxima 6321 tractor at intervals of 250 engine hours. These samples were subjected to an infrared spectroscopy analysis in order to measure the total acid number and perform the ferrography analysis. This paper proves minimal impacts of the biodegradable hydraulic fluid on operation of the Zetor Proxima 6321 tractor. The biodegradable fluid meets the requirements for the operation of agricultural tractors in terms of low impacts on the wear of hydraulic components.

The main aim of the article is to present the design of laboratory test equipment, which is appropriate for monitoring the efficiency of oil filters and the system for evaluating the technical life of engine oils in terms of possible extension of service intervals. The functionality of the designed laboratory test equipment for the filtration of motor oils was verified by a practical experiment with a verification measurement and assessment of the suitability of the hydraulic circuit elements and the designed sensing equipment. The laboratory equipment enables the testing of oil filters with different filtration capacity during simultaneous testing in two separate hydraulic circuits with differently contaminated engine oil, while it enables laboratory measurements to be performed while simulating operating conditions.

The results of the work include research on changes in flow characteristics of gear hydraulic pump QHD 17 by simulating operating conditions on laboratory test equipment with assessment of influence of transmission-hydraulic fluid MOL Farm NH Ultra on technical and operational properties of hydraulic pump QHD 17. The laboratory test equipment makes it possible to repeatedly simulate real conditions under which the hydraulic system of the agricultural tractor operates, or to simulate the load with maximum pressure. By monitoring the change in the flow of the hydraulic pump at precisely determined intervals, which were 0 and 125 hours worked, the influence of the physical properties of the working fluid on the flow properties of the hydraulic pump was assessed and the measured data set was evaluated by mathematical-statistical analysis. Based on the physical properties of the tested MOL Farm NH Ultra fluid, which were determined from the samples taken at precisely determined intervals, no negative effect of the fluid itself as well as its properties on the flow efficiency of hydraulic pump QHD 17 was found.

The main goal of the presented paper was to design the measuring device of the external hydraulic circuit of the agricultural tractor, with the implementation of verification measurement and functionality of the device. At the same time, based on the device itself, which was verified in practice, a simulation was created in the FluidSim simulation program using the results of operational verification measurements. At the beginning of the structural design, the requirements for the electro-mechanical device were determined. This device is used for loading of the external hydraulic circuit, determination of the measuring object and flow calculation of the hydraulic pump. The verification measurement itself takes place at rated speed, constant and overpressure pressure in the tractor´s hydraulic system.

This paper focuses on the observation of a decrease in smoke opacity values in application of tested substance in selected vehicles with a compression ignition engine. The aim of the paper is to evaluate the ability of the tested substance to decrease the smoke opacity value in vehicles equipped with the compression ignition engine with mileage above 30,000 km. Measurements were carried out on the basis of determined measurement methods. From the results obtained in measurements on two vehicles, it can be concluded that the utilization of the tested substance led to a decrease in the smoke opacity value in both observed vehicles. The results of the experiment show further possibility for decreasing of emission production in exhaust gases of motor vehicles equipped with the compression ignition engine.

The purpose of this study was to investigate the effectiveness of feed mixtures with varying proportions of rape cakes to the weight of table eggs, its components, thickness and strength of egg shell. The eggs were from the final laying hybrid ISA Brown reared in the enriched cage system under experimental conditions. An age of laying hens was from 48 to 54 weeks. Egg weight and its components were measured on scales type KERN 440-35N, with an accuracy of 0.01 g and a maximum weight of 400 g. Egg white weight was calculated. The thickness and strength of the egg shell were measured from the dried samples at 55 °C. From each egg shell were cut 3 pcs of samples in the equatorial plane, one sample from the blunt end and one sample from the sharp end. Egg shell thickness was measured by test instrument SOME, type 60/0.01mm with a range of 0 - 10 mm. Egg shell strength was measured according to test instrument Instron with the small body, having a diameter 4.48 mm to exert pressure on the egg shell. The obtained data were assessed in the program system SAS, version 8.2. Based on the results observed in egg weight of our experiment we can conclude that in the group with share 5% of rape cakes was non-statistically significant (p >0.05) decreased egg weight compared to the control group. Egg weight was reduced in the group with share 10% of rape cakes, which confirmed a statistically significant difference compared to egg weight of control group (p <0.05). The differences among experimental groups with share 5% and 10% of rape cakes in feed mixture and as well as to control group were not statistically significant (p >0.05) in weight of egg yolk, egg white, egg shell and egg shell strength. Egg shell thickness was no statistically significant (p >0.05) increased in experimental group with share 5% of rape cakes and decreased in experimental group with share 10% of rape cakes versus control group. Increase of egg shell thickness in experimental group with share 5% of rape cakes versus decrease in experimental group with share 10% of rape cakes was statistically significant (p <0.05). [ABSTRACT FROM AUTHOR]

The aim of our study was to monitor the alterations of the on-board diagnostics (OBD) system of compressionignition combustion engines, when alternative fuels were used as a source of energy. We described a theory of emissions formation, diagnostics of standards defects of diesel engines and the formation of opacity. We also focused on processing and evaluation of readiness code, which is used to control various functions of the engine. Diesel fuel and alternative fuel were used for realized measurements in accordance with selected methodology. By means of measurements, we detected conditions of readinesscode and the coefficient values of light absorption factors of exhaust gases. Compared to the reference fuel, we detected no alterations in readinesscode, when we monitored the impact of fuel on the on-board diagnostics system. The components controlled by on-board diagnostics system (complex components, fuel system, exhaust gas recirculation) operate with the alternative fuel without detected defects of conditions. [ABSTRACT FROM AUTHOR]

The most accepted definition of biodiesel is stated at the EU technical regulation EN 14214 or in the USA in ASTM 6751-02. Because of this highly strict description only methyl esters of fatty acids conform to these definitions, nevertheless the term ''biodiesel'' is spread out to other alkyl fatty esters. Some countries have adopted bioethanol for replacement of methanol in biodiesel transesterification and thus assuring a full biological fuel. Of course, such position brings some problems in fulfilling technical requirements of EN 14214 or ASTM 6751-02. Biodiesel is actually a less complex mixture than petrodiesel, but different feedstock origins and the effect of seasonality may impose difficulties in fuel quality control. Since biodiesel is an alternative diesel fuel derived from the transesterification of triacylglycerol comprised materials, such as vegetable oils or animal fats, with simple alcohols to furnish the corresponding mono-alkyl esters, its composition depends on the raw material used, the cultivated area location, and harvest time. The choice of the raw material is usually the most important factor for fluctuations of biodiesel composition, because different vegetable oils and animal fats may contain different types of fatty acids. Important properties of this fuel vary significantly with the composition of the mixture. Cetane number, melting point, degree of saturation, density, cloud point, pour point, viscosity, and nitrogen oxides exhaust emission (NOx), for instance, deserve to be mentioned. One of the most important fuel quality indicators is the cetane number; however, its experimental determination may be an expensive and lengthy task. To weaken situation concerning biodiesel, the availability of data in the literature is also scarce. In such scenario, the use of reliable models to predict the cetane number or any other essential characteristic may be of great utility. We reviewed available literature to describe model, which will correlate cetane number of single mono-alkyl esters of fatty acids and their mixtures (biodiesels) with structural characteristics achieved by hydrogen nuclear magnetic resonance spectra. We suggest that this could be done through the application of a three stages process, combining statistical tools, fuzzy logic and artificial neural networks. Both treatments pointed to two major characteristics as determinants for the cetane number values: the number of carbon-carbon double bonds and the structure of alcohol moiety in each fatty ester. Neural Networks predicted cetane number quantitatively. The results are beneficial for the further development of analytical models addressing the quality of biofuels. [ABSTRACT FROM AUTHOR]

The technical and environmental parameters of the diesel internal combustion engine using two new samples of biofuels SAMPLE 1 and SAMPLE 2 were evaluated in this paper. SAMPLE 1 and SAMPLE 2 biofuels were tested on a LOMBARDINI LDW 502 internal combustion engine, which was loaded on a dynamometer according to the applicable national and international standards. This method can also be applied to marine engines and contribute to a higher level of marine ecology. The result of the testing was to determine the impact of tested biofuels on the technical parameters engine power and torque and the environmental parameters emissions of smoke, nitrogen oxides, and economy of the internal combustion engine-specific fuel consumption. From the measured data, another parameter was calculated, such as the injected fuel dose and the overall efficiency of the internal combustion engine. The results show that the new samples of SAMPLE 1 and SAMPLE 2 biofuels tested could be a suitable alternative to standard diesel. [ABSTRACT FROM AUTHOR]