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Abstract

The paper presents results of experimental studies concerning CO2 emission of S-4003 diesel engine Ursus C-360 at a variable fuel injection advance angle and opening pressure of injectors. Measurements were made on the dynamometric stand on the test bench. The engine operated according to the load characteristic at two characteristic rotational speeds i.e., at the maximum torque velocity (1600 rpm) and at the rated speed (2200 rpm). In each measurement point of load characteristics, CO2 concentration was measured in exhaust gases with the use of exhaust gases analyser M-488 Multigas Plus. For a more detailed analysis of the CO2 content in exhaust gases, additional change of O2 level emission was presented, which in the biggest amount combines elementary carbon included in fuel during combustion. The studies showed the CO2 content reduction in exhaust gases at the reduced (by 3º of crankshaft rotations) fuel injection advance angle in comparison to the nominal angle by 4.5% at the rotational speed of 1600 rpm and by 5.7% at the speed of 2200 rpm (the average values for all measurement points of load - brake horsepower of engine). Similarly, CO2 concentration decrease in exhaust gases of the investigated engine was reported for the increased (by 1.5 MPa) opening pressure of injectors in comparison to the nominal pressure, on average by 9.8% for the speed of the maximum rotational moment and by 4.5% for the rated speed.

Abstract

The introduction of solutions conventionally called Industry 4.0 to the industry resulted in the need to make many changes in the traditional procedures of industrial data analysis based on the DOE (Design of Experiments) methodology. The increase in the number of controlled and observed factors considered, the intensity of the data stream and the size of the analyzed datasets revealed the shortcomings of the existing procedures. Modifying procedures by adapting Big Data solutions and data-driven methods is becoming an increasingly pressing need. The article presents the current methods of DOE, considers the existing problems caused by the introduction of mass automation and data integration under Industry 4.0, and indicates the most promising areas in which to look for possible problem solutions.

Abstract

This work deals with the study of polymers, and, in particular, polyethylene; its production, types, properties, and usage. The experimental part evaluates the changes of properties of the polyethylene film to be reused under various exposure conditions and selection of the most suitable medium for its application. The film made of low-density polyethylene (LD-PE) was influenced by aggressive media with different pH, specifically Savo for the disinfection, Savo as a Saponate for dish washing and Coca-Cola. On LD-PE films the water absorption and melting temperature evaluation tests were performed. Carried out tests show that the most aggressive medium for LD-PE film from used media is Coca-Cola. The most effective application of LD-PE film like wrapping on container transported is the Savo used as a Saponate for dish washing.

Abstract

An evaporative cooling system was designed and constructed to increase the shelf life of stored vegetables. The evaporative cooler was tested and evaluated using freshly harvested roma tomatoes. The equipment operates on the principle of evaporative cooling which increased the relative humidity and decreased temperature in the preservation chamber. The storage system was made up of wood of 25.4 mm thickness. A side of the system is made of jute sack, which was moistened with water flowing through a series of perforated pipes from a reservoir located at the top of the storage system. The water flowed under gravity. The relative humidity and temperature of the tomatoes were analyzed using tinytag humidity, temperature data logger. The weight loss of the tomatoes was also analyzed using a dial gauge scale. The results revealed that there was significant difference in using the evaporative cooling system for storing tomatoes as compared to ambient conditions. The average cooling efficiency was found to be 81%. The average temperature achieved in the cooling system dropped to an average of 23℃ when compared to the average ambient temperature of 33℃, and the relative humidity also increased up to 99% when compared to the average ambient of 59%. The analysis of the evaporative cooling system showed that tomatoes can be stored for more than 6 days with negligible changes in weight, colour and firmness as compared to those under ambient condition, which deteriorated after day 3. The evaporative cooling system was found to be effective and hence can be used by farmers, households, and tomato processing factories for short term storage of fresh tomatoes.

Abstract

Every year approximately 70 million passenger cars are being produced and automotive industry is much bigger then just passenger cars. The impact of automotive industry on the environment is tremendous. From extracting raw materials through manufacturing and assembly processes, exploitation of the vehicle to the reprocessing irreversible, extensive environmental damage is done. The goal of this study is to show how implementing eco-design processes into supply chain management can reduce the impact of automotive industry on the environment by e.g. reducing the use of the fuel, increasing the use of recycled materials. Focus is on evaluation of current state, environmental impacts and potential improvements for design, raw materials, manufacturing and distribution and end-of-life phase.

Abstract

The aim of the study was to conduct an economic analysis of the possibilities of using photovoltaic (PV) installations in selected farms. Two selected online PV calculators were used for the analysis. The research included 15 farms located in the Małopolskie Province. For a PV installation estimated using Calculator 1, Hewalex, the payback period ranged from 5.5 to 7 years for the 40% subsidy option and from 9 to 11 years without the subsidy, respectively. On the other hand, the payback period estimated with the use of the SmartekDom calculator ranged from 6 to 8 years for the option with 40% subsidy. However, without the subsidy, the period ranged from 7 to even 13 years.

Abstract

Modern methods of testing materials require the use of the latest technologies and combining measurement and calculation methods. It is important to find a quantitative way of describing, among other things, the failures so that it can help to design with high accuracy. This paper studies loading orientations on crack shape and fracture surface changes. The advantage of the entire fracture surface method is simplicity and applicability in studies on other materials, shapes and loadings. A higher values of fracture surface parameters (Sx, Vx) was observed in failure specimens with lower σ/τ (B/T) ratios. It has been observed that largest crack lengths with a small number of cycles occur for loading combinations different then B=T. As well as analyzed surface parameters Sx, Vx, are higher for larger number of cycles to crack initiation (Ni) values.

Abstract

In the aspect of the course and analysis of products of biomass fuels combustion in grill feed boilers, the combustion process of wheat straw and meadow hay were assessed taking into consideration conditions of SO2 emission. Different types of briquettes used in the research not only had various chemical properties but also physical properties. In the aspect of assessment of energy and organic parameters of the combustion process, the sulphur content in biomass becomes a significant factor at its energy use. Registered emission during combustion of meadow hay biomass referred to wheat biomass was for A and B type briquettes correspondingly higher by ca. 320 and 120%. Differences in SO2 emission at combustion of various biofuel forms in the aspect of the relation with the remaining combustion parameters including mainly with air flow require, however, further research that leads to development of low-emission and high-efficient biofuel combustion technologies in low-power heating devices.

Abstract

The axial crushing behaviour of tubes of different section shapes has been extensively investigated as they have an excellent energy absorption, but the thin walled corrugated tube structures have been designed to further improve their energy absorption performance. The study aims to analyze the effect of sinusoidal corrugations along cross section of the tube on peak force, energy absorption and specific energy absorption. In the present work the response surface methodology (RSM) using central composite design (CCD) has been used and simulation work is performed by using ANSYS workbench to explore the effects of geometrical parameters on the responses of constructing models.