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Method for Determining Volumetric Efficiency and Its Experimental Validation


Modern means of transport are basically powered by piston internal combustion engines. Increasingly rigorous demands are placed on IC engines in order to minimise the detrimental impact they have on the natural environment. That stimulates the development of research on piston internal combustion engines. The research involves experimental and theoretical investigations carried out using computer technologies. While being filled, the cylinder is considered to be an open thermodynamic system, in which non-stationary processes occur. To make calculations of thermodynamic parameters of the engine operating cycle, based on the comparison of cycles, it is necessary to know the mean constant value of cylinder pressure throughout this process. Because of the character of in-cylinder pressure pattern and difficulties in pressure experimental determination, in the present paper, a novel method for the determination of this quantity was presented. In the new approach, the iteration method was used. In the method developed for determining the volumetric efficiency, the following equations were employed: the law of conservation of the amount of substance, the first law of thermodynamics for open system, dependences for changes in the cylinder volume vs. the crankshaft rotation angle, and the state equation. The results of calculations performed with this method were validated by means of experimental investigations carried out for a selected engine at the engine test bench. A satisfactory congruence of computational and experimental results as regards determining the volumetric efficiency was obtained. The method for determining the volumetric efficiency presented in the paper can be used to investigate the processes taking place in the cylinder of an IC engine.

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Dry sliding wear behaviour of fly ash particles reinforced AA 2024 composites

.1016/0043-1648(95)06657-8 [5] Deuis R.L., Subramanina C., Yellup J.M., Compos Sci Technol., 57 (1997), 415. [6] Seah K.H.W., Hemanth J., Sharma S.C., Materials and Design, 24(2) (2003), 87. [7] Siddiquea R., Noumoweb A., Conservation and Recycling, 53 (2008), 27. [8] Belger M.A., Rohatgi P.K., Gupta N., TMS annual meeting, (2006), p. 95–204. [9

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Synthesis and characterization of Ag@polycarbazole nanoparticles using different oxidants and their dispersion behavior

considerably thicker, π−π* transition was also observed. Similarly, in this study, the dispersion behavior was found significantly increased when NPs were coated by PCz, however, the increase was connected with the increase in polymer thickness. It was more pronounced in case of FeCl 3 . Therefore, it was concluded that PCz which possess good optical and dispersion behavior could be tailored around Ag NPs in a composite form and a material ensuring conservation of existing properties along with combining of complementary characteristics. The study could be helpful to explore

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Synthesis and characterization of nanocrystalline barium strontium titanate powder by a modified sol-gel processing

/40) calcined at 750 °C for 2 h. As can be seen, the presence of Ba, Sr, Ti and O was detected in the spectra. The results confirm that pure BST is a dominant phase. Furthermore, the composition ratio (Ba/Sr) of the as prepared powder was confirmed using the microarea EDS analysis. Stoichio-metric ratios of the main metallic components of the BST60/40 ceramics are as follows (in mass %): Ba – 38.64 %, Sr – 16.43 %, Ti – 22.44 %. The results of the measurement, given in Fig. 6 , are in acceptable agreement with the stoichiometric ratios mentioned above. Thus, the conservation

Open access