The tests have been carried out on granulation of fly ash that may significantly reduce the consequences of its storage and transport harmful to the environment, mainly secondary dusting. Granulation was conducted using a disk granulator. The experiments involved the evaluation of a loose additive (bentonite) impact, the analysis of moisture content and water and sodium glass impact, the optimisation of the added bentonite amount and the granulated product breaking resistance test. The were examined such parameters as the ratio of ash to fillers, the amount of supplied binding liquid (distilled water or waterglass) and the place of its feeding. The addition of bentonite to bed (ash) made it possible to completely granulate the material. The introduction of waterglass in place of demineralised water produced the desired effect.

Oil-coolers are necessary components in high performance diesel engines. The heat removed by the cooler is a component in the total heat rejection via the engine coolant. Oil-cooler absorbs the heat rejected during the piston cooling and engine rubbing friction power loss. During flows of both coolant and engine oil via the oil-cooler, some flow resistances occur. The aim of the study is to determine values of the flow resistance coefficient for oil going through the cooler at various temperatures. The test stand was developed to determine time needed to empty tanks from liquids flowing through oil-cooler. The flow model was elaborated to study the mentioned flow resistance coefficient with respect to changing liquid temperature. The 20 °C increase in liquid temperature resulted in a flow resistance coefficient decrease of 30% for coolant and of the much more for engine oil. It was found that better results would be achieved with flows forced by means of pumps instead of using gravitational forces on the test stand.

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Abstract. The article primarily presents a schematic idea of the operation of innovative ventilation shapes with adjustable performance. Then, it was pre-verified by measuring static pressure on the walls of ordinary fittings and innovative T-type fittings. The presented fittings have features that allow for very precise control of the performance of ventilation streams in various configurations. The most important diagrams in the article show that there are simple methods for distributing air streams, even in mutually perpendicular channels leading to minimized flow losses. The presented results of comparative tests carried out on ordinary and innovative T-shaped fittings show very favorable tendencies which are characterized by a several-dozen-percent drop in pressure in similar measurement ranges.

The frictional issues during motion of the axis-wheels assembly occurring in contact wheel–rail and in bogie bearing were studied. The influence of greases upon friction therein was also considered. The lateral dynamic behavior of the four-axle freight wagon model with two-axle Y25 bogies equipped with swing bolster was analyzed. Simulation models of such a wagon with bogies with and without swing bolsters were elaborated for calculations considering the nonlinearities of wheel–rail contact geometry and nonlinear methods of bogie stability. In these two options, the cases of empty and fully loaded wagon bodies were considered. The lateral dynamic models with 22 and 24 degrees of freedom were considered to determine the nonlinear critical speeds of a freight wagon. It was found that the resistive torque in bearings of the assembly studied varied nonlinearly with wagon speed. During motion along the curve track, values of such a torque can be higher by 50% in case of the wheel under overloading and lower by 50% in case of the wheel under underloading, respectively, compared to those obtained during motion along straight track.