Wyniki wyszukiwania - BazTech

1

Analiza drgań tłokowego silnika lotniczego

Skiba K., Wendeker M., Czarnigowski J., Ferdynus M., Sokołowski P.

Logistyka

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2014

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nr 6

9591--9598

PL

W artykule opisano analizę drgań lotniczego silnika tłokowego ASz-62IR-16E. Wyniki opracowano na podstawie spektrum drgań jednostki napędowe, oraz wartości skutecznych przyspieszeń drgań RMS dla określonych prędkości obrotowych. Przedstawiono sposób identyfikacji częstotliwości szczytowych wartości amplitud dla widma drgań. Omówiono również zależność prędkości obrotowych jednostki napędowej na drgania generowane przez silnik. Ustalono zakres prędkości obrotowych mających wpływ na powstawanie okresowych wymuszeń.

EN

The article describes the vibration analysis of aviation piston engine ASz-62IR-16E. The results are based on the vibration spectrum of the engines, and the effective RMS accelerations for specific speeds. The paper presents a method of identifying the frequency of peak amplitudes of vibration spectra. It also discusses the dependence of rotational speed of the drive unit to the vibrations generated by the engine. Established speed range having an impact on the formation of periodic excitations.

2

DFT Calculations of the Structure and Adsorption of HCO3 - Species on the Surface of Al2O3 Catalyst

Gao H. W., Guo L., Yan T. X.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 12

2119-2127

EN

Density functional theory (DFT) calculations have been carried out to study the structure and adsorption of HCO3 - species on Al2O3 catalyst using MPW1PW91 function and the different basis sets of 6-31G, 6-311G, 6-311+G(d), DGDZVP, DGDZVP2, PVQZ, SDD, LANL2DZ, LANL2MB. The geometrical structures and vibration spectra were obtained with DFT methods and compared with the corresponding experimental values. Theoretical calculations show that the calculated IR spectra using MPW1PW91/6-311G, MPW1PW91/SDD and MPW1PW91/LANL2DZ methods are in good agreement with the experimental spectroscopic results.

3

Diagnostics of steam turbine fluid-flow systems on the basis of vibration spectra

Gałka T.

Systems : journal of transdisciplinary systems science

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2004

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Vol. 9, Sp. 2/1

77-85

EN

Introduction of Condition-Based Maintenance (CBM) in scheduling turbine overhauls imposes new demands on technical condition assessment procedures. Fluid-flow system condition assessment is of particular importance, as this system has substantial contribution into total forced outage time. Vibration characteristics pro-vide an important tool for this purpose. Certain components of vibration spectra contain information on technical condition of individual stages and elements. With a purpose-developed model, condition assessment can be accomplished without turbine disassembly. Statistics and trend analysis are of particular suitability. The following paper present theoretical background and model, as well as a description of several case studies for turbines in Polish utility power plants. Certain failures, detected with vibration-based methods, have been presented and possibilities of wider applications have been outlined.