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Numeryczna identyfikacja wpływu podłoża odkształcalnego na proces sprzężenia pomiędzy kołem napędowym a gąsienicą elastomerową

Czabanowski R.

TTS Technika Transportu Szynowego

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2012

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R. 19, nr 9

1889--1898, CD

PL

W artykule dokonano analizy oddziaływania podłoża odkształcalnego na wielkość przenoszonego momentu napędowego pomiędzy kołem napędowym a gąsienicą elastomerową. Wykazano, że oddziaływanie podłoża odkształcalnego, wskutek dodatkowych nacisków na łuku opasania koła napędowego może, w pewnych warunkach, znacząco zwiększać moment przenoszony przez sprzężenie cierne koła napędowego z gąsienicą elastomerową. W analizie uwzględniono ograniczoną przydatność modelu Eulera do opisu przenoszenia momentu pomiędzy kołem napędowym z podatną okładziną elastomerową a gąsienicą elastomerową.

EN

The article includes the analysis of deformable ground influence on the volume of driving moment transmitted between a drive pulley and elastomeric track. It has been demonstrated that the influence of deformable ground, as a result of additional pressures working on wrap of a drive pulley may, in some circumstances, considerably increase the moment transmitted by means of friction feedback of a drive pulley with elastomeric track. Increase of driving moment may be higher than 50%. The analysis includes limited applicability of Euler and Entelwein’s law in the description of transmitting the moment between a drive pulley with elastomeric lining and elastomeric track.

2

Modelowanie samochodowej przekładni cięgnowej

Bieniek A., Jantos J.

Czasopismo Techniczne. Mechanika

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2004

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R. 101, z. 7-M/1

95--104

PL

W opracowaniu sformułowano opis matematyczny bezstopniowej przekładni cięgnowej. Przyjęto Coulombowski model tarcia, a problem współpracy cięgna z kołem opisano modelem Eulera. Wykorzystując przybliżone zależności geometryczne, wprowadzono wzory na wymaganą wartość siły naporu w kołach przekładni. Określono również w sposób analityczny wymaganą wartość siły naporu w zależności od przełożenia przekładni i doprowadzonego momentu obrotowego. Wyniki obliczeń porównano z wynikami pomiarów. Opracowany model może być wykorzystany w badaniach symulacyjnych i w procesie sterowania przekładnią.

EN

In this paper the mathematical model of continuously variable transmission has been formulated. The Coulomb friction model has been assumed and the cooperation among the band and the wheels with the Euler model has been described. Using the approximate geometrical relations, the formulas for demanded thrust force have been derived. Also on the analytical way the thrust ratio as a function of transmission ratio and input torque has been determined. The computing results have been compared with the experimental results. The proposed model may be used in simulation investigations and in the control process.

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Application of the coupled Euler / flight dynamics model into analysisof a rapid pull-up manoeuvre

Goraj Z., Iglewski T.

Research Bulletin / Warsaw University of Technology, Institute of Aeronautics and Applied Mechanics

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2000

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nr 10

113-120

EN

The Eater flow model for in viscid, compressible gas and the aircraft flight dynamics model were coupled to analyse rapid pull-up manoeuvre. The Euler flow equations were used to obtain aerodynamic forces and moments acting on a simplified aircraft configuration, considered as a rigid body. The McCormack predictor-corrector scheme for a finite differences representation was used as a numerical method for solving the Euler flow equations. The second order artificial viscosity was introduced to improve convergence of the scheme. Far field boundary conditions in the Euler model were determined from the steady state conditions of in the horizontal flight. Aircraft components in the body frame of were computed having known the of attack of the aircraft and its speed. The air density and pressure correspond to the height. From the boundary condition on the wing surface it follows that local flow vector is tangent to the local surface. 225200 grid points in five connected structural grid blocks in computations. The flight dynamics equations of motion were used to describe the aiecraft dynamics. No additional aerodynamic derivatives were considered. Some dynamic phenomena and damping effects (including hysteresis) were taken into account. In the simulation process both models were used and coupled by means of the mutual data transfer process. Any change of flight conditions immediately influences on the flow. Initial conditions for the flight dynamics equations of motion were settled up coming from the solutionof the Euler flow model for several cases of stationary flow. Only symmetrical motion and symmetrical airflow were examined. This makes it possible to use a grid for half of the aircraft only. The influence of the horizontal tailplane and fuselage on the main wing flow was neglected. The results of simulation (including flight path history, surface loading, aerodynamic forces and moments) were compared to those of classical approach, obtained from pure flight dynamics equations of motion.