Wyniki wyszukiwania - BazTech

Ograniczanie wyników

3 Applied Mechanics and Engineering

Powiadomienia systemowe

Sesja wygasła!
Sesja wygasła!
Sesja wygasła!

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Transient trajectory of journal in hydrodynamic bearing

Hirani H., Athre K., Biswas S.

Applied Mechanics and Engineering

2000

Vol. 5, no 2

405-418

A simple methodology to trace journal orbit under dynamic load conditions is presented. The non-linear fluid film bearing forces are derived using a closed-form two-dimensional pressure solution obtained from Reynolds equation for dynamic case. An implicit two-dimensional Newton-Raphson method is employed to determine journal center velocity by solving the equations of motion incorporating journal inertia and unbalance forces. A global technique is used to ensure convergence towards the root in each iteration. Finally, two connecting rod big end bearings are studied to demonstrate the effect of inertia forces at high speed.

Journal bearing design using TKSolver

Hirani H., Athre K., Biswas S.

Applied Mechanics and Engineering

1999

Vol. 4, no spec.

39-44

An easili adaptable design for journal bearing is furnished as an improvement over bearing design evaluated by trial and error method using many design charts. Guidelines are arranged to decide bearing length, clearance and bearing materials. Simplified closed form algebraic expressions are used to reduce computational time and cost for the prediction of maximum pressure, fluid film temperature rise, quantity of lubricant, friction loss, load zapacity and whirl onset velocity. Automatic iterative solving feature of TKSolver software is applied to extract eccentricity for a given load. The results of load, maximum pressure, friction loss, maximum temperature and attitude angle are given in tabular form over a range of eccentricity ratio to optimize bearing design.

Derivation of nonlinear coefficients in multi lobe journal bearings

Rao T. V. V. L. N., Biswas S., Athre K.

Applied Mechanics and Engineering

1999

Vol. 4, no spec.

57-66

The equivalent stiffness and damping coefficients calculated successively along the journal center locus with reference to the equilibrium position are obtained (in the case of stable journal orbit) using Taylor series expansion. To validate the accuracy of the derived coefficients, the journal orbit is compared with the transient simulation under similar operating conditions. The equivalent dynamic coefficients are further evaluated according to the modified journal position using linear interpolation procedure. The average value of the equivalent stiffness and damping coefficients are calculated at various perturbation amplitudes from equilibrium position along the transient orbit. The influence of journal center position and velocities is observed. With nonlinear coefficients close to actual simulation under stable conditions this methodology provides the bearing designer variation of dynamic coefficients in the bearings.