摘要:

The dynamic analysis of the journal bearing which supports the planets of an epicyclic gear stage is described. The analysis includes an assessment of the damping characteristics of the bearing, the stability, and the response of the planet to gear mesh interactions between the sun, the planet, and the ring gear. A digital program was developed which provides the numerical solution of the equations of motion by forward integration in time. The full nonlinear expressions have been used for both the hydrodynamic bearing forces and the gear mesh interaction forces. Centrifugal and Coriolis effects due to the planetary motion are taken into account. Numerical results for a PT6 reduction gearbox indicate that the bearing is highly stable and not adversely affected by gear mesh excitations.

ISSN:0569-8197    

DOI:10.1080/05698198308981481

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Isogeometrical phosphorus compounds, used as model oil additives, were selected to study the role of sulfur and phosphorus under increasingly severe lubrication conditions. A modified commercial test device has been applied to measure friction and wear. Application of Auger electron spectroscopy leads to a better understanding of the beneficial role of AW/EP additives. A general mechanism resulting in the formation of acid phosphates is proposed as the first step of tribofragmentation. Phosphorus seems to be mainly responsible for the load-carrying capability of reaction layers under the present experimental conditions. A reduction in the phosphorus concentration immediately leads to an increase of friction and wear.Presented at the 37th Annual Meeting in Cincinnati, Ohio, May 10–13, 1982

ISSN:0569-8197    

DOI:10.1080/05698198308981482

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Pivoted-pad journal bearings are commonly applied to highspeed rotating equipment because of their potential for stable operation. Analysis of such bearings is complicated by the ability of each pad to pivot as the shaft is displaced, and to translate radially due to pivot flexibility. This leads to dependence of linearized stiffness and damping coefficients on shaft vibrational frequency, as well as shaft rotational frequency. Pad inertia and mass effects also couple into the response of the bearing, and become significant in large bearings.

ISSN:0569-8197    

DOI:10.1080/05698198308981483

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The effects of phenolic antioxidants on the adsorption of the antiwear additive, dilinoleic acid, from dodecane onto metal surfaces have been measured. The adsorbents were the metals of the Lucas piston pump used in aviation fuel systems, viz cadmium, a tool steel and an aluminum bronze. For the latter two metals particularly, adsorption at 80°C and 100°C was enhanced by the presence of antioxidants. This is attributed to a reduction in the formation of solvent oxidation products which would otherwise compete for surface sites on the metals. Comparison of results at 150°C in air and under nitrogen support this interpretation. The role of the metal surface is discused both in terms of the nature of the adsorption sites and catalysis of reactions occurring in solution.

ISSN:0569-8197    

DOI:10.1080/05698198308981484

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The two-lobed configurations considered for the present study are: the elliptical bearing, offset-halves bearing and two other configurations which are geometrical variations of the first two bearing forms. A companion of their performance characteristics has been obtained by theoretical analysis. It has been shown that, unlike elliptical and offset-halves bearings, which have only limited range of effective dynamic performance, a two-lobe configuration can provide consistently good dynamic performance over a wide range of load conditions.

ISSN:0569-8197    

DOI:10.1080/05698198308981485

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The analysis of hydrodynamic bearings using non-Newtonian lubricants being presented in this paper is with a distinctly different approach. By integral averaging of the shear strain rate across the film, an averaged viscosity, which is only a function of the coordinates along the film, has been defined. This makes it possible to apply the usual form of Reynolds equation. The steady-state pressure distribution is established by an iteration scheme which refines the viscosity field in successive steps. The performance characteristics results obtained from the analysis for a plane journal bearing with non-Newtonian lubricant following cubic shear stress law, compare very well with the experimental and theoretical results available in the published literature.

ISSN:0569-8197    

DOI:10.1080/05698198308981486

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor