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R. B. Howarth

Bio: R. B. Howarth is an academic researcher from University of Salford. The author has contributed to research in topics: Bearing (mechanical). The author has an hindex of 2, co-authored 2 publications receiving 75 citations.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the onset and development of wear in plain hydrodynamic journal bearings under repeated cycles of starting and stopping has been studied experimentally and it was found that the wear caused easily discernable but localized changes in diametral clearance, surface finish, and roundness of the bearing's bore.
Abstract: The onset and development of wear in plain hydrodynamic journal bearings under repeated cycles of starting and stopping has been studied experimentally. The wear which occurred caused easily discernable but localized changes in diametral clearance, surface finish, and roundness of the bearing's bore and these changes were measured after various numbers of operating cycles had been completed. Study of the location, within the bearings of the wear which arose, showed that it was caused entirely by the sliding which occurred during starting and that no significant contribution to the wearing process was made during stopping. It was also observed that, once an initial rapid phase of wearing was completed, the surface finish of the hardened steel shaft was reproduced in the regions of the bearing's surface which continued to be worn.

51 citations

Journal ArticleDOI
TL;DR: In this article, the behavior of plain, hydrodynamic journal bearings during starting and stopping under a steady load was investigated and the starting behavior indicated that a rapid buildup of hydrodynamynamic forces occurred in all cases.
Abstract: The work described is concerned with the behavior of plain, hydrodynamic journal bearings during starting and stopping under a steady load. The starting behavior indicated that a rapid buildup of hydrodynamic forces occurred in all cases. A hydrodynamic film was formed in a very short time, after which the shaft moved in a spiral shaped whirling locus to the steady state operating position. Prior to separation of the shaft and bearing surfaces, the contact was mainly a sliding situation with little or no initial rolling. At stopping, the shaft followed a typical hydrodynamic locus until rotation ceased and then a squeeze film trajectory to the final resting position.

32 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, a mixed lubrication analysis of sea-water lubricated journal bearing has been attempted to solve the problem of bearing wear, a computer code was written to estimate lubricating film thickness for a given set of load and speed condition, and to predict the lubrication regime for the specified surface roughness parameters.

114 citations

Journal ArticleDOI
TL;DR: In this paper, the effects of geometric change due to wear on the dynamic characteristics of journal bearings are determined theoretically in both laminar and turbulent regimes, and the numerical results for various wear depth parameters are indicated in graphical form.
Abstract: The effects of geometric change due to wear on the dynamic characteristics of journal bearings are determined theoretically in both laminar and turbulent regimes. The dynamic characteristics such as spring and damping coefficients and whirl onset speed of a rigid rotor supported by two identical symmetrically aligned bearings are analyzed by a semianalytical finite element method, and the numerical results for various wear depth parameters are indicated in graphical form. The geometric change due to wear has significant effects on the principal spring coefficients and on the cross-coupled damping coefficients. The whirl onset speed for a worn journal bearing whose wear depth parameter is larger than 0.3 becomes higher than the speed for a nonworn bearing.

85 citations

Journal ArticleDOI
01 Apr 1996-Wear
TL;DR: In this paper, the effects of geometric change due to wear on stability of hydrodynamic turbulent journal bearings have been investigated numerically, following Constantinescu's turbulent lubrication theory.

56 citations

Journal ArticleDOI
TL;DR: In this article, the authors present a wear analysis procedure and the wear calculation of journal bearings for a stripped-down single cylinder engine during start-up and coast-down, assuming that a steady load is applied to the journal bearings.

53 citations

Journal ArticleDOI
TL;DR: In this paper, the onset and development of wear in plain hydrodynamic journal bearings under repeated cycles of starting and stopping has been studied experimentally and it was found that the wear caused easily discernable but localized changes in diametral clearance, surface finish, and roundness of the bearing's bore.
Abstract: The onset and development of wear in plain hydrodynamic journal bearings under repeated cycles of starting and stopping has been studied experimentally. The wear which occurred caused easily discernable but localized changes in diametral clearance, surface finish, and roundness of the bearing's bore and these changes were measured after various numbers of operating cycles had been completed. Study of the location, within the bearings of the wear which arose, showed that it was caused entirely by the sliding which occurred during starting and that no significant contribution to the wearing process was made during stopping. It was also observed that, once an initial rapid phase of wearing was completed, the surface finish of the hardened steel shaft was reproduced in the regions of the bearing's surface which continued to be worn.

51 citations