摘要:

In aiding engineers and material scientists to develop more wear resistant ceramics, the wear properties, wear characteristics, and modes of failure must be better understood. The purpose of this paper is to examine fundamentals of the wear of ceramics, to present methodology needed to describe wear mechanisms in ceramics, and to point out where experimental research is needed to guide theoretical work. The stresses at asperities and pores, and the stresses due to thermal gradients are briefly explored to show the complexity of developing wear models. Definitions of wear modes are proposed to clarify usage of terminology. Finally, research recommendations are given to aid present and future researchers who are presently investigating and planning on entering this field.Presented at the 42nd Annual Meeting in Anaheim, California May 11–14, 1987

ISSN:1040-2004    

DOI:10.1080/10402008908981855

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The mechanics of an active magnetic bearing (AMB) is explained by presenting a practical AMB control scheme. The scheme comprises three parallel feedback loops to achieve dynamic stiffness, static stiffness and damping. These AMB properties are presented for rotor/bearing designers in closed-form functions of exciting frequency and several electronically adjustable parameters. Furthermore, the scheme is translated into a set of first-order differential equations. Combining the AMB formulation with the conventional finite element rotordynamics formulation, a rigorous electromechanical system model is established for forced response and stability analyses.Presented at the 43rd Annual Meeting in Cleveland, Ohio May 9–12, 1988

ISSN:1040-2004    

DOI:10.1080/10402008908981856

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Electricity generated by nuclear power is now common in Japan. The present commercialized status of nuclear power generation technology has been established due to efforts of many engineers and also as a result of information accumulated from other advanced countries. Presently 23 percent of total electricity generated in Japan depends on nuclear power, and in the long run, this proportion is expected to increase further. Although accumulation of various important technological knowledge is required in nuclear power generation, the conversion of heat generated in nuclear reactors into electrical energy by means of a working medium is one of the most essential problems in the relevant technology. This paper deals with rotary shaft seals used in the circulation pump for the primary coolant, as an important functioning component in such a system. Once this sealing system causes trouble such as excessive leakage, it results in quite serious social problems; i.e., not only power failure but also possibly radioactive contamination.

ISSN:1040-2004    

DOI:10.1080/10402008908981857

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Discussion and closures to above titled paper published October, 1988, 427–436.

ISSN:1040-2004    

DOI:10.1080/10402008908981858

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Past and recent experience indicates that a wide spectrum of tribological interactions cannot be treated by the separate approaches that have always been assigned to hydrodynamic action on one hand and dry friction on the other hand. Experimental evidence from the literature and from the authors' recent experiments is cited for the support of a hypothesis that both morphological and hydrodynamic effects are at work in all interactions and that only their respective ratios differ from regime to regime. Assigning to thick fluid films morphological phenomena and to wear particles a quasi-hydrodynamic behavior, a unified mechanism is postulated for generating load capacity between all tribologically interacting surfaces.Presented at the 43rd Annual Meeting in Cleveland, Ohio May 9–12, 1988

ISSN:1040-2004    

DOI:10.1080/10402008908981859

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The lubricating properties of “tribo-coating” films of Pb-Sn alloys with various compositions were studied in a vacuum of 10−6Pa. The ring specimen was coated by tribo-coating which forms an adhesive transfer film by pressing a film material onto the rotating substrate.

ISSN:1040-2004    

DOI:10.1080/10402008908981860

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

The transient characteristics of an infinite tilted-pad thrust bearing are studied numerically for a step change in the slider velocity. Numerical solutions indicate that the effect of temperature-dependent viscosity is to lower the temperature of the lubricant film and reduce the load capacity and drag. This is particularly true for lower vlaues of the modified Reynolds number. It is also shown that the transient characteristics depend on the initial condition of the bearing and on the terminal speed of the slider.

ISSN:1040-2004    

DOI:10.1080/10402008908981861

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

In this paper the stability chart of a linearized self-acting gas journal bearing is assessed by tracing the response of a journal accelerated from an equilibrium state. The response is obtained by the simultaneous time marching solution of the time-transient Reynolds equation and the equations of motion of the journal. For this purpose, the Reynolds equation is cast as an initial value problem via Galerkin's finite element method.

ISSN:1040-2004    

DOI:10.1080/10402008908981862

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

This paper is concerned with the theoretical investigations of the practical problem of the response of plane hydrodynamic journal bearing systems during acceleration and deceleration periods. The nature of the theoretically predicted journal response during starting and stopping is found to be similar to the experimental behavior reported by other authors. The motion of an accelerating or a decelerating journal shows concurrence with the linearized stability chart. An interesting finding is that, beginning from an equilibrium state, a journal can be accelerated only to a limiting value so that it may return to its original state on being decelerated from the accelerated speed.

ISSN:1040-2004    

DOI:10.1080/10402008908981863

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor

摘要:

Tribochemical reactions of dibenzyl disulfide tested binary blends and with additives including zinc diisobutyldithiophosphate, chlorinated paraffin, basic barium alkylbenzylsulfonate, 2,6-ditert-butyl-4-methyl phenol, octadecylamine, diphenylamine and the polysisobutenylsuccinimide of triethylenetetraamine in binary additive systems tested in white oil are investigated.

ISSN:1040-2004    

DOI:10.1080/10402008908981864

出版商:Taylor & Francis Group    

年代:1989

数据来源: Taylor