Dynamic characteristics of turbine journal bearings

Imperial Users onl

Effect of variable friction coefficient on sheet metal drawing

A variable friction model that relates the parameters of sheet metal drawing to the local lubrication conditions taking place during the deformation, has been integrated to a finite element program. Variable friction coefficients for the contacting surfaces are determined from the friction model, which uses the related parameters obtained at each time step of the finite element program as inputs. A number of numerical runs have been performed and the strains are compared with the experimental results for circular blanks. A good agreement is obtained between the numerical and experimental results for the variable friction model used

Development of a knowledge-based system and a comparative study on the selection of bearings (c)

An intelligent software package to select beatings suitable for a given application is developed and tested for the purpose of improving design efficiency and elimination of human dependent expertise for conceptual design. The work includes creation and development of a knowledge base and a classification of bearings based on operating and environmental factors within the knowledge base structure. The selection process is automated by using an inference engine that is developed mainly for this purpose and a proper user interface is designed for engineering designers

Computerized analysis of parameters affecting shape and thickness in cold rolling of strip for soft materials

A conventional 4-Hi cold rolling mill configuration was modelled and a computer program was developed to analyze the effects of inlet thickness, width, desired exit thickness, symmetric and asymmetric jack forces, screw positions, tensions on the strip, roll geometries, and material properties on strip shape and thickness. For the analysis, the finite difference method was used as the discretization technique. The roll force was obtained by integrating the calculated roll-pressure over the are of contact, and elastic distortion of rolls due to the strip interaction was also considered, For determining inter-roll force, the compatibility equation between work and backup rolls was expressed in terms of work and backup roll axis deflection and work roll surface deformation. The second compatibility equation between work roll and strip was expressed in terms of work roll axis deflections, work roll surface deformation, and estimated strip thickness. The calculated thickness distribution was used for determining shape

MIOCENE TO PLIOCENE PALEOGEOGRAPHIC EVOLUTION OF TURKEY AND ITS SURROUNDINGS

Palaeogeographic studies suggest that the main mammal migration to Anatolia started in the late early to middle Miocene, following the closure of the Bitlis Ocean in southeastern Turkey. These animals, including hominoids, were able to mig-rate over the land bridge thus formed to Central and Western Anatolia where they settled. We discuss the Miocene to Pliocene palaeogeographic evolution of Turkey and its surroundings, in order to show what conditions were effective on this settlement