Extending the Capabilities of Hertz Equation Through Theoretical and Experimental Method

Contact analyses have been conducted over more than one century starting with Hertz who analyzed normal frictionless elastic contact between half-spaces with small deformation. The phenomenon of two surfaces in contact is important in the field of tribology and has been studied my many researchers. Hollow roller bearings find wide applications owing to their lower inertia, better radial stiffness and cooler running. The preloading of the rollers ensures many superior operating characteristics such as higher radial stiffness, rotational accuracy and higher speed capability. For hollow roller method is available for the calculation of contact width and contact stresses and all other important terminologies which are available for the solid roller. This paper presents a numerical and experimental analysis of the contact interaction between two elastic bodies “Cylinder and Flat”. In the numerical analysis Hertz theory is used to determine contact width for elastic contact. Experimental investigation has been performed by footprint method which is used to analyze a real contact area between two bodies for applied loading conditions. A comparison with the numerical data is given to validate the experimental procedure. The test results are almost similar and very close with the numerical data. Using this experimental method elastic contact between hollow cylinder and flat has been studied. Finally in the present work modified Hertz equation was developed for the calculation of half contact width for hollow cylinder and cylinder/flat body contact.