Modeling hertzian stress in line contact by cilinder and plate. To study the vibration mechanism of ball bearings with localized defects, a vibration model of a ball bearing based on the hertzian contact stress distribution is proposed to predict the contact force and vibration response caused by a localized defect. Is it important to give the non linear behaviour to it. Hertz contact stress analysis and validation using finite. A central distinction in contact mechanics is between stresses acting perpendicular to the contacting. Technology fatigue analysis of deep groove ball bearing based. Dec 26, 2014 in general machines are designed with a set of elements to reduce cost, ease of assembly and manufacturability etc.
The typical results we want to see are the peak contact stress, the contact radius and stress. It was found that stress was more than the correct value. Contact mechanics is the study of the deformation of solids that touch each other at one or more points. Fea should converge, with finer element size, to this, where one can see the max.
Use of contact pair in ansys hertzian stresses on contact. Introduction when there are two nonconforming surfaces that come into contact the point or line of contact can be a location of very high stress. I found a nice paper giving the theoretical solution for a 2d plane strain problem here. The application performs all calculations automatically. For the free online simulation course from cornell university, ansys. We can also do wear analysis due to frictional rubbing between the contact surfaces. Ansys, on the other hand gave me good correlation between fea results of contact stress. A special geometrical configuration of the inner race along with rollers has. This page provides a free online calculation for hertzian contact stress for point and line contact including a diagram for subsurface stresses. Through contact analysis, the changes could be showed in stress. Pdf hertz contact stress analysis and validation using. A special geometrical configuration of the inner race along with rollers has been used to transmit the torque from one race to another race in one direction only due to wedging action developed at two contact regions. Contact stresses and deformations mechanical engineering.
As finite element method fem is the easy and accurate technique for stress analysis, fea is done in finite element. Contact stress analysis of spur gear for different. We will demonstrate how to check material selections. Contact stress analysis in wheelrail by hertzian method and finite element method. For the free online simulation course from cornell university, ansys student 2019 r3 is recommended. Applicability of the hertz contact theory to rolling rubber. In this analysis the factors consider fatigue life, hertzian stress, strain penetration. The spur gear is sketched and modelled in ansys design modeller and the contact stress analysis is done in mechanical ansys. In both cases, we are interested in the tooth load, which we. Tutorial on hertz contact stress university of arizona. It is difficult to get correct answer on gear tooth stress by implying fundamental stress equation, such as lewis formula for bending stress and hertz equation for contact stress.
The results which are obtained by solving the general equation of motion in ansys software are given in table 4. Contact stress analysis of spur gear ijert journal. Nov 28, 2018 the student community is a public forum for authorized ansys academic product users to share ideas and ask questions. Tutorial hertz contact stress brian taylor opti521 fall 2016, sid. It simply did not support contact stress calculations. I am trying to model hertz contact stress for a cylinder on a plane, but my fea pressure is less than a factor of 17 when comparing my calculations to the results. Tutorial hertz contact stress university of arizona. This demonstration presents the hertzian contact stress distribution and elastic deformations. The ansys code offers stress analysts a variety of contact element options. Earlier, i uploaded a question concerning a hertzian stress modeling problem. Recent versions of ansys workbench mechanical include detection of contact between line bodies and faces.
Department of mechanical engineering, younus college of engineering for women, kerala 691538, india. I am trying to model hertz contact stress for a cylinder on a plane, but my fea pressure is. The theory developed by hertz in 1880 remains the foundation for most contact problems. Arbitrary normal and tangential loading sequences for circular hertzian contact. The contact stress developed in the area of contact of the pinion and gear was calculated analytically by using finite element method ansys workbench release 14. In hertz stress calculator the data assumed for calculation provided as input for calculating contact stress is shown in fig. It uses a color function to visualize the contact zone between a statically loaded pair of contact models, a sphere and a torus. Hertz contact problem describes the behavior of a steel cylinder pressed into an aluminium block. Hertzian cone, the cone produced when an object passes through a solid, such as a bullet through glass. Hertz contact stress calculations and graphs with hertzwin. Evaluation of contact stresses in bearings made of al beryl.
This paper presents a study by the finite element method fem of the contact tensions between two bodies and the results obtained are compared with the calculations obtained on basis of the relations of the theory of h. For the analysis, steel and grey cast iron are used as the materials of spur gear. Modeling hertzian contact stress in line contact by two cylinders. The result obtained from hertz contact stress calculator is 266. Hertz equation is used to determine the contact stresses in the mating teeth of gear. Hertz contact stress analysis and validation using finite element analysis.
Pdf conditions for assuming hertzian stress for the contact. Hertz contact stress calculations hertzwin is a free hertzian contact stress calculator. Stress analysis of composite spur gear ijert journal. Ansys and hertz equation which is for finding contact stress in gears.
In this paper, the contact stress analysis of stainless steel spur gear by theoretical method using hertz equation and finite element analysis using ansys 16. Structural analysis software fea analysis ansys structural. Keywords hertz contact stress, contact fe analysis, stresses within rollers, roller contact analysis and hertz contact stress calculations. Oct 23, 2014 the typical results we want to see are the peak contact stress, the contact radius and stress variation through depth under peak contact stress. Abstract this paper investigates the static stress characteristics of an involute composite spur gear system including bending stresses and contact stresses of. Hertzian contact stress, localized stresses that develop as two curved surfaces come in contact and deform slightly under imposed loads. The photoelastic research of the hertzian stress in hcrgears lovrin, 2001 and the above presented results point at a general conclusion that the hertzian stresses in hcrgears are smaller than the. Applicability of the hertz contact theory to rolling. Procedia engineering 38 2012 264 269 equations for load bearing capabilities and fatigue life in bearings, gears, and other bodies where two.
The contact analysis for deep groove ball bearing based on ansys. I am not familiar with the different kinds of contacts in ansys, since i am just a beginner could you please help me out and tell me how to tackle. The hertz contact theory the hertz contact theory consists of a series of mathematical equations to calculate normal, hoop, radial, and shear stress components on and within a soft flat. Fluid flow and heat transfer analysis, ansys fluent tutorial. Sliding perpendicular to its axis and sliding spheres. If youre comparing bending stresses, for example, with a quarter of yield then by the same token the shear stress should be compared with one eighth of yield. Ansys student is used by hundreds of thousands of students globally. Dec 12, 2014 use of contact pair in ansys hertzian stresses on contact. Iii abstract this thesis investigates the characteristics of an involute gear system including contact stresses, bending stresses, and the transmission errors of gears in mesh. Hertzian contact stress analysis in roller power transmission. Pdf contact stress analysis in wheelrail by hertzian. The use of digital image correlation method in contact. Through contact analysis, the changes could be showed in stress, strain, penetration, sliding distance, friction stress among the inner ring, outer ring, rolling elements and cage.
Hertzwin is a free hertzian contact stress calculator. Method is preferable for contact stress analysis of involute spur gear 9, 10, 11. Fem results for contact stress of spur gear by ansys. Hertz contact theory hct is a study of contact stress and deformation which is widely used in many engineering fields. Apr 22, 20 step by step procedure of how to do static structural analysis of hertzian contact analysis ansys workbench. In detail study of the contact stress produced in the mating gears is the most important task in design of gears as it is the deciding. Investigation of the effects of profile shift in helical gear. The intuitive interface of ansys mechanical enables engineers of all levels to get answers fast and with confidence. A vibration model of ball bearings with a localized defect. The worn covers the analysis based on hertzian contact stresses. Stresses surface tractions and sliding contact cylinder. For 2d plane problem, a analytical stress solution can be actually obtained where the stress is inversely proportional to the root square of the distance to the tip.
Me 383s bryant february 17, 2006 9 hertzian contact theory compressive normal load p induces. Hertz contact stress mechanical engineering general. An approximate analytical model of hertzian theory is helpful to reduce calculation time in a design. Since the initial problem setup changed, i decided to open a new thread. Fea solution that provides robust, generalpurpose stress. Morning coffee jazz relaxing instrumental bossa nova jazz playlist have a nice day.
Over a century ago hertz established a theory of contact mechanics that is still used today by engineers working in tribology to make his theory accessible for engineering applications the program calculates a fast and accurate solution this demonstration presents the hertzian contact stress. For an electronic copy pdf of the relevant report, click here consider a simple problem that illustrates a comparison between the analytical and numerical results. Conditions for assuming hertzian stress for the contact between a circular pin and hole. Dec 06, 2016 hertz contact theory hct is a study of contact stress and deformation which is widely used in many engineering fields. Me en 7960 precision machine design contact stresses and deformations 7 sphere vs. Contact stress and shear stress analysis of spur gear using.
Contact stress analysis of spur gear for different materials using ansys and hertz equation putti srinivasa rao1, nadipalli sriraj2, mohammad farookh2 1professor, dept. Line to solid face contact simutech group ansys fea. The issue is once more to model the hertzian contact stress. Pdf hertz contact stress analysis and validation using finite. Large amount of stress is induced due to thermal load. Its also got a semidecent gui, which you can download for free. The conventional method of calculating gear contact stress using hertz s theory for verification by 2d fem analyzer using ansys, in later investigation the. Contact stress analysis of spur gear for different materials. Ansys structural analysis software enables you to solve complex structural engineering problems and make better, faster design decisions. Procedia engineering 38 2012 264 a 269 18777058 a 2012 published by elsevier ltd. Hertz contact mechanics physics setup simcafe dashboard. Ali raad hassan 4 analyzed contact stress, considering contact ratio, approach angle, recess angle, contact and length of contact. Step by step procedure of how to do static structural analysis of hertzian contact analysis ansys workbench.
X nomenclature k structural stiffness u displacement vector f applied load vector pmax maximum contact stress d1 pinion pitch diameter d2 gear pitch diameter fi load per unit width ri radius of cylinderi. It can be used to calculate mechanical point and line contact dimensions and material stresses. However, there are many limiting conditions for the applications of the hct, in this paper, the contact model between a plastic cylinder and a rubber cylinder does not fit two limiting conditions. The spur gears are sketched, modeled and assembled in ansys designmodeler. Hertzian contact stress wolfram demonstrations project. The shear stress limit is generally half the allowable stress intensity limit. Therefore, the aim of this study is to present the effect of rotational speed of gear on contact stress and comparison between the finite element numerical solution by ansys and theoretical hertzian method. For an electronic copy pdf of the relevant report, click here consider a simple problem that illustrates a comparison. Ansys wornbench was used as a tool to construct the model. Stress analysis on spur gears using ansys workbench 16. Arbitrary normal and tangential loading sequences for. The calculation of the ballraceway contact force when the ball passes over the defect is key to establishing a defect vibration model. International journal for research in applied science.
Here in, we report the contact stress analysis of stainless steel spur gears by theoretical method using hertz equations and. Hertzian equation for contact stress in the teeth of mating gears is given by, v. Maximum tooth root stress and hertzian contact stress for each solution is calculated. The present work is an attempt to find root bending stress distribution, maximum allowable contact stress. Contact stress distribution of large diameter ball bearing. From designers and occasional users looking for quick, easy and accurate results, to experts looking to model complex materials, large assemblies and nonlinear behavior, ansys has you covered. The student community is a public forum for authorized ansys academic product users to share ideas and ask questions. The issue is once more to model the hertzian contact stress in a rigid cylindrical element, pushing down on a flexible plate of the same material.
The distribution of stress on the teeth for couple and pinion in case of nonshifted gear mechanism are shown in figure 5. Contact stress analysis of spur gear under the different. One also needs to address stress issues at the contact regions between any two elements, stress is induced when a load is applied to two elastic solids in contact. Introduction when there are two nonconforming surfaces that come into contact the point or line of contact can be a location of very high stress values. Fea solution that provides robust, generalpurpose stress, thermal, vibration and fatigue simulations for fast and accurate solutions. Analysis fea are compared with theoretical hertzian equation values. It is a great choice if your professor is already using it for your course or if you are already familiar with the ansys workbench platform.
Hertz contact stress analysis and validation using finite element analysis 3,777 views. A roller oneway clutch is used for transmitting torque in one direction while running free in the reverse. Contact stress and shear stress analysis of spur gear. However, there are many limiting conditions for the applications of. Some time ago i have had a similar problem in calculating contact hertz stress in algor. The maximum shear stress obtained from ansys is 268. In this paper the bending stress over the lower addendum of the spur gear, shear and contact stresses by using the software tools like proe and ansys are employed to design and analysis.
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