D. Hanumanna

Bio: D. Hanumanna is an academic researcher. The author has contributed to research in topics: Vibration fatigue. The author has an hindex of 2, co-authored 2 publications receiving 8 citations.

Bending fatigue testing of gear teeth under random loading

Abstract: The gears in a gear box fitted in an armoured tracked vehicle for the purpose of power transmission and positioning of rotating heavy mass to the desired angle with high accuracy are subjected to fluctuating loads that are random in nature. One of the important modes of failure in cyclic loading conditions including random loads is fatigue failure. It is thus important from the design point of view to estimate the life of the gears under these conditions. The fatigue life of components subjected to sinusoidal loading can be estimated by using cumulative damage theories. Their extension to random load fatigue, though straightforward, may not be very accurate owing to inherent scatter exhibited by the fatigue phenomenon. It is therefore necessary experimentally to determine the fatigue life of randomly loaded components and establish the validity of the theoretical model. An electrohydraulic test rig has been designed and fabricated that is capable of generating different types of load pattern by ad...

Prediction of Fatigue Life of Gear Subjected to Varying Loads

Abstract: Structural members and components of a vehicle during service are subjected to varying loads which are random in nature. For structural members subjected to loads of constant amplitude, it is possible to describe the load with explicit mathematical relationship, and thereby, the life span can be estimated. Whereas, for structural members subjected to varying loads with time, there is no satisfactory method to estimate their life span. This paper describes a method for the estimation of life span of a gear in the gear box of a fighting vehicle subjected to fluctuating loads. For this purpose, it is assumed that the load spectrum corresponds to Gaussian (normal) distribution, and the life has been worked out by applying linear cumulative damage theory.

Estimation of Bending Fatigue Life of Hypoid Gears Using a Multiaxial Fatigue Criterion

Abstract: In this study, a crack initiation life prediction methodology for the tooth bending fatigue of hypoid gears is proposed. This methodology employs a previously developed finite-element based hypoid gear root stress model (Hotait et al. 2011, “An Investigation of Root Stresses of Hypoid Gears with Misalignments,” ASME J. Mech. Des., 133, p. 071006) of face-milled and face-hobbed hypoid gears to establish the multiaxial stress time histories within the root fillet regions. These stress time histories are combined with a multiaxial crack initiation fatigue criterion to predict life distributions along roots of the pinion and the gear. The predictions of the multiaxial fatigue model are compared to those from a conventional uniaxial fatigue model to establish the necessity for a multiaxial approach. The model is exercised with an example face-milled hypoid gear set from an automotive application to demonstrate the impact of various misalignments well as the key cutting tool parameters on the resultant tooth bending lives.

Multiaxial fatigue analysis of stranded-wire helical springs:

Abstract: In this paper, finite element method is implemented to model stranded-wire helical springs under different loading conditions. Finite element results are coupled with multiaxial fatigue criteria su...

A Theoretical and Experimental Investigation on Bending Strength and Fatigue Life of Spiral Bevel and Hypoid Gears

Abstract: .................................................................................................................................... ii DEDICATION ................................................................................................................................ iv ACKNOWLEDGMENTS ............................................................................................................... v VITA ............................................................................................................................................... vi PUBLICATIONS ............................................................................................................................ vi FIELDS OF STUDY....................................................................................................................... vi TABLE OF CONTENTS ............................................................................................................... vii LIST OF TABLES .......................................................................................................................... xi LIST OF FIGURES ....................................................................................................................... xii NOMENCLATURE ...................................................................................................................... xx TOOTH NOMENCLATURE ...................................................................................................... xxv CHAPTER 1 1.1 Background and Motivation .................................................................................................... 1 1.2 Literature Review..................................................................................................................... 4 1.2.1 Gear Root Stresses Prediction Models ............................................................................... 4 1.2.2 Influence of Misalignments on Gear Bending Stresses ..................................................... 7 viii 1.2.3 Gear Bending Fatigue Models ........................................................................................... 8 1.3 Scope and Objectives ............................................................................................................. 11 1.4 Dissertation Outline ............................................................................................................... 13 CHAPTER 2 2.

Enhancement of Fatigue Strength on SAE 1541 Steel Link Plate with Slip Ball Burnishing Technique

Abstract: This research paper describes a technique for the enhancement of the fatigue strength of the chain link plate in the drive system of a military armoured vehicle. SAE 1541 steel link plates of chains were subjected to cyclical tensile stress due to repeated loading and un-loading conditions. The crack was getting originated from the pitch hole and growth perpendicular to the chain pulling load, due to fatigue mechanism. In general plate holes are manufactured using the conventional process. An additional novel technique called the slip ball burnishing (SBB) method is applied for improving the hole properties. The improvement is made by producing local plastic deformation, improving surface finish and compressive residual stress throughout in the pierced hole. Both the conventional process (CP) and the SBB technique have been evaluated by optical, profile, surface roughness and micro harness tests. Experimental fatigue test validations were done in both chain samples using the Johnson-Goodman method. SBB chains passed 3x106 cycles at the load of 17.61 kN and CP chains passed 3x106 cycles at the load of 13.92 kN. The conclusion was that SBB made a significant improvement of 26.51 per cent of fatigue strength compared to CP.