Blar i Department of Mechanical and Structural Engineering and Materials Science (TN-IMBM) på forfatter "Lemu, Hirpa G."
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Study of rail-wheel contact problem by analytical and numerical approaches
Sirata, Goftila; Lemu, Hirpa G.; Waclawiak, Krzysztof; Jelila, Yohanis D. (Peer reviewed; Journal article, 2021)This study presents the rail wheel contact problems under normal and tangential categories. Both analytical and numerical approaches were used for modelling, where the analytical approach assumed elliptical contact patches ... -
Study of the Characteristics of Acoustic Emission Signals.
Nguyen, Bao (Masteroppgave/UIS-TN-IMBM/2020;, Master thesis, 2020-07-15)This report aims to study the characteristics of signals collected by Acoustic Emission Testing (AET) and categorize them into types to detect yield. A literature survey of existing knowledge of AET and Acoustic Emission ... -
Study of the Effects of Alkali Treatment and Fiber Orientation on Mechanical Properties of Enset/Sisal Polymer Hybrid Composite
Bekele, Abera E.; Lemu, Hirpa G.; Jiru, Moera G. (Peer reviewed; Journal article, 2023-01)Abstract In the manufacturing process of innovative fiber-based composite materials, natural fibers are among the most commonly employed reinforcements. In this study, Enset/Sisal (E/S) fiber with a polyester matrix was ... -
Study of the Performance of Natural Fiber Reinforced Composites for Wind Turbine Blade Applications
Batu, Temesgen; Sirabizuh, Belete; Lemu, Hirpa G. (Peer reviewed; Journal article, 2020)Availability of some form of energy is essential for human survival and social development. However, the way energy has been generated within the last century has brought forward the quest for generation of energy without ... -
Thermal stress analysis of disc brake using analytical and numerical methods
Jiregna, Iyasu T; Lemu, Hirpa G. (Peer reviewed; Journal article, 2021)This article presents study of the thermal stress development in brake disc and the associated life cycle of the disc. The thermal stress analysis of disc brake under the first brake application and the influences of thermal ... -
A Three-Dimensional Elastic-Plastic Contact Analysis of Vickers Indenter on a Deep Drawing Quality Steel Sheet
Trzepiecinski, Thomasz; Lemu, Hirpa G. (Peer reviewed; Journal article, 2019)Three-dimensional finite element-based numerical analysis of Vickers indenter hardness test was conducted to investigate the effect of frictional conditions and material anisotropy on indentation results of deep drawing ... -
Topology optimization through stiffness/weight ratio analysis for a three-point bending test of additive manufactured parts
Garcia-Granada, Andres; Catafal-Pedragosa, Joan; Lemu, Hirpa G. (Peer reviewed; Journal article, 2019)Topology Optimization (TO) is a technique that allows for increasingly efficient designs and its objective is to maximize the performance of mechanical systems or structure in a variety of fields. Attempts to employ TO for ... -
Trends of using polymer composite materials in additive manufacturing
Regassa, Yohannes; Lemu, Hirpa G.; Sirabizuh, Belete (Peer reviewed; Journal article, 2019)Additive manufacturing (AM) technology is nowadays one of the advanced manufacturing technologies used to convert three dimensional product data to physical objects without any special tooling. The emergence of the technology ... -
Utilizing multiple criteria decision-making optimization methods to machine LM25Al/VC material under electro-discharge machining processes
Tolcha, Mesay Alemu; Lemu, Hirpa G. (Peer reviewed; Journal article, 2023)In this work, sparking electro-discharge machining (EDM) process parameters are optimized by using multiple criteria decision-making (MCDM) methods. The work piece utilized for the investigation was LM25 aluminum alloy ...