Sharif University of TechnologyScientia Iranica1026-309831820240601Experimental and numerical analysis of novel 9-DOF robotic manipulator for computed tomography guided medical procedure6196312358710.24200/sci.2024.58941.5984ENSh.Kamlesh ShahSchool of Mechanical Engineering, KIIT Deemed to be University, Bhubaneswar-751024, India.R.MishraSchool of Mechanical Engineering, KIIT Deemed to be University, Bhubaneswar-751024, India.Journal Article20210826One of the most common procedures implemented in the diagnosis of cancer and tumour is percutaneous biopsy under computed tomography (CT) image guidance. A 9-DOF hybrid redundant fully actuated robotic manipulator with a novel arc and train design is developed here for the retrieval of suspected tissue for biopsy procedure under CT guidance. Mathematical model, forward, inverse kinematics and joint trajectory equations of the robotic manipulator is formulated using standard DH convention. Inverse kinematics of the novel arc and train structure for CT bed mountability is also derived in this research. 3D-CAD model of the robot is developed and compared with the CT machine and a human model in SolidWorks 2016. Theoretical simulation is performed using the derived equations in MATLAB. Target for the simulation and experimentation is obtained from CT image with the help of an expert radiologist in KIMS hospital, Bhubaneswar. Five experiments is performed using the target point to understand the repeatability of the robotic manipulator. Deviation analysis of the robot in reaching the target during experimentation is obtained and plotted using a dual camera setup and internal position sensors of the actuator. The experimental results were well within acceptable parameters under laboratory conditions.https://scientiairanica.sharif.edu/article_23587_79c6a4a0aa2acd3606b9188db00dfa2f.pdfSharif University of TechnologyScientia Iranica1026-309831820240601Peristaltic motion of non-Newtonian fluid under the influence of inclined magnetic field, porous medium, and chemical reaction6326452349010.24200/sci.2024.59484.6270ENR.VijayaragavanThiruvalluvar University, Serkadu,, Vellore, Tamilnadu, 632 115, IndiaP.TamizharasiThiruvalluvar University, Serkadu,, Vellore, Tamilnadu, 632 115, IndiaA.MageshJEI Mathaajee College of Engineering, Kanchipuram, 631 552, India.Journal Article20211130In this article, we studied the peristaltic motion of Jeffrey fluid with porous medium through an asymmetric channel under the influence of velocity slip parameters. Governing equations for non-Newtonian fluid flow models such as continuity, momentum, energy and mass transfer equations are formulated. Externally applied inclined magnetic field is also considered in the flow pattern. The lengthy governing equation of fluid motion is reduced by taking into the account of approximation of longer wavelengths and smaller Reynolds numbers The resulting governing equations are solved exactly. The graph shows the results of the impact of various related fluid parameters such as Hartmann number, Darcy number, Jeffrey fluid parameter, amplitude ratio, chemical reactions of fluid velocity, temperature, concentration, pressure rise, pressure gradient, streamlines etc. Finally, the various waveforms of the trapping phenomenon are presented.https://scientiairanica.sharif.edu/article_23490_9c4b86bef94d61db974804e80924765b.pdfSharif University of TechnologyScientia Iranica1026-309831820240601A study on the effect of the die transverse angle and the part rotational feed angle in the cold radial forging process of rods6466582319210.24200/sci.2023.59533.6295ENM.Fattahpoor RoushanDepartment of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, IranH.AfrasiabDepartment of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran.R. A.Jafari TalookolaeiDepartment of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran.Journal Article20211209Radial forging is an efficient and high-precision process for manufacturing rotary parts such as shafts, axles, and gun barrels. While this process has been extensively investigated in the literature, effect of some parameters like the die transverse angle and the part rotational feed angle has not been adequately studied since simulating several steps of this process with a full three-dimensional model is required for this purpose which is labor-intensive and time-consuming. To bridge this gap, in this paper a three-dimensional nonlinear finite element model has been developed to analyze effects of the die transverse angle and part rotational feed angle in this process. To address the lack of reliable experimental data in the literature, an innovative approach has been proposed and used for validation of the developed finite element model. It has been observed that dies with transverse angle of 155ᵒ and 165ᵒ provide the best performance in producing a part geometry close to the desired shape. However, the most uniform residual stress distribution is obtained in forging by a die with a smaller transverse angle. Furthermore, for improving the shape and quality of the final product, the part rotational feed angle should be reduced as much as possible.https://scientiairanica.sharif.edu/article_23192_36d402cb8aa8ec5fc5aaee2797b947fb.pdfSharif University of TechnologyScientia Iranica1026-309831820240601Python programming predictions of thermal behavioral aspects of orange peel and coconut-coir reinforced epoxy composites6596662327010.24200/sci.2023.60206.6665ENS.PujariDepartment of Mechanical Engineering, Lendi Institute of Engineering and Technology, Vizianagaram, 535005, India.P.AlekyaDepartment of Mechanical Engineering, Lendi Institute of Engineering and Technology, Vizianagaram, 535005, India.S.SivaraoUniveFaculty of Manufacturing Engineering, University Teknikal Malaysia, 76100 Durian Tunggal, Melaka, Malaysiasity Teknikal MalaysiaM.D.Silas KumarDepartment of Mechanical Engineering, Lendi Institute of Engineering and Technology, Vizianagaram, 535005, IndiaJournal Article20220403Using a hand lay-up approach, both orange peel and coconut coir fibres are used in particulate form with an epoxy matrix to create partly green biodegradable composites. The findings indicate great opportunities for employing these natural fibres. The thermal conductivity of orange peel and coconut-coir epoxy composites was measured experimentally for various volume fractions of particulate fibres. The experimental findings show that as fibre concentration increases, thermal conductivity decreases. Experimental data are compared to theoretical models to determine the change in thermal conductivity with fibre amount fraction.There was a clear correlation between the hypotheses and the actual results. Regression analysis using Python programming is also done for the prediction of the thermal properties of particulate orange peel and coconut-coir fibre composites. It is observed that coir fibre composites outperformed the orange peel, indicating that the coir fibre composite is a proper thermal insulator that can be used in many industries, like the automotive industry, buildings, and steam pipes, to reduce heat transfer and thereby save a lot of energy.https://scientiairanica.sharif.edu/article_23270_ac0fb9d43ec4059253bb1e96cf4eed29.pdfSharif University of TechnologyScientia Iranica1026-309831820240601Effect of surface topology and wettability on impacting droplet dynamics at moderate Reynolds numbers6676802352210.24200/sci.2024.58837.5990ENE.EzzatneshanFaculty of New Technologies and Aerospace Engineering, Shahid Beheshti University, Tehran, IranA.FattahiFaculty of New Technologies and Aerospace Engineering, Shahid Beheshti University, Tehran, IranA.KhosroabadiFaculty of New Technologies and Aerospace Engineering, Shahid Beheshti University, Tehran, IranJournal Article20210829The present work aims to investigate the effect of surface topology and wettability on the impacting droplet dynamics at different flow conditions. A multiphase lattice Boltzmann method (LBM) is employed for the simulation of interfacial dynamics. Firstly, the results obtained based on the present method for some benchmark two-phase flow problems are validated. Then, three surface topologies, including a flat substrate, semicircular cavity, and semicircular bump, are considered to get insight into the physical treatment of the impacting droplet. The present study shows that although the surface topology affects the spreading and rebounding processes of the impacting droplet, the hydrophilicity plays a significant role in the final form of the liquid phase and dictates a similar treatment for all the studied topologies. Considering different sizes for the bump, it is found that the shape of the droplet deforms almost the same immediately after the impaction for all the bump sizes and the spreading process is not affected by the wettability. However, the receding dynamics is significantly affected by the bump size and the wetting condition of the bump surface. It is found that the contact time is minimized by increment the bump size and hydrophobicity of the surface.https://scientiairanica.sharif.edu/article_23522_8d8d9be29af9ae508cb1645d9c147d7c.pdf