Conference Papers

Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506

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Author: search.filters.author.Kulkarni, A.S.

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    A New Forward Model Approach for a Mild Steel Fin under Natural Convection Heat Transfer
    (Elsevier Ltd, 2015) Kulkarni, A.S.; Kumar, H.; Gnanasekaran, N.
    This paper reports the correlation for temperature of the mild steel fin which is subjected to heat flux at its base. The study is performed on a two dimensional, steady state and laminar flow model. The numerical model is restricted to natural convection and the fluid under consideration is air. A rectangular mild steel fin (250 mm x 150 mm x 6 mm), aluminium base plate (250 mm x 150 mm x 8 mm) and an extended geometry representing the ambient air condition is modelled and simulated using ANSYS 14.5. Grid independence study is carried out to fix the number of grids in order to find the optimum number of nodes for carrying out simulations. The heat flux (q) at the bottom of the base plate is varied to study temperature distribution, surface heat transfer coefficient (h) and velocity profile of the flow in the boundary layer around the fin. All these parameters are studied by inclining the model at various angles. A multiple regression analysis is carried out to obtain correlation for the temperature in terms of angle of inclination and the heat flux. The main objective of the work is, proposing a model for the estimation of heat flux or heat transfer coefficient from the fin thereby reducing the computational cost of the forward model in the field of inverse heat transfer. © 2015 The Authors.
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    Design of an energy regenerative system for a robotic leg prosthesis
    (Institute of Electrical and Electronics Engineers Inc., 2018) Kulkarni, A.S.; Kulkarni, S.M.
    The number of lower limb amputations have significantly increased over the years and this calls for improvement in the technology of prosthetic devices. Compared to the rudimentary passively operated devices, the latest active prostheses require electrical energy supplied from the battery for various tasks like operating motors, clutches and microprocessors. The objective of this study is to increase the energy efficiency of the device by employing a mechanism which will help regenerate energy so that the system's dependence on an external battery is reduced. A crank slider mechanism is appended to the prosthetic leg and the linear motion of the slider is used to harness energy using the principle of electromagnetic induction. A permanent magnet is included in the slider which moves interior to a coil and generates a voltage. The mechanism will be actuated due to the motion of the knee motor. The supercapacitor technology is used to store and supply this energy at regular intervals. A dynamic simulation is carried out in MATLAB to investigate the energy regenerated in the prosthetic device while the amputee walks, runs, sprints or climbs the stairs up and down. Single and multiple coil models are designed and tested for best performance statistics. Also, extra energy spent by the motor to carry the weight of the mechanism and to overcome friction is computed. Analysis of all the above factors for various human motions will verify the usefulness of the proposed system and this will mark an establishment of an electrically regenerative robotic leg prosthesis. © 2017 IEEE.