Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
2 results
Search Results
Item Design and simulation of high pressure piezohydraulic pump with active valves(Institute of Electrical and Electronics Engineers Inc., 2016) Rao, S.N.; Rao, R.Pumps incorporated with active valves provide active control on both the inlet and outlet valves. Here piezoelectric actuation is used as the actuation system since piezoelectric actuators can produce controlled actuation. Also piezoelectric actuators can produce high displacement with large force and has advantages such as high resolution, fast response, high stability, high reliability, compactness etc. In this work active valves are designed for a high pressure piezo-hydraulic pump. Flexural amplifiers for piezoelectric actuators are designed for the valve diaphragm actuation as well as for the pumping diaphragm actuation. There are three slotted diaphragms designed and operated by three separate flexurally amplified piezoelectric actuators. The flexural amplifiers and the diaphragms are analysed using ANSYS analysis software. Suitable mathematical model is developed using MATLAB software for synchronizing the sequence of actuation with respect to timing. Here Bouc-Wen model is made use for modelling the hysteresis effect. MATLAB Simulink is used to develop the model and simulations are performed to determine the displacement produced by the piezoelectric actuators when applied with a voltage. Also simulations are carried out for the determination of pumped volume, flow rate and stroke length of a particular cylinder. © 2016 IEEE.Item Experimental investigation and artificial neural network-based modeling of batch reduction of hexavalent chromium by immobilized cells of newly isolated strain of chromium-resistant bacteria(2012) Shetty K, K.V.; Namitha, L.; Rao, S.N.; Narayani, M.The batch bioreduction of Cr(VI) by the cells of newly isolated chromium-resistant Acinetobacter sp. bacteria, immobilized on glass beads and Ca-alginate beads, was investigated. The rate of reduction and percentage reduction of Cr(VI) decrease with the increase in initial Cr(VI) concentration, indicating the inhibitory effect of Cr(VI). Efficiency of bioreduction can be improved by increasing the bioparticle loading or the initial biomass loading. Glass bioparticles have shown better performance as compared to Ca-alginate bioparticles in terms of batch Cr(VI) reduction achieved and the rate of reduction. Glass beads may be considered as better cell carrier particles for immobilization as compared to Ca-alginate beads. Around 90% reduction of 80 ppm Cr(VI) could be achieved after 24 h with initial biomass loading of 14.6 mg on glass beads. Artificial neural networkbased models are developed for prediction of batch Cr(VI) bioreduction using the cells immobilized on glass and Ca-alginate beads. © Springer Science+Business Media B.V. 2011.