Browsing by Author "Murthy, A.A."

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    Dynamic performance of magnetorheological Elastomer isolators for adaptive torsional vibration control in SDoF Systems: An experimental study
    (Elsevier B.V., 2025) Shenoy, P.; Murthy, A.A.; Gangadharan, K.V.; Patil, I.S.
    This paper presents an experimental investigation into the application of Magnetorheological Elastomer (MRE) isolators for torsional vibration isolation in a Single Degree of Freedom (SDoF) system. First, the characteristics have been extensively studied under torsional shear, followed by the derivation of the Parametric modeling for the system parameters using a fractional derivative-based Poynting-Thomson model. After investigating the dynamic properties of Magnetorheological Elastomers, an experimental test was custom-built using a MRE isolator for torsional vibration isolation in a single degree of freedom (SDoF) system. The system's input and output angular displacements were measured using the Serial Arrangement of Accelerometers (SAA) technique, which accurately captures the torsional modes of the system. The reduction in the system's transmissibility ratios, a measure of vibration isolation ability, was used to assess the effectiveness of the MRE isolators. The experimental results show that the system's natural Frequency shifts noticeably in response to different magnetic fields, significantly lowering transmissibility ratios. The impact of damping on the system was also investigated despite some discrepancies in the patterns. Results highlight a reduction in the amplitude transmissibility to 37.36 %. Co-relating to the field-dependent increase in the Stiffness, a frequency shift of 3 Hz is also observed. © 2025 The Authors
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    Theoretical, CFD modelling and experimental investigation of a four-intersecting-vane rotary expander
    (Elsevier Ltd, 2024) Murthy, A.A.; Krishan, G.; Shenoy, P.; Patil, I.S.
    Expansion devices significantly impact the performance of the Vapor Compression Refrigeration system and Organic Rankine Cycles. Its improvement has been identified as one of the most crucial parts of future studies. The experiments were carried out using an improved experimental rig with direct coupling of the prototype and the dynamometer. This is done to correct any misalignments caused by external forces. The internal pressure in the working chambers was measured using six pressure transducers at various locations on the expander. A three-dimensional computational fluid dynamics and theoretical model was developed to investigate the effect of losses and inherent physical processes on the prototype. The actual geometry of the stator is taken in the computational fluid dynamics model. Conversely, employing the equation for an irregular stator shape in the theoretical model is difficult. Therefore, a circular stator is considered. The experimental results were used to validate the developed models. The prototype was tested up to 1550 rpm rotating speed, 5 bar (abs) suction pressure, and 1 bar discharge pressure (abs). The computational fluid dynamics and theoretical model results showed that though the volumetric and adiabatic efficiency was generally overpredicted, the trends were very closely predicted. The computational fluid dynamics and the theoretical model could predict the volumetric and adiabatic efficiency with a variance of <19.5% and 14.7%, respectively, for most of the experimental data points. © 2023