Browsing by Author "Singh, A.K."

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A New Single-Source Nine-Level Quadruple Boost Inverter (NQBI) for PV Application
(Institute of Electrical and Electronics Engineers Inc., 2022) Singh, A.K.; Raushan, R.; Mandal, R.K.; Ahmad, M.W.
Multi-level inverters (MLIs) with switched capacitors are becoming popular due to their utilization in AC high-voltage applications as well as in the field of renewable energy. To achieve the required magnitude of output voltage, the switched capacitor (SC) technique employs a lesser number of DC sources in accordance with the voltage across the capacitor. Designing an efficient high-gain MLI with fewer sources and switches needs a rigorous effort. This paper introduces a prototype of a nine-level quadruple boost inverter (NQBI) topology powered by one solar photo-voltaic source using fewer capacitors, switches, and diodes when compared to the other SC-MLIs topology. The suggested NQB inverter produces nine levels of voltage in its output by efficiently balancing the voltages of the two capacitors. The various SC-MLIs are compared in order to highlight the benefits and drawbacks of the proposed nine-level quadruple boost inverter (NQBI) topology. To validate the efficacy of the proposed solar photovoltaic based NQBI without grid connection, detailed experimental results are presented in a laboratory setting under various test conditions. © 2013 IEEE.
Additive Manufacturing of Syntactic Foams: Part 1: Development, Properties, and Recycling Potential of Filaments
(Minerals, Metals and Materials Society 184 Thorn Hill Road Warrendale PA 15086, 2018) Singh, A.K.; Patil, B.; Hoffmann, N.; Saltonstall, B.; Doddamani, M.; Gupta, N.
This work focuses on developing filaments of high-density polyethylene (HDPE) and their hollow particle-filled syntactic foams for commercial three-dimensional (3D) printers based on fused filament fabrication technology. Hollow fly-ash cenospheres were blended by 40 wt.% in a HDPE matrix to produce syntactic foam (HDPE40) filaments. Further, the recycling potential was studied by pelletizing the filaments again to extrude twice (2×) and three times (3×). The filaments were tensile tested at 10?4 s?1, 10?3 s?1, and 10?2 s?1 strain rates. HDPE40 filaments show an increasing trend in modulus and strength with the strain rate. Higher density and modulus were noticed for 2× filaments compared to 1× filaments because of the crushing of some cenospheres in the extrusion cycle. However, 2× and 3× filament densities are nearly the same, showing potential for recycling them. The filaments show better properties than the same materials processed by conventional injection molding. Micro-CT scans show a uniform dispersion of cenospheres in all filaments. © 2018, The Minerals, Metals & Materials Society.
Additive Manufacturing of Syntactic Foams: Part 2: Specimen Printing and Mechanical Property Characterization
(Minerals, Metals and Materials Society 184 Thorn Hill Road Warrendale PA 15086, 2018) Singh, A.K.; Saltonstall, B.; Patil, B.; Hoffmann, N.; Doddamani, M.; Gupta, N.
High-density polyethylene (HDPE) and its fly ash cenosphere-filled syntactic foam filaments have been recently developed. These filaments are used for three-dimensional (3D) printing using a commercial printer. The developed syntactic foam filament (HDPE40) contains 40 wt.% cenospheres in the HDPE matrix. Printing parameters for HDPE and HDPE40 were optimized for use in widely available commercial printers, and specimens were three-dimensionally (3D) printed for tensile testing at strain rate of 10?3 s?1. Process optimization resulted in smooth operation of the 3D printer without nozzle clogging or cenosphere fracture during the printing process. Characterization results revealed that the tensile modulus values of 3D-printed HDPE and HDPE40 specimens were higher than those of injection-molded specimens, while the tensile strength was comparable, but the fracture strain and density were lower. © 2018, The Minerals, Metals & Materials Society.
Additive Manufacturing of Three-Phase Syntactic Foams Containing Glass Microballoons and Air Pores
(Minerals, Metals and Materials Society 184 Thorn Hill Road Warrendale PA 15086, 2019) Singh, A.K.; Deptula, A.J.; Anawal, R.; Doddamani, M.; Gupta, N.
High-density polyethylene and its syntactic foams reinforced with 20 vol.% and 40 vol.% glass microballoons were 3D printed using the fused filament fabrication method and studied for their compressive response. The three-phase microstructure of syntactic foams fabricated in this work also contained about 10 vol.% matrix porosity for obtaining light weight for buoyancy applications. Filaments for 3D printing were developed using a single screw filament extruder and printed on a commercial 3D printer using settings optimized in this work. Three-dimensional printed blanks were machined to obtain specimens that were tested at 10 ?4 s ?1 , 10 ?3 s ?1 , 10 ?2 s ?1 and 1 s ?1 strain rates. The compression results were compared with those of compression-molded (CM) specimens of the same materials. It was observed that the syntactic foam had a three-phase microstructure: matrix, microballoons and air voids. The air voids made the resulting foam lighter than the CM specimen. The moduli of the 3D-printed specimen were higher than those of the CM specimens at all strain rates. Yield strength was observed to be higher for CM samples than 3D-printed ones. © 2019, The Minerals, Metals & Materials Society.
Composites of Lignin-Based Biochar with BiOCl for Photocatalytic Water Treatment: RSM Studies for Process Optimization
(MDPI, 2023) Singh, A.K.; Giannakoudakis, D.A.; Arkas, M.; Triantafyllidis, K.S.; Nair, V.
Textile effluents pose a massive threat to the aquatic environment, so, sustainable approaches for environmentally friendly multifunctional remediation methods degradation are still a challenge. In this study, composites consisting of bismuth oxyhalide nanoparticles, specifically bismuth oxychloride (BiOCl) nanoplatelets, and lignin-based biochar were synthesized following a one-step hydrolysis synthesis. The simultaneous photocatalytic and adsorptive remediation efficiency of the Biochar–BiOCl composites were studied for the removal of a benchmark azo anionic dye, methyl orange dye (MO). The influence of various parameters (such as catalyst dosage, initial dye concentration, and pH) on the photo-assisted removal was carried out and optimized using the Box–Behnken Design of RSM. The physicochemical properties of the nanomaterials were characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, thermogravimetric analysis, nitrogen sorption, and UV–Vis diffuse reflectance spectroscopy (DRS). The maximum dye removal was observed at a catalyst dosage of 1.39 g/L, an initial dye concentration of 41.8 mg/L, and a pH of 3.15. The experiment performed under optimized conditions resulted in 100% degradation of the MO after 60 min of light exposure. The incorporation of activated biochar had a positive impact on the photocatalytic performance of the BiOCl photocatalyst for removing the MO due to favorable changes in the surface morphology, optical absorption, and specific surface area and hence the dispersion of the photo-active nanoparticles leading to more photocatalytic active sites. This study is within the frames of the design and development of green-oriented nanomaterials of low cost for advanced (waste)water treatment applications. © 2023 by the authors.
Compressive behavior of cenosphere/hdpe syntactic foams under different strain rates
(2016) Kumar, B.R.B.; Singh, A.K.; Doddamani, M.; D, Luong, D.; Gupta, N.
An industrial scale injection molding machine is used to prepare fly ash cenosphere reinforced high density polyethylene (HDPE) syntactic foams. Thermosetting matrix foams with glass microspheres are being used in marine and aerospace applications owing to higher specific properties. Thermoplastic matrix syntactic foams have not been studied extensively despite interest in them for lightweight underwater vehicle structures and consumer products. Syntactic foams are fabricated with 20 and 40% cenospheres by weight. The studies on the manufacturing process suggest that a small percentage of cenospheres fracture in syntactic foams containing up to 40 wt.% cenospheres. Incorporation of particles, which are inexpensive, helps in fabricating low cost syntactic foams. Quasi-static compression tests are conducted at 10-4, 10-3 and 10-2 s-1 strain rates. The compressive strength of syntactic foams is higher than that of HDPE resin at the same strain rate due to the incorporation of ceramic particles. Yield strength shows an increasing trend with strain rate.
Compressive behavior of cenosphere/hdpe syntactic foams under different strain rates
(DEStech Publications Inc. info@destechpub.com, 2016) Kumar, B.R.B.; Singh, A.K.; Doddamani, M.; D Luong, D.; Gupta, N.
An industrial scale injection molding machine is used to prepare fly ash cenosphere reinforced high density polyethylene (HDPE) syntactic foams. Thermosetting matrix foams with glass microspheres are being used in marine and aerospace applications owing to higher specific properties. Thermoplastic matrix syntactic foams have not been studied extensively despite interest in them for lightweight underwater vehicle structures and consumer products. Syntactic foams are fabricated with 20 and 40% cenospheres by weight. The studies on the manufacturing process suggest that a small percentage of cenospheres fracture in syntactic foams containing up to 40 wt.% cenospheres. Incorporation of particles, which are inexpensive, helps in fabricating low cost syntactic foams. Quasi-static compression tests are conducted at 10-4, 10-3 and 10-2 s-1 strain rates. The compressive strength of syntactic foams is higher than that of HDPE resin at the same strain rate due to the incorporation of ceramic particles. Yield strength shows an increasing trend with strain rate.
Development of glass microballoon/HDPE syntactic foams by compression molding
(Elsevier Ltd, 2017) Jayavardhan, M.L.; Bharath Kumar, B.R.; Doddamani, M.; Singh, A.K.; Zeltmann, S.E.; Gupta, N.
Thermoplastic resins are widely used in consumer products and industrial components. There is a significant interest in weight reduction of many of those components. Although glass hollow particle filled lightweight syntactic foams with thermoset matrices have been studied in detail, studies on thermoplastic syntactic foams are scarce. The present study is focused on developing a compression molding based processing method for glass microballoon/high density polyethylene (GMB/HDPE) syntactic foams and studying their mechanical properties to develop structure-property correlations. Blending of GMB in HDPE is carried out using a Brabender mixer with processing parameters optimized for minimal filler breakage. Flexural and tensile test specimens are compression molded with 20, 40 and 60 vol% of GMB. Particle fracture increases with increasing GMB content due to increased particle to particle interaction during processing. Additionally, increasing wall thickness makes GMBs stronger and results in reduced particle fracture. Flexural modulus increases while strength decreases with increasing filler content. Tensile strength decreases with increasing filler content, while tensile modulus is relatively unchanged. GMB volume fraction has a more prominent effect than the wall thickness on the mechanical properties of syntactic foams. Specific moduli of GMB/HDPE foams are superior while specific strength is comparable to neat HDPE. © 2017 Elsevier Ltd
DFT Study about the Effect of Doping on the Properties of GaSb Material and Designing of High-Efficiency Infrared Photodetector
(John Wiley and Sons Inc, 2023) Bhandari, B.; Yadav, A.K.; Singh, R.; Kiran, G.; Singh, A.K.; Garg, V.; Pandey, S.K.
The gallium antimonide (GaSb) material has very attractive electronic and optoelectronic properties which are suitable for next-generation infrared (IR) photodetector applications. In this work, properties of undoped GaSb material such as density of states, bandstructure, electron density, absorption coefficient, dielectric function, refractive index, and extinction coefficient are calculated using density-functional theory (DFT). Moreover, the effects of doping with Ge, Sn, and Zn elements on these properties of GaSb material are investigated. It is found that undoped GaSb material exhibits a direct gap of ≈0.72 eV. Among different doping elements, Ge-doped GaSb produces a very significant enhancement in optical properties. The Ge-doped GaSb demonstrates a four times higher absorption coefficient in comparison to undoped GaSb in the IR region at 0.8 eV photon energy. GaSb-based photodetector device is designed using the Solar Cell Capacitance Simulator (SCAPS) 1D tool. The efficiency of the designed photodetector with optimum thicknesses and doping of different layers is found to be improved from 21.34% to 25.91% after incorporating the absorption data set obtained from the DFT calculations. Additionally, the photodetector with optimum parameters demonstrates maximum responsivity of value ≈0.31 A W−1. In the previous findings, it is demonstrated that GaSb is a very suitable material for next-generation IR photodetector applications. © 2023 Wiley-VCH GmbH.
Dielectric response of double layered perovskite Sr3MnTiO7
(2016) Chowki, S.; Sahu, B.; Singh, A.K.; Mohapatra, N.
The results of dielectric and resistivity measurements on the Ruddlesden-Popper (RP) type compound Sr3MnTiO7 (SMTO) is presented here. The dielectric response of the compound was recorded in the temperature range 10-300 K with the probing frequency from 500 Hz-5 MHz. We observe a broad anomaly at ~ 200 K in the temperature dependence of dissipation factor (tan?) and corresponding change in slope in the dielectric constant ?r(T) which may be attributed to a difference in the conduction mechanism below and above 200 K. The overall dielectric dispersion of SMTO resembles to that of the double perovskites Sr2MnTiO6 and La2NiMnO6 which follows the modified Debye relaxation equation. This indicates a relaxor type dielectric behavior of SMTO may be due to the contribution of grain boundary effects. � 2016 Author(s).
Experimental analysis of Android malware detection based on combinations of permissions and API-calls
(Springer-Verlag France 22, Rue de Palestro Paris 75002, 2019) Singh, A.K.; Jaidhar, C.D.; M.a, M.A.A.
Android-based smartphones are gaining popularity, due to its cost efficiency and various applications. These smartphones provide the full experience of a computing device to its user, and usually ends up being used as a personal computer. Since the Android operating system is open-source software, many contributors are adding to its development to make the interface more attractive and tweaking the performance. In order to gain more popularity, many refined versions are being offered to customers, whose feedback will enable it to be made even more powerful and user-friendly. However, this has attracted many malicious code-writers to gain anonymous access to the user’s private data. Moreover, the malware causes an increase of resource consumption. To prevent this, various techniques are currently being used that include static analysis-based detection and dynamic analysis-based detection. But, due to the enhancement in Android malware code-writing techniques, some of these techniques are getting overwhelmed. Therefore, there is a need for an effective Android malware detection approach for which experimental studies were conducted in the present work using the static features of the Android applications such as Standard Permissions with Application Programming Interface (API) calls, Non-standard Permissions with API-calls, API-calls with Standard and Nonstandard Permissions. To select the prominent features, Feature Selection Techniques (FSTs) such as the BI-Normal Separation (BNS), Mutual Information (MI), Relevancy Score (RS), and the Kullback-Leibler (KL) were employed and their effectiveness was measured using the Linear-Support Vector Machine (L-SVM) classifier. It was observed that this classifier achieved Android malware detection accuracy of 99.6% for the combined features as recommended by the BI-Normal Separation FST. © 2019, Springer-Verlag France SAS, part of Springer Nature.
Experimental investigation of torsional vibration isolation using Magneto Rheological Elastomer
(2018) Praveen, Shenoy, K.; Singh, A.K.; Sai, Aditya, Raman, K.; Gangadharan, K.V.
Rotating systems suffer from lateral and torsional vibrations which have detrimental effect on the roto-dynamic performance. Many available technologies such as vibration isolators and vibration absorbers deal with the torsional vibrations to a certain extent, however passive isolators and absorbers find less application when the input conditions are dynamic. The present work discusses use of a smart material called as Magneto Rheological Elastomer (MRE), whose properties can be changed based on magnetic field input, as a potential isolator for torsional vibrations under dynamic loading conditions. Carbonyl Iron Particles (CIP) of average size 5 ?m were mixed with RTV Silicone rubber to form the MRE. The effect of magnetic field on the system parameters was comprehended under impulse loading conditions using a custom built in-house system. Series arrangement of accelerometers were used to differentiate between the torsional and the bending modes of vibration of the system. Impact hammer tests were carried out on the torsional system to study its response, in the presence and absence of magnetic field. The tests revealed a shift in torsional frequency in the presence of magnetic field which elucidates the ability of MRE to work as a potential vibration isolator for torsional systems. � The Authors, published by EDP Sciences, 2018.
Experimental investigation of torsional vibration isolation using Magneto Rheological Elastomer
(EDP Sciences edps@edpsciences.com, 2018) Shenoy, K.; Singh, A.K.; Sai Aditya Raman, K.; Gangadharan, K.V.
Rotating systems suffer from lateral and torsional vibrations which have detrimental effect on the roto-dynamic performance. Many available technologies such as vibration isolators and vibration absorbers deal with the torsional vibrations to a certain extent, however passive isolators and absorbers find less application when the input conditions are dynamic. The present work discusses use of a smart material called as Magneto Rheological Elastomer (MRE), whose properties can be changed based on magnetic field input, as a potential isolator for torsional vibrations under dynamic loading conditions. Carbonyl Iron Particles (CIP) of average size 5 Î¼m were mixed with RTV Silicone rubber to form the MRE. The effect of magnetic field on the system parameters was comprehended under impulse loading conditions using a custom built in-house system. Series arrangement of accelerometers were used to differentiate between the torsional and the bending modes of vibration of the system. Impact hammer tests were carried out on the torsional system to study its response, in the presence and absence of magnetic field. The tests revealed a shift in torsional frequency in the presence of magnetic field which elucidates the ability of MRE to work as a potential vibration isolator for torsional systems. Â© The Authors, published by EDP Sciences, 2018.
Five-Level Switched Capacitor Inverter for Photovoltaic Applications
(Taylor and Francis Ltd., 2022) Singh, A.K.; Mandal, R.K.; Raushan, R.; Anand, R.
This paper proposes a switched-capacitor based single-phase five-level inverter configuration that operates under boost operation and generates a voltage that is more than the DC source voltage. The proposed five-level inverter uses a capacitor and boots the output voltage. In this proposed inverter, capacitor gets charged in parallel while it discharges in series connections so that output voltage may attain higher magnitude than the DC source voltage. Sinusoidal Pulse Width Modulation-based techniques are considered to produce the required gate pulses for operating the switching devices of the inverter. The five-level switched-capacitor inverter is combined with the PV system via DC–DC boost converters to extract the maximum power using MPPT algorithm. To verify its capability, the PV-based system is further integrated to the utility grid. The operation and performance of the suggested switched-capacitor inverter coupled with the grid-connected PV system are also analyzed by developing its model in MATLAB/Simulink environment. © 2022 IETE.
Growth optimization and DFT investigation of doping effect on properties of VS2 monolayer crystals
(Springer Science and Business Media Deutschland GmbH, 2023) Yadav, A.K.; Patel, C.; Kiran, G.; Singh, R.; Singh, A.K.; Garg, V.; Mukherjee, S.; Pandey, S.K.
The vanadium disulfide (VS2) material, a prominent member of the two-dimensional materials family, has great potential to bridge the performance gap between current performance and contemporary energy storage device needs. Here, we report the optimization of the growth temperature of VS2 monolayer crystals using a chemical vapor deposition system. It is also found the crystal size increases with the increase of growth temperature up to 770 °C. Further increasing of growth temperature resulted in a reduction of crystal size. The atomic force microscopy measurement demonstrated the growth of monolayer thick VS2 crystal. Raman spectra revealed the formation of H-phase monolayer high-quality VS2 crystals. To understand the precise impact of doping on electronic properties, the substitutional doping of VS2 monolayer with chromium, molybdenum, and tungsten was also examined using density functional theory. The VS2 monolayer exhibits an indirect energy band gap that decreases after chromium doping of the VS2 lattice and vanishes after molybdenum and tungsten doping. Finally, it is found that tungsten-doped VS2 monolayer exhibits strong metallic character and other exceptional properties, making it suitable for electrodes of various energy storage devices. Graphical abstract: [Figure not available: see fulltext.]. © 2023, The Author(s), under exclusive licence to EDP Sciences, SIF and Springer-Verlag GmbH Germany, part of Springer Nature.
In silico structural and functional analysis of bacillus uricases
(Bentham Science Publishers, 2021) Nelapati, A.K.; Meena, S.; Singh, A.K.; Bhakta, N.; JagadeeshBabu, P.E.
Background: Excluding humans, the peroxisomal uricase is responsible for the catabolism of uric acid into allantoin in many species like microorganisms, plants, and inverte-brates. Particularly in humans, the synthesis and excretion of uric acid are naturally balanced. When the uric acid concentration crosses 7 mg/dl, it results in conditions such as hyperuricemia and gout. Uricase is one of the potential sources for the reduction of uric acid in humans. Uricase is also widely used as a commercial diagnostic reagent in medical and clinical biochemistry to esti-mate the uric acid concentration in blood and other biological fluids. Computational approaches can be used for screening and investigation of uricase enzyme with desirable characteristics that can be employed in diverse industrial applications. Objectives: The present study deals with computational-based structural, functional, and phylogenetic analyses of uricase enzymes from various Bacillus species. Methods: Seventy uricase protein sequences from Bacillus species were selected for multiple sequence alignment, phylogenetic analysis, motif assessment, domain architecture examination, understanding of basic physicochemical properties and in silico identification of the composition of amino acids in uricase. Further, structural (secondary and tertiary structure prediction), and functional (CYS_REC, MOTIF scan, CD-search, STRING, SOSUI, and PeptideCutter) analyses of uric-ase were performed. Results: Bacillus simplex (WP_063232385.1) was chosen as the representative species of the Bacillus genera. The three-dimensional (3D) structure of B. simplex uricase was predicted and validated using QMEAN, RAMPAGE, ERRAT, Verify 3D and PROQ servers. The analysis revealed that the tertiary structure of the selected uricase has good quality and acceptability. Conclusion: Computational analysis of uricase from various Bacillus sources revealed that all the selected Bacillus uricases are active within acidic to a neutral environment, and thermally stable with a molecular weight ranging from 35.59-59.85kDa. The secondary structure analysis showed that all uricases are rich in alpha-helices and sheets. The CDD tool identified two conserved do-mains, one of which belongs to OHCU decarboxylase and another belongs to Uricase superfamily. The quality estimation of 3D modeled protein gave a high overall quality factor score of 94.64. Al-so, all Bacillus species of uricase enzyme and their corresponding genes showed a strong correlation from the phylogenetic comparison of the selected taxa. The present detailed computational investigation on the uricase protein could help in screening a suitable uricase producing microbe with desirable characteristics for industrial application. © 2021 Bentham Science Publishers.
Microstructure and corrosion behavior of laser processed NiTi alloy
(Elsevier Ltd, 2015) Marattukalam, J.J.; Singh, A.K.; Datta, S.; Das, M.; Balla, V.K.; Bontha, S.; Kalpathy, S.K.
Abstract Laser Engineered Net Shaping (LENS™), a commercially available additive manufacturing technology, has been used to fabricate dense equiatomic NiTi alloy components. The primary aim of this work is to study the effect of laser power and scan speed on microstructure, phase constituents, hardness and corrosion behavior of laser processed NiTi alloy. The results showed retention of large amount of high-temperature austenite phase at room temperature due to high cooling rates associated with laser processing. The high amount of austenite in these samples increased the hardness. The grain size and corrosion resistance were found to increase with laser power. The surface energy of NiTi alloy, calculated using contact angles, decreased from 61 mN/m to 56 mN/m with increase in laser energy density from 20 J/mm2 to 80 J/mm2. The decrease in surface energy shifted the corrosion potentials to nobler direction and decreased the corrosion current. Under present experimental conditions the laser power found to have strong influence on microstructure, phase constituents and corrosion resistance of NiTi alloy. © 2015 Elsevier B.V.
[No abstract available]
(Springer Netherlands, Low cycle fatigue behavior of an (? + ?) titanium alloy) Nanjundaswamy, G.S.; Ramachandra, C.; Sengupta, P.K.; Chatterji, B.; Sudhakara Nayak, H.V.; Singh, A.K.
1998
Performance Analysis of PV Module Using Pyramid Surface Texturing Approach
(Springer Science and Business Media Deutschland GmbH, 2022) Bansal, R.K.; Singh, S.; Singh, A.K.; Waseem Ahmad, M.
Performance analysis of thin-film solar modules has been done using the pyramid texturing technique. To change the geometry of the surface of the solar cell through surface texturing technique, it increases the effective area of thin-film module. Significant improvement has been found by inserting a random pyramid structure. TCAD and PvSyst software is used to design and development of surface texturing and temperature-dependent loss minimization. Efficiency improvement of 3% has been achieved using this noble approach. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
Performance of magnetorheological elastomer based torsional vibration isolation system for dynamic loading conditions; ??????????????????????????
(Central South University of Technology f-ysxb@mail.csut.edu.cn, 2020) Shenoy, S.K.; Kuchibhatla, S.A.R.; Singh, A.K.; Gangadharan, K.V.
Vibration isolation is an effective method to mitigate unwanted disturbances arising from dynamic loading conditions. With smart materials as suitable substitutes, the conventional passive isolators have attained attributes of semi-active as well as the active control system. In the present study, the non-homogenous field-dependent isolation capabilities of the magnetorheological elastomer are explored under torsional vibrations. Torsional natural frequency was measured using the serial arrangement of accelerometers. Novel methods are introduced to evaluate the torsional stiffness variations of the isolator for a semi-definite and a motor-coupled rotor system. For the semi-definite system, the isolation effect was studied using the frequency response functions from the modal analysis. The speed-dependent variations for motor-coupled rotor system were assessed using the shift in frequency amplitudes from torque transducers. Finite element method magnetics was used to study the variations in the non-homogenous magnetic field across the elastomer. The response functions for the semi-definite rotor system reveal a shift in the frequency in the effect of the magnetic field. Speed-dependent variations in the frequency domain indicate an increment of 9% in the resonant frequency of the system. © 2020, Central South University Press and Springer-Verlag GmbH Germany, part of Springer Nature.