Faculty Publications
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Item Mechanical, Dynamic Mechanical and Vibration Behavior of Nanoclay Dispersed Natural Fiber Hybrid Intra-ply Woven Fabric Composite(Springer Science and Business Media B.V., 2016) RAJESH, M.; Jeyaraj, P.; Nagarajan, N.Influence of nanoclay dispersion on mechanical, dynamic mechanical and free vibration characteristics of basket type intra-ply woven banana/jute (banana yarn-weft direction, jute yarn-warp direction) hybrid polyester composite has been investigated. Results revealed that loading of nanoclay enhances the mechanical properties of the composite significantly as it improves the adhesion between fiber and matrix. Dynamic mechanical analysis result reveals that nanoclay addition significantly increases the storage modulus and glass transition temperature of the intra-ply hybrid composite. From free vibration studies, carried out on laminated beam like structures, it is found that the natural frequency of the composite laminate increases till 2 wt% of nanoclay while the modal damping increases when the wt% of nanoclay is more than 2. However, due to the agglomeration effect of nanoclay the properties are not improved for nanoclay loading beyond 2 wt%. © 2016, Springer Science+Business Media Singapore.Item A study on the factors influencing the load transfer efficiency in concrete block pavements(2012) Thameel, S.S.; Amar Kumar, D.S.N.V.; Pancharathi, P.Concrete Block Pavements (CBP) are essentially precast blocks arranged in a specific pattern over a sub base and interlocked with graded bedding and jointing sand. The block size and shape, joint gap and joint filling sand size and laying pattern influence the effectiveness of the interlocking or the distribution of wheel loads. The measure of effectiveness - Load Transfer Efficiency (LTE), is the ratio of deflection between a loaded block to an adjacent unloaded block. In the present LTE study, joint filling sand of three particle sizes (1.18, 0.6 and 0.3mm), laying patterns of two types [stretcher and basket weave), concrete mixes with four variations (cement, cement with 20% fly ash, cement with steel fibre (0.5%) and cement with both fly ash and steel fibre] were tested. The test section consisted of 100 mm x 200 mm x 100mm blocks fixed over a 20 mm thick bed of 4.75 mm sand. A wet mix macadam layer over the sub grade supported the blocks. The study revealed that the joint filling with 0.6 mm sand gave a higher LTE than the other two sizes. The basket weave resulted in a higher average LTE than the stretcher bond and incorporating steel fibre and fly ash in concrete also showed an increase in the LTE.Item Synthesis and performance characterization of PS-PPEES nanoporous membranes with nonwoven porous support(2013) Hegde, C.; Isloor, A.M.; Padaki, M.; Fun, H.-K.The present work describes about the synthesis and characterization of Polysulfone blend nanoporous membrane with nonwoven support. This Nonwoven support provides mechanical strength to membrane while filtration process and minimizes membrane fouling. Hence it helps in better membrane performance in terms of salt rejection, improved flux, thermal stability and fairly increases in proton conductivity. In this work we have used K.C.270 nonwoven material consisting of fine polyester fibers and has a thickness of below 110. ?m. © 2011.Item Communication and computation optimization of concurrent kernels using kernel coalesce on a GPU(John Wiley and Sons Ltd, 2015) Bayyapu, B.; Guddeti, R.M.R.; Raghavendra, P.S.General purpose computation on graphics processing unit (GPU) is rapidly entering into various scientific and engineering fields. Many applications are being ported onto GPUs for better performance. Various optimizations, frameworks, and tools are being developed for effective programming of GPU. As part of communication and computation optimizations for GPUs, this paper proposes and implements an optimization method called as kernel coalesce that further enhances GPU performance and also optimizes CPU to GPU communication time. With kernel coalesce methods, proposed in this paper, the kernel launch overheads are reduced by coalescing the concurrent kernels and data transfers are reduced incase of intermediate data generated and used among kernels. Computation optimization on a device (GPU) is performed by optimizing the number of blocks and threads launched by tuning it to the architecture. Block level kernel coalesce method resulted in prominent performance improvement on a device without the support for concurrent kernels. Thread level kernel coalesce method is better than block level kernel coalesce method when the design of a grid structure (i.e., number of blocks and threads) is not optimal to the device architecture that leads to underutilization of the device resources. Both the methods perform similar when the number of threads per block is approximately the same in different kernels, and the total number of threads across blocks fills the streaming multiprocessor (SM) capacity of the device. Thread multi-clock cycle coalesce method can be chosen if the programmer wants to coalesce more than two concurrent kernels that together or individually exceed the thread capacity of the device. If the kernels have light weight thread computations, multi clock cycle kernel coalesce method gives better performance than thread and block level kernel coalesce methods. If the kernels to be coalesced are a combination of compute intensive and memory intensive kernels, warp interleaving gives higher device occupancy and improves the performance. Multi clock cycle kernel coalesce method for micro-benchmark1 considered in this paper resulted in 10-40% and 80-92% improvement compared with separate kernel launch, without and with shared input and intermediate data among the kernels, respectively, on a Fermi architecture device, that is, GTX 470. A nearest neighbor (NN) kernel from Rodinia benchmark is coalesced to itself using thread level kernel coalesce method and warp interleaving giving 131.9% and 152.3% improvement compared with separate kernel launch and 39.5% and 36.8% improvement compared with block level kernel coalesce method, respectively. © 2014 John Wiley & Sons, Ltd.Item Dynamic mechanical analysis and free vibration behavior of intra-ply woven natural fiber hybrid polymer composite(SAGE Publications Ltd info@sagepub.co.uk, 2016) RAJESH, M.; Jeyaraj, P.Influence of nature of weaving pattern and intra-ply hybridization of natural fibers on dynamic mechanical and free vibration characteristics of woven banana/jute polyester composite has been investigated. Results revealed that basket-type composite has better dynamic properties due to uniform stress distribution in both warp and weft directions. Warp jute fiber and weft banana fiber (WJWB) and both warp and weft banana and jute fiber (WAWBJ) intra-ply hybrid composites have better dynamic mechanical behavior as relatively stronger fiber is oriented along the loading direction. Experimental modal analysis carried out on beam-like samples revealed that warp and weft banana and jute fiber intra-ply hybrid composite has better natural frequencies while huckaback woven and warp banana fiber and weft jute fiber composites have better modal damping factors. © The Author(s) 2015.Item Mechanical Properties of Natural Fiber Braided Yarn Woven Composite: Comparison with Conventional Yarn Woven Composite(Science Press bcanji@mail.sioc.ac.cn, 2017) RAJESH, M.; Jeyaraj, J.The effect of reinforcing natural fiber in the form of braided yarn woven fabric on mechanical properties of polymer composite was investigated. The results of braided yarn fabric composites were compared with the conventional yarn fabric composite and random oriented intimately mixed short fiber composites for the same percentage of fiber weight. The effect of intra-ply hybridization, by keeping two different natural fiber yarns along two different directions of a woven fabric, on mechanical properties of the woven fabric composite was also analyzed. Natural fiber braided yarn fabric reinforcement significantly increased the mechanical properties of the composites compared with that of the conventional woven fabric and short fiber reinforcements. Intra-ply hybridization of two different natural fibers improved the mechanical properties of the conventional woven fabric composite while it could not enhance the properties of the braided fabric composite. The improvement in impact property is very high compared to tensile and flexural properties due to the braided yarn fabric reinforcement. © 2017 Jilin UniversityItem Experimental investigation on buckling and free vibration behavior of woven natural fiber fabric composite under axial compression(Elsevier Ltd, 2017) RAJESH, M.; Jeyaraj, J.Influence of axial compression load on buckling and free vibration characteristics of natural fiber fabric polymer composite beam is analyzed experimentally. Critical buckling strength, free vibration frequencies and modal loss factors are obtained and analyzed. It is found that buckling strength increases with number of layers of fabric in composite. It is also observed that weaving pattern of the fabric influences buckling strength of the composite and basket type woven fabric enhances the buckling strength compared to plain and herringbone woven fabric composites. Sandwich composites with glass fiber fabric facing layer and natural fiber fabric as core layer having higher buckling strength. Free vibration frequency reduces with increase in axial compression load while modal damping factor increases in the pre-buckling region. However, this behavior reverses in the post-buckling region. The load-deflection obtained experimentally is compared with finite element result obtained considering the geometric non-linearity. © 2016 Elsevier LtdItem Mechanical and dynamic mechanical behaviour of novel glass–natural fibre intra-ply woven polyester composites(Springer India sanjiv.goswami@springer.co.in, 2017) RAJESH, M.; Jeyaraj, J.A novel intra-ply woven fabric polyester composite with glass fibre yarns in one direction and natural fibre yarns in another direction of basket-type woven fabric has been investigated for mechanical and dynamic mechanical characteristics. Individual glass fibre woven fabric, natural fibres woven fabric and intra-ply natural fibres woven fabric composites are also investigated for the comparison purpose. Results reveal that the intra-ply woven fabric hybridization enhances impact and damping properties of the composite significantly than the tensile and flexural properties. Intra-ply woven fabrics with glass fibre yarns in warp direction and jute fibre yarns in weft direction (WGWJ) exhibit better impact properties compared with woven fabric with other combinations. Dynamic mechanical analysis results reveal that intra-ply woven fabric composite with glass fibre yarns in warp direction and jute and banana fibre yarns in weft direction (WGWJAB) gives higher damping characteristics due to the multi-level interaction between fibre–fibre and fibre–matrix interactions. © 2017, Indian Academy of Sciences.Item Mechanical characterization of natural fiber intra-ply fabric polymer composites: Influence of chemical modifications(SAGE Publications Ltd info@sagepub.co.uk, 2017) RAJESH, M.; Jeyaraj, P.The influence of surface treatment (alkali, potassium permanganate, benzoyl chloride and silane) on the mechanical, dynamic mechanical and free vibration properties of intra-ply hybrid banana/jute woven fabric composite has been analyzed. Intra-ply woven fabrics are fabricated by keeping banana yarn in weft direction and jute yarn in warp direction of a basket-type woven fabric. Results reveal that the enhancement of tensile and flexural strengths of the composite due to the chemical treatment is marginal, except for the benzoyl chloride treatment. However, the chemical treatment results in better impact strength compared to the untreated composite. Tensile, flexural and impact strengths of the benzoyl chloride treatment increase by 10%, 30% and 50%, respectively, compared to untreated composite. It is evident from Fourier Transform-Infrared Spectra that benzoyl chloride treatment effectively removes the hemicellulose and lignin content. It is observed that benzoyl chloride and alkali treatment improves the dynamic mechanical characteristics. Experimental modal analysis carried out on intra-ply fabric composites reveals that benzoyl chloride treatment increases the natural frequency significantly compared to the untreated composite. © 2017, © The Author(s) 2017.Item Mechanical behavior of woven natural fiber fabric composites: Effect of weaving architecture, intra-ply hybridization and stacking sequence of fabrics(SAGE Publications Ltd info@sagepub.co.uk, 2018) RAJESH, M.; Singh, S.P.; Jeyaraj, P.A comprehensive analysis carried out on the mechanical and free vibration properties of woven natural fiber polymer composites is presented. Jute fabric with three different weave types (plain, basket and herringbone) and intra-ply woven jute-banana fabrics are considered for investigation of the effect of weave type of a fabric and its stacking sequence on mechanical, dynamic mechanical and free vibration properties. Enhancement of the properties is found with the number of layers of fabric and better properties obtained for four layers. Uniform stress distribution along warp and weft direction of fabric with basket weave type lead to better properties compared to other weave types for four-layered composites. Intra-ply hybridization of jute-banana also enhances the mechanical properties but slightly less than the jute-basket fabric composite. The investigations on effect of layer sequence of fabrics revealed improvement in mechanical properties. Layered composite with relatively strong intra-ply fabric as the facing layer and relatively weak jute plain fabrics as the core layer has higher tensile and flexural properties. Experimental modal analysis carried out on beam-like composite laminates reveal that natural frequencies and associated modal damping factor are significantly influenced by stacking sequence and weave type of a fabric. The density of the composite calculated based on Archimedes principle matches well with the theoretical values. © 2016, © The Author(s) 2016.