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A bioinspired optimization strategy: to minimize the travel segment of the nozzle to accelerate the fused deposition modeling process

Sridhar Sundarraj, Aditya K., Venkatraman Ramamoorthi, Venkatesan M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 4

art. no. e146236

EN

The fused deposition modeling process of digital printing uses a layer-by-layer approach to form a three-dimensional structure. Digital printing takes more time to fabricate a 3D model, and the speed varies depending on the type of 3D printer, material, geometric complexity, and process parameters. A shorter path for the extruder can speed up the printing process. However, the time taken for the extruder during printing (deposition) cannot be reduced, but the time taken for the extruder travel (idle move) can be reduced. In this study, the idle travel of the nozzle is optimized using a bioinspired technique called "ant colony optimization" (ACO) by reducing the travel transitions. The ACO algorithm determines the shortest path of the nozzle to reduce travel and generates the tool paths as G-codes. The proposed method’s G-code is implemented and compared with the G-code generated by the commercial slicer, Cura, in terms of build time. Experiments corroborate this finding: the G-code generated by the ACO algorithm accelerates the FDM process by reducing the travel movements of the nozzle, hence reducing the part build time (printing time) and increasing the strength of the printed object.

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Hydrous Methanol Fuelled HCCI Engine Using Ignition Improver CAI Method - ANN Approach

Venkatesan M., Moorthi N. S. V., Franco P. A., Manivannan A., Karthikeyan R.

Mechanics and Mechanical Engineering

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2015

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Vol. 19, nr 1

31--49

EN

The present study is to examine the performance and emission characteristics of a Homogeneous Charge Compression Ignition (HCCI) engine where hydrous methanol (85% methanol and 15% water) is used as primary fuel and Diethyl ether (DEE) as an ignition improver. A modified diesel engine has been used as a HCCI engine. By measuring the excess air ratio (λDEE), the quantity of DEE flow rate is measured and excess air ratio (fiDEE) is varied from fiDEE5.6 to fiDEE 9.5. Experimental results reveal that HCCI engine gives better brake thermal efficiency (BTE) at high loads (λDEE 9.5). It shows decrease in oxides of nitrogen (NOx) emission, slightly high emission of carbon monoxide (CO) and unburned hydrocarbon (HC) compared to conventional compression ignition (CI) engine. Radial basis function neural network (RBFN) model has been developed with brake power, excess air ratio and energy share as input and BTE, CO, HC, NOx, rate of pressure rise as output. About 80% of total experimental data is used for training purposes, and 20% is used for testing. The performance of the developed RBFN model were compared with experimental data, and were statistically evaluated which was found to be in good agreement.

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Performance Analysis of Motor Cycle Helmet under Static and Dynamic Loading

Gandhi V. C. S., Kumaravelan R., Ramesh S., Venkatesan M., Ponraj M. R.

Mechanics and Mechanical Engineering

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2014

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Vol. 18, nr 2

85--96

EN

Each year nearly nine hundred persons die in head injuries and over fifty thousand persons are severally injured due to non wearing of helmets . In motor cycle accidents, the human head is exposed to loads exceeding several times the loading capacities of its natural protection. In this work, an attempt has been made for analyzing the helmet with all the standard data. The simulation software ‘ANSYS’ is used to analyze the helmet with different conditions such as bottom fixed-load on top surface, bottom fixed– load on top line, side fixed–load on opposite surface, side fixed–load on opposite line and dynamic analysis. The maximum force of 19.5 kN is applied on the helmet to study the model in static and dynamic conditions. The simulation has been carried out for the static condition for the parameters like total deformation, strain energy, von Mises stress for different cases. The dynamic analysis has been performed for the parameter like total deformation and equivalent elastic strain. The result shows that this values are concentrated in the retention portion of the helmet. These results has been compared with the standard experimental data proposed by the BIS and well within the acceptable limit.