ANN MODELLING OF SMALL HOLE DRILLING ON MONEL METAL BY USING ELECTRICAL DISCHARGE MACHINING

The selection of best combination of the process parameters in small hole drilling by Electrical Discharge Machining for an optimum material removal rate with a reduced tool wear rate can reduce machining time and yield better performances. Artificial Neural Network (ANN) has emerged as a powerful tool for modelling complex processes is used for achieving better performance parameter. Artificial Neural Network (ANN) with back propagation algorithm have been used for optimizing and modelling process. The experiments have been designed according to Taguchi L9 orthogonal array. The input parameters were considered for conducting experimentation are namely Discharge Current, Pulse off time and Pulse on time respectively. The performance measures were Material Removal Rate (MRR) and Tool Wear Rate (TWR). ANN models have been developed with varying number of neurons in the hidden layer from 5 to 10. It was found that one hidden layer with 9 neurons predicted the best results. The predicted values were compared with actual experimental results and the predicted values were almost equal to the expected with very less error.Â

Experimental investigations on Thermal Performance of Copper with Aluminium Based Finned Heat sinks for Electronics Cooling System

An Experimental investigation on the thermal performance of copper with aluminium based finned heat sinks for electronics cooling system was studied. The heat sinks have different material proportions containing major constituent of aluminium and minor constituent of copper. Considered with straight finned heat sink for the experiments for its easiness in fabrication and efficient heat transfer properties. The observational results for aluminium with copper alloy are compared with pure aluminium heat sink.  Heat sink geometry, fin pitch and its height were taken from the commercially available heat sinks. In this research work best heat sink geometry is chosen and cooked up with different volume of copper added with aluminium. Selected four different spots of heat sinks and the temperature raising characteristics were measured for natural convection. also the temperature is raised to a fixed temperature and the temperature lowering characteristics were measured in forced convection as the air circulation takes more heat to keep the heat sink temperature within the desired level

Decision Making Methodology for Heat Sink Material Selection Using a Compromise Ranking and Outranking Method under Fuzzy Environment

This paper proposes judicious selection of heat sink materials by extensive evaluation under consideration of numerous alternative materials and evaluation criteria. This enhances the reliability and life of modern electronic devices. Thermal management of electronic devices relies on stabilizing the component temperature at an acceptable level. A hierarchical decision making framework structure based on novel hybrid fuzzy set theory combined with multi-criteria decision-making (MCDM) model is formed. A fuzzy analytic hierarchical process (FAHP) is more realistic to use linguistic terms to describe the expectation value, perception value and important weight of evaluation criteria. This study comprises six alternatives and seven criteria such as thermal conductivity, density, specific heat, melting point, latent heat of fusion, thermal expansion and cost. The results obtained from FAHP-TOPSIS and FAHP- VIKOR is compared with each other. These results help the designer to choose the apt heat sink material for designing and developing electronic packages

MAINTENANCE STRATEGY EVALUATION BASED ON AHP – TOPSIS

This paper presents an application of Analytical Hierarchy Process (AHP) is combined with Technique for Order Preference by Similarly to Ideal Solution (TOPSIS) model for selection of the best maintenance strategy for pump in paper industry. AHP is used to compute the criteria weights whereas TOPSIS is used to ranking the maintenance strategy alternatives. This study focuses on four maintenance strategies such as Corrective Maintenance (CM), Predictive maintenance (PM), Time based preventive Maintenance (TM) & Condition Based Maintenance (CBM) and four main criteria such as safety, cost, added value and feasibility are used to evaluate the optimum maintenance strategy

Durability, Lube Oil Contamination and a Ferrography Study on a Diesel Engine Fuelled with Distilled Tyre Oil

This research work focuses on durability tests on diesel engines powered by 30 vol% distilled tyre oil with diesel (DTPO30). The duration of the study was for 1500 running hours and includes an analysis of engine performance, emission formation, viscosity, wear, and additives in lubrication oil with a ferrographic examination. The respective wear and additives in the oil were measured every 450 hours. In the engine running on DTPO30, brake thermal efficiency (BTE) declined by up to 0.5% and brake specific fuel consumption (BSFC) also diminished by up to 1.5% after 1500 hours when compared with the initial stage operation. In addition, all the harmful emission parameters such as NOx, CO, and HC grew by between 0.7 % and 1.1%. The viscosity of lube oil was observed to fall by up to 13% with diesel and 36% with DTPO30 compared with the initial condition. The amount of additives was also lower in the lubrication oil in DTPO30 compared with in pure diesel. A higher carbon deposition was also found in many places, such as in the piston top, around the injector nozzle, and in the valve seat with DTPO30. The wear of each part was identified by estimating the metal contamination in the lube oil by means of a ferrography tester. Further, the metal contaminations in the lube oil were found to amount to as high as 79% in DTPO30. In addition, the size of the particles was identified to be larger than in the case of diesel

Decentralised green power generation using methyl esters of non-edible oils

Istraživački radovi o sustavima obnovljivih izvora energije za elektrifikaciju sela vrlo su intenzivni posljednjih godina. U udaljenim područjima neka su sela još uvijek izvan dosega električne energije jer je nemoguće povezivanje mrežnog sustava. U svijetu oko dvadeset posto svjetske populacije živi bez struje. Za poboljšanje ruralnog življenja, uporaba zelenih izvora energije obuhvaća veću mogućnost zapošljavanja, energetsku sigurnost i smanjenje učinaka staklenika. Konvencionalna metoda lokalne proizvodnje koristi dizel generator koji nije prihvatljiv za okoliš. Biogoriva su optimistični izbor za ispunjavanje ovog zahtjeva. Biodizel je obnovljivi izvor koji ima gotovo jednaku učinkovitost kao i konvencionalni petrodizel. Ovaj rad pokusno istražuje mješavine biodizela (dizel + biodizel) dobivene od nejestivih ulja kao alternativni izvor energije za pogon dizelskog generatora. U ovoj studiji se uzima u obzir sedam metilnih estera ekstrahiranih iz nejestivih ulja pongamije (indijske breze), jatrobe (jatrophe), mahuae, mesua ferrae (nageškara), sjemenki lana, neema (nim drveta) i sjemenki pamuka. Performanse generatora kao što su regulacija napona, frekvencija, potrošnja goriva, učinkovitost i emisijske značajke nalaze se u različitim uvjetima opterećenja. Na temelju opažanja, nađeno je da je ulje pongamije dobro alternativno gorivo za proizvodnju električne energije.Research work on renewable energy systems for rural electrification have been quite intensive in recent years. In remote areas, some villages are still not reach of electricity because providing grid connection is impossible. Approximately twenty percent of global population are living without electricity in the world. For enhancement of rural livelihood, use of green energy sources encompasses greater employment opportunity, energy security and minimizes the greenhouse effects. The conventional method of local generation uses diesel generator that is not environment friendly. Bio-fuels have been the optimistic choice to meet this requirement. Biodiesel is a renewable source which has nearly the same efficiency as conventional petro-diesel. This paper experimentally investigates biodiesel blends (Diesel+Biodiesel) derived from non-edible oils as an alternative energy source for operating the diesel power generator. In this study, seven methyl esters extracted from non-edible oils of pongamia, jatroba, mahua, mesuaferra, linseed, neem and cotton seed are considered. The generator performances such as voltage regulation, frequency, fuel consumption, efficiency and emission characteristics are found in various load conditions. Based on the observations, pongamia oil was found to be a good alternative fuel for power generation

A fuzzy based hybrid multi criteria decision making methodology for phase change material selection in electronics cooling system

The phase change material (PCM) selection plays a vital role in successful designing of electronic cooling systems. Since large numbers of competitive materials are available today, with each having its own characteristics, applications, advantages, and limitations, the decision for selecting a suitable PCM involves several evaluation criteria. In this article, a novel hybrid multi criteria decision making (MCDM) model is proposed for evaluating a suitable PCM for thermal management systems. The decision model consists of 10 alternative materials with eight evaluation criteria. The Fuzzy Analytical Hierarchy Process (FAHP) - integrated with Technique for Order Preference by Similarity to Ideal Solution (TOPSIS), VlseKriterijumska Optimizacija I KompromisnoResenje (VIKOR) and Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEE) are proposed and applied in the numerical example. The results obtained from FAHP-TOPSIS, FAHP-VIKOR and FAHP- PROMETHEE are compared. The results show that RT-80 is the apt material for thermal management of power electronic devices. Keywords: Multi criteria decision making, Phase change material, Thermal management system, Electronic cooling system