Experimental and numerical evaluation of friction stir welds of AA6061-T6 aluminium alloy

P. Prasanna, B. Subba Rao, G. Krishna Mohana Rao and Anjaneya Prasad

Friction stir welding is a relatively new joining process, which involves the joining of metals without fusion or filler materials. The amount of the heat conducted into the work piece dictates a successful process which is defined by the quality, shape and microstructure of the processed zone, as well as the residual stress and the distortion of the work piece. The amount of the heat gone to the tool dictates the life of the tool and the capability of the tool to produce a good processed zone. Hence, understanding the heat transfer aspect of the friction stir welding is extremely important for improving the process. Many research works were carried out to simulate the friction stir welding using various soft wares to determine the temperature distribution for a given set of welding conditions. Very few attempted to determine the maximum temperature by varying the input parameters using ANSYS. The objective of this research is to develop a finite element simulation of friction stir welding of AA6061-T6 Aluminium alloy. Trend line equations are developed for Thermal conductivity, specific heat and density to know the relationship of these factors with peak temperature. Tensile and hardness values for the welded specimens are found for different rotational speed and feed. Variation of temperature with input parameters is also observed. The simulation model is tested with experimental results. The results of the simulation are in good agreement with that of experimental results.

Removal of cod of reactive dyes using polyaluminium chloride

D. V. Satyanarayana Moorthy and G. Reddy Babu

Textile manufacturing units involved in finishing processes are profuse water consumers. The effluents from these plants are major source of water pollution. Poly Aluminium Chloride (AlCl₃ 6H₂O) is used as a coagulant for the removal of Chemical Oxygen Demand (COD) of selective reactive dyes, which are used for cotton yarn dyeing, at different doses. The results indicate that the removal of COD of various dyes RB41, RB209, RB204 and RB184 are 68, 40, 36, and 29 percent respectively at their optimum doses. The optimum doses of Poly Aluminium Chloride (PAC) for RB41, RB209, RB204 and RB 184 are 5.2, 34.3, 20 and 22mg of PAC per mg. of COD removed, respectively.

Application of response surface methodology on surface roughness in grinding of aerospace materials (6061Al-15vol%SiC_25p)

Dayananda Pai, Shrikantha Rao, Raviraj Shetty and Rajesh Nayak

In this paper, the effects and the optimization of machining parameters on surface roughness in the cylindrical grinding of 6061Al-SiC_25P (MMCs) are investigated. In the grinding process, a machining parameter, such as hardness, flow rate and depth of cut were chosen for evaluation by the response surface methodology. By response surface methodology, a complete realization of the process parameters and their effects were achieved. The variation of surface roughness with machining parameters was mathematically modeled using response surface methodology. Finally, experimentation was carried out to identify the effectiveness of the proposed method.

Experimental investigation into rheological property of copper oxide nanoparticles suspended in propylene glycol- water based fluids

M. T. Naik, G. Ranga Janardhana, K. Vijaya Kumar Reddy and B. Subba Reddy

Nanofluids are a new generation heat transfer fluids and have opened a new horizon in the areas of heat transfer applications. Nanofluids are prepared by dispersing nano-sized metallic particles in conventional fluids of heat transfer. Heat transfer performance of nanofluid depends primarily on its thermo physical properties like viscosity, thermal conductivity, specific heat and desity. Viscosity assumes importance as it affects the pressure drop and hence the pumping power when nano fluids are circulated in a closed loop for transfer of heat in heat exchangers. In the present research, propylene glycol and water (60:40 by weight) is used as base fluid and viscosity of Cuo nanofluid with different particle volume concentration of 0.025, 0.1, 0.4, 0.8 and 1.2 percent is measured. Experimental results thus obtained revealed that temperature and nanoparticle concentration parameters influence the viscosity of nanofluids condiderably. The experimental results obtained in the present experiment found to be in closer agreement with those available in the literature.

The nature and effect of sulphur compounds on Co₂ and air reactivity of petrol coke

Yaw Delali Bensah and Trygve Foosnaes

Abstract:

Three different single-source coke types (SSA, SSB and SSC) were studied for their air and CO₂ reactivities using the Hydro method and the observed correlation with reactivity determinant parameter such as elemental composition was noted. The reaction temperatures were 525 ^oC and 960 ^oC for air and CO₂ reactivities, respectively. Coke sample SSA recorded the highest CO₂ reactivity value of 166 mg/g h while coke sample SSB recorded the lowest value of 25 mg/g h. The coke CO₂ reactivity showed a moderately strong correlation with the combined effect of Na, Fe and Ca concentrations. The inhibitory effect of sulphur as a catalytic poison on Na was observed with significant downward trend in CO₂ reactivity of the investigated cokes. Coke air reactivities showed the expected strong correlation with V. Air reactivity was highest in sample SSC (262 mg/g h) at V concentration of 378 ppm and lowest in sample SSB (39.6 mg/g h) at V concentration of 68 ppm. Sample SSA recorded reactivity value of 129.6 mg/g h at V concentration of 147 ppm. The compound 1-butanethiol was identified by 1-D ¹H NMR and ¹³C NMR, and by 2-D COSY, HSQC and HMBC NMR spectroscopic techniques. It is proposed that 1-butanethiol is one of the possible organosulphur compounds responsible for the reaction with Na forming a stable non-mobile complex partially inhibiting the catalytic effect of Na. 

Evaluation of durability of natural fibre reinforced cement mortar composite- A new approach

G. Ramakrishna, T. Sundararajan and S. Kothandaraman

Abstract:

‘Toughness’ of a composite generally based on the ‘toughness indices’ evaluated by flexural tests as contemplated in several codes (ASTM, ACI, JCI-SF4/JSCE-SF4) may not be appropriate/realistic for natural fibre cement composites containing low modulus fibres like sisal, coir etc., due to several reasons. Further, durability of natural fibre cement composite can be evaluated on the basis of flexural toughness (FT) and it has a special significance. Toughness of a natural fibre composite can also be evaluated by impact tests, which helps in realistic assessment of ductility of the above composite. Evaluation of durability of a natural fibre composite by residual impact strength (I_rs) and flexural toughness index (I_T) and their comparison are presented and discussed. I_rs values could be used to assess the durability of natural fibre composites, than, the conventional ‘toughness indices’ used for composites, in general.

Effect of various parameters on the movement of metallic particles in a single phase gas insulated bus duct with image charges and dielectric coated electrodes

K. B. Madhu Sahu and J. Amarnath

The insulation performance of gas insulated systems (GIS) can be substantially affected by the presence and movement of contaminating metallic particles.  With and without Image charge effect on metallic particle movement in a single phase GIB (Gas Insulated Bus duct) and also with and without dielectric coating on the enclosure is considered in this paper. In the present work the equations describing the motion of the particle due to image charge has been proposed to obtain the particle trajectories. The simulation has been carried out to obtain the particle trajectories at an applied voltage of 132 KV and also the effect of various parameters like radius and length of the Particle, pressure in the bus duct has been examined and presented. Typically a GIB of inner conductor and outer enclosure diameters of 55/155 have been considered for analysis. Different metallic contaminations viz Aluminum and Copper have been considered for the above study.

Analytical study of self-excited vibration on single degree of freedom vibratory-tillage

Soeharsono and Radite PA Setiawan

Abstract:

Analytical and experimental study on vibratory tillage by adding external energy to the tillage tool has been widely conducted. Though this method has been shown to significantly reduce soil resistance, it will, unfortunately, increase the energy consumption excessively. Experimental study on vibratory tillage by self-excited vibration method has also been performed. This method can also reduce soil resistance though not as much as the former. No analytical study of the latter, however, can be found. This paper discusses analytical study of self-excited vibration of tillage-tool on vibratory tillage due to natural excitation of varying cutting forces. The objective of this discussion is to find dynamics parameter of vibratory tillage so the vibration of tillage-tool will be able to reduced draft force required for loosening soil density during tillage operation The Vibration of vibratory tillage was modeled as a vibration with Single Degree of Freedom (SDOF) system. The tillage-tool was connected to an implement by an elliptic spring while the natural excitation of the varying cutting force was modeled as a periodic function, which can be expressed as a Fourier series. The elasticity of elliptic spring and the inertia of tillage tool were optimized such that the tillage-tool vibrates violently around its resonant frequency. This condition decreases both the soils resistance and the draft force required to loosen soil density due to self-exited vibration during tillage operation. The possibility of draft force reduction was investigated further by analyzing time response of the displacement and by analyzing the oscillating pathway of the tine tip.

Comparative analysis of the effect of demulsifiers in the treatment of crude oil emulsion

M. Abdulkadir

Abstract:

This paper is aimed at highlighting the problems of crude oil emulsion and identification of the most effective combination of treatment method through the comparative analysis of various brands of demulsifiers that give the best quality oil. The best quality oil is oil with the lowest Basis sediment and water (BS and W) and low API gravity values. In the process of analysis (bottle test), a combination of factors were used to determine the best treatment condition. They are: Residence time, chemical requirement, heat effect e.t.c. The result of the comparative analysis showed that V44O4 at a temperature of 60°C at a close rate of 50PPM was found most suitable.

Neural network controller (NNC) for a crude oil distillation column

Henri E. Z. Tonnang and A. Olatunbosun

Abstract:

The development of neural network that could be used for the control of an industrial process is discussed. Field data from a working distillation column or fractionator of crude oil refinery in Nigeria was used for the development and testing the effectiveness of the controller. The developed controller performed optimally when compared with the installed distributed control system based on proportional integral and derivative algorithm in the company with well over 95% correlation between the expected data and obtained data.

Performance and emission characteristics of a 4 stroke C.I. engine operated on Honge methyl ester using artificial neural network

Shivakumar, Srinivas Pai P., Shrinivasa Rao B. R. and Samaga B. S.

Abstract:

In wake of the present energy environment crises it has become essential to identify renewable and alternative clean burning fuels. One of the significant routes to tackle the problem of increasing prices and the pollution problems of petroleum fuels is by the use of vegetable oil fuels known as biodiesels. In the present work biodiesel was prepared from Honge oil (Pongamia) and used as a fuel in C.I engine. Performance studies were conducted on a single cylinder four-stroke water-cooled compression ignition engine connected to an eddy current dynamometer. Experiments were conducted for different percentage of blends of Honge oil with diesel at various compression ratios. Experimental investigation on the Performance parameters and Exhaust emissions from the engine were done. Artificial Neural Networks (ANNs) were used to predict the Engine performance and emission characteristics of the engine. To train the network compression ratio, blend percentage, percentage load were used as the input variables where as engine performance parameters together with engine exhaust emissions were used as the output variables. Experimental results were used to train the ANN. Back-propagation algorithm was used to train the network. ANN results showed good correlation between the ANN predicted values and the desired values for various engine performance values and the exhaust emissions. The R² values were very close to 1 and the mean relative error values were less than 9 percent.

Study of performance and emission characteristics of a direct injection diesel engine using rice bran oil ethanol and petrol blends

G. Venkata Subbaiah, K. Raja Gopal and B. Durga Prasad

Abstract:

In this study, influence on the engine performance and exhaust emissions of a naturally aspirated, single cylinder direct injection diesel engine has been experimentally investigated using pure rice bran oil (RBO), and its 2.5%, 5% and 7.5% blends with ethanol (ERBO) and petrol (PRBO). The influence on the viscosity of the RBO with the addition of the ethanol and petrol from 20⁰C to 70⁰C has also been studied. The tests conducted   from no load to full load of the engine with an increment of 20%of the load. The experimental test results showed that the kinematic viscosity reduced maximum by 28.3% and 31.7% with addition of ethanol and petrol respectively. The maximum brake thermal efficiency of 26.83% with ERBO2.5 and 27% with PRBO7.5 was obtained. Among the ethanol blends the minimum brake specific fuel consumption of 0.312 is observed with ERBO7.5 and among the petrol blends the minimum brake specific fuel consumption of 0.299 is observed with PRBO2.5 at full load of the engine. Lower CO emissions of 0.021 with ERBO2.5 and higher CO emissions of 0.032 observed with ERBO7.5. The CO emissions of petrol blends observed between the values of ethanol blends. The unburnt hydrocarbons increased with load in both the ethanol and petrol blends. The lower NO_x emissions of 920 with ERBO2.5 and higher NO_x emissions of 1045 measured with PRBO7.5. The CO₂ increased to 3.72 with PRBO7.5 and reduced to 2.45 with ERBO7.5. The unused O₂ increased 17.2%with ethanol blends and reduced to 13.1% with petrol blends. The smoke reduced with both the blends and lower value of 34.0% observed with PRBO7.5.