Mechanization and Import Substitution in Zimbabwean Farmers' Equipment: A Case Study of the Revitalization of an Abandoned Tractor Trailer
Drill String Vibrational Analysis and Parametric Optimization for a Portable Water Well Rig Development
An Efficient Deep Neural Network with Amplifying Sine Unit for Nonlinear Oscillatory Systems
The Occupational Directness of Nanorobots in Medical Surgeries
Recent Trends in Solar Thermal Cooling Technologies
Design of Oil-Ammonia Separator for Refrigeration Systems
A Review on Mechanical and Tribological Characteristics of Hybrid Composites
Design and Experimental Investigation of a Natural Draft Improved Biomass Cookstove
Progressive Development of Various Production and Refining Process of Biodiesel
Optimization of Wire-ED Turning Process Parameters by Taguchi-Grey Relational Analysis
Evaluation Of Mechanical Behavior Of Al-Alloy/SiC Metal Matrix Composites With Respect To Their Constituents Using Taguchi Techniques
Multistage Extractive Desulfurization of Liquid Fuel by Ionic Liquids
Isomorphism Identification of Compound Kinematic Chain and Their Mechanism
Development of Electroplating Setup for Plating Abs Plastics
A Comprehensive Review of Biodiesel Application in IDI Engines with Property Improving Additives
Gas turbine disc wheels usually operate at high temperatures. The hot gases contact the turbine rotor rim and blades causing these parts operating under extremely high temperature. Even the different cooling methods were used to lower the disc temperatures, it still remains at the high temperature due to continuous contact between rim and hot gases. Plus, even the cooling methods can reduce the temperature in central rotor area, it in turns increases the temperature gradients which produces the thermal stresses in gas turbine disks. To help understanding the mechanism of centrifugal and thermal stresses generated in gas turbine, a computer-aided modeling and simulation methodology is developed in this research paper to determine the effect of critical turbine functioning parameters and improve the turbine performance. So far, there are few related technical papers published in this research field. This paper introduces the computer-aided modeling and simulation methodology to determine the mechanical and thermal stresses produced in gas turbine. One prototype has been built and tested to validate the results from computational simulation. All gained results can potentially help future gas turbine design.
In this study, residual stress measurement in resistance spot welded aluminum joint is investigated. A pair of 2 mm thickness aluminum 6061-T6 sheets are prepared and welded according to the American Welding Society (AWS) standard. Due to the small dimensions of nugget and heat affected zone in this process, the X-ray diffraction method utilized for residual stress measurement. The results show that the outside areas of the nugget are influenced by the preliminary sandpaper grinding process. Also, residual stress measurement on the edge of the nugget shows a wide deviation which is due to the changes in surface height. The results imply that, the residual stress measurements in resistance spot welded joints are limited within nugget area for which the grinding stresses were relaxed by the high temperature during welding. The observed residual stresses at this zone show tensile stresses at surface which increase from center toward the edge of the nugget.
This paper presents the detailed discussions on fabrication of Aluminium - silicon carbide (10% by weight of particles) and boron carbide (5% by weight of particles) Hybrid Metal Matrix Composites (Al/SiC/B4C — MMC) using stir casting method. SiC and a B4C particle range from 30µm to 50 µm. The cylindrical rods of diameter 60 mm and length 250 mm are fabricated and subsequently machined using medium duty lathe of 2 kW spindle power to study the machinability issues of Hybrid MMC using Poly Crystalline Diamond (PCD) insert of 1600 grade. The optimum machining parameters have been identified by a composite desirability value obtained from desirability function analysis as the performance index, and significant contribution of parameters can then be determined by analysis of variance. Confirmation test is also conducted to validate the test result. Experimental results have shown that machining performance can be improved effectively through this approach. Results show at higher cutting speeds, good surface finish is obtained with faster tool wear. It is concluded that, tool wear and cutting force are directly proportional to the cutting speed, where as surface roughness is inversely proportional to the cutting speed. Percentage of error obtained between experimental value and predicted value is within the limit.
In the present work microwave energy has been explored as a new processing method of joining bulk metallic materials. Microwave joining of Inconel 718 plates has been successfully carried out using a multimode applicator at a frequency of 2.45 GHz and a power of 900 W. Principles of microwave hybrid heating (MHH) were effectively employed for joining of Inconel 718 plates by placing an interlayer of Ni powder of average thickness of about 0.2 mm between the interfacing surfaces. The susceptor material, charcoal was used for initial coupling of microwave with powder interlayer. Resulting joints were characterized using X ray diffraction (XRD), (SEM) scanning electron microscope and (EPMA) electron probe micro analysis. The back scattered electron (BSE) microgaph confirm that the faying surfaces were well fused and metallurgical bonding takes place on either side of the base material. Tests were conducted to examine the joint tensile strength. The analysis shows that the joints have an average strength of 400 MPa with an percentage elongation of 6 percent.
In the present work, the response surface methodology (RSM) was used for the modeling of weld bead penetration during submerged arc welding. For this, the fluxes of varying constituents have been studied and with the help of proposed model, departure from the predicted value is studied. A validation exercise was performed with the help of developed agglomerated fluxes. The MnO, CaF2, MgO, NiO and Fe-Cr constituents of developed agglomerated fluxes added into the main constituents CaO, Sio2 and Al2o3,were chosen as variables to study the performance in terms of penetration. It was concluded that the model for prediction of penetration value for the specified range was in close proximity with the actual results obtained.
In this era of nano and precise accuracies we have great concern of productivity and finish in all levels of manufacturing which also includes casting process. In casting process we prepare casts, for this we require to carry the molten metal for which we require a device to carry i.e. ladle. A ladle is a component used for carrying the molten metal in the casting process and it undergoes a considerable heat loss. The molten metal gets solidified in the interior surface of the ladle and it is called as skull. To increase the productivity and yield rate we surely require an alternative solution, to reduce the skull formation in the ladle. In this paper it is focused to give theoretical and analytical information about the heat loss; problem of skull in the ladle. The Mathematical formulation used for solving of the problem is presented. It also presents the results graphically and comparisons will be laid out using MAT LAB software.
