Open Access Original Research Article

Die Attach Process Defect Mitigation through Design Improvement on Anvil Block Tooling

Rennier S. Rodriguez, Frederick Ray I. Gomez, Bryan Christian S. Bacquian

Journal of Engineering Research and Reports, Page 1-6
DOI: 10.9734/jerr/2020/v17i217182

Process improvement through modification in the design of indirect material is one potential direction to improve the productivity during assembly manufacturing. In this paper, an augmented design of anvil block is presented to reduce the crumpled strips, leadframe bending and dents, uneven bonding of die, localized insufficient epoxy, and misaligned die encountered during the conversion and setup stage. The implementation of the augmented design improves the current assembly practice through eliminating the replacement of anvil block that is the cause of misalignment on the indexer handler of the die attach machine. Through this design, the selection of appropriate vacuum hole setup can be through the sliding insert only without pulling out the anvil block from the machine.

Open Access Original Research Article

Kinetics of Anaerobic Digestion of Unripe Plantain Peels

Chinenyenwa Nkeiruka Nweke, Joseph Tagbo Nwabanne

Journal of Engineering Research and Reports, Page 7-17
DOI: 10.9734/jerr/2020/v17i217183

This study was carried out to investigate the biogas production obtained from anaerobic digestion of unripe plantain peels (PP) and the kinetics of the digestion process. 400 g of dried and shredded unripe plantain peels were mixed with 200 ml of water and put into 1 L digester and observed for biogas for hydraulic retention time (HRT) of 15 days by the method of downwards displacement. The cumulative biogas volume obtained after digestion was 285 ml. The COD removal efficiency of 72.5% was achieved. The kinetics of PP digestion was evaluated using first order, Monod, Contois and, Grau second-order models. Results showed that the kinetics of anaerobic digestion of PP followed the first-order model with a constant (K) of 0.095 day-1. Monod kinetics was evaluated and the maximum rate of substrate utilization (K), the half velocity constant (KS), endogenous decay coefficient (Kd), biomass growth yield (Y) and, maximum specific microorganism growth rate (µmax) obtained were 0.7615 day-1, 16.20 mg/l, 0.0047 day-1, 0.0112 mgVSS mgCOD-1 and, 0.009 day-1 respectively. These results revealed that inoculation would be required to increase the rate and volume of biogas production. Both first-order and Monod models gave a high coefficient of determination indicating that first order and Monod models can be used to model the digestion of PP. Contois model gave values of µmax and β as 0.011 day-1 and 0.644 mgCOD mgVSS-1 respectively. The result obtained has shown that the digestion of PP did not follow second-order kinetics.

Open Access Original Research Article

Integration of EMI Shielding Design for Substrate Package Isolation

Frederick Ray I. Gomez, Rennier S. Rodriguez

Journal of Engineering Research and Reports, Page 18-22
DOI: 10.9734/jerr/2020/v17i217184

This paper presents a modified substrate design that would enable a bottom electromagnetic interference (EMI) shielding protection for EMI sensitive integrated unit (IC). The modified substrate design is applied and incorporated to the existing and known shielding technique to fully proof the structure to external interference through the application of EMI shielding layer on the substrate configuration. The EMI shielding layer will be connected to the surface coating (EMI shielding) and ground channel of the substrate and the external board.

Open Access Original Research Article

The Effect of Soil Poissons Ratio on the Response of Buildings with Sufficient Embedment Depth

Ahmed Hafiz Yasseen Essawy

Journal of Engineering Research and Reports, Page 23-33
DOI: 10.9734/jerr/2020/v17i217185

The present study highlights the effect of soil poissons ratio on the response of buildings with sufficient embedment depth. The interaction effect between the structure and its foundation control the dynamic behavior of the structure during seismic analysis. Not only the foundation of structure control the results of seismic analysis but also the embedment depth of the structure increase this effect. The ground motions produced by the seismic excitation at the base of the building are the result of shear deformation in the soil. The effect of the inertial resistance of soil surrounding the basement floors is taken into consideration by adding virtual masses to the basement floors to obtain more accurate shear forces acting on the flexible basement columns. The study calculates the response values at any required time and the maximum response values in addition to its time of occurrence.

Open Access Original Research Article

Analysis of Ethylene Glycol (EG)-based ((Cu-Al2O3), (Cu-TiO2), (TiO2-Al2O3)) Hybrid Nanofluids for Optimal Car Radiator Coolant

J. A. Okello, W. N. Mutuku, A. O. Oyem

Journal of Engineering Research and Reports, Page 34-50
DOI: 10.9734/jerr/2020/v17i217186

Coolants are vital in any automotive since they manage the heat in the internal combustion of the engines by preventing corrosion in the cooling system as well as assist in eradicating the engine’s waste heat. This paper examines three different types of ethylene glycol-based hybrid nanofluids ((Cu-Al2O3), (Cu-TiO2), (TiO2-Al2O3)) to establish their cooling capabilities for industrial cooling applications. The vertical flow of these hybrid nanofluids combination through a semi-infinite convectively heated flat plate mimicking the flow of coolant in car radiator is modeled. The governing non-linear partial differential equations of fluid flow are transformed into a system of coupled non-linear ordinary differential equations using a suitable similarity transformation variables and the numerical solution executed using the shooting technique together with the fourth-order Runge-Kutta-Fehlberg integration scheme. The numerical simulation is executed using MATLAB and results are displayed graphically. The effects of pertinent parameters on velocity, temperature, skin friction, and local Nusselt number are investigated. From the study (Cu-Al2O3  hybrid nanocoolant leads to a rapid decrease in temperature at the boundary layer.