Open Access Original Research Article

Excel Approach for Infiltration Capacity for Different Lands

Alaa Nabil El-Hazek

Journal of Engineering Research and Reports, Page 1-18
DOI: 10.9734/jerr/2018/v2i416702

This paper presents an Excel approach for infiltration capacity for different types of lands. That is to employ the popular Microsoft Excel software to represent the measured infiltration data graphically. Regression analysis is performed for the accumulated infiltration versus the time. Equations are obtained to predict the accumulated infiltration at required times.

Thirty one raw infiltration measurements from various sources are gathered, studied and analyzed applying this approach. Measurements include different types of soil textures and land covers. The infiltration rates are measured by the commonly used infiltrometer. Both single infiltrometer and double infiltrometer are employed.

It is concluded that the presented Polynomial infiltration model of Excel approach for the accumulated infiltration is associated with high accuracy, where the values of coefficient of determination (R2) range between 0.9850 and 0.9998. The obtained equations can help in irrigation processes.

All the gathered raw experimental infiltration measurements are also analyzed employing Horton and Kostiakov infiltration models. It is found that the Polynomial infiltration model of Excel approach has higher accuracy, followed by Kostiakov model, and finally Horton model. The values of different constants of Horton and Kostiakov infiltration models for all cases are obtained. The accuracy of the Polynomial, Horton and Kostiakov infiltration models are studied considering the types of soil texture and land cover.

Investigating the constants A, B and C of the obtained equation of the polynomial infiltration model of Excel approach, it is found that all A values are negative, all B values are positive, and all C values are positive except for sandy clay and sandy clay loam soils. There is no specific trend for the effect of the associated land cover on constants A, B, and C except for loamy sand soil, where B and C values for bare land are greater than their values for irrigated land.

Open Access Original Research Article

Reliability Assessment of a Base Transceiver Station Using 2-Parameter Weibull Distribution Method

Onoriode K. Idiapho, William E. Odinikuku

Journal of Engineering Research and Reports, Page 1-15
DOI: 10.9734/jerr/2018/v2i416705

About 80% interruptions of cellular network availability occur due to power outage on BTS stations and reliability analysis of these systems is yet to receive exhaustive studies. Most network providers solely depend on generating power on their BTS sites using diesel generators since the grid power is least reliable, but the frequency of power outages from the diesel generators is alarming, hence, the need to analyse the reliability of these generators and their maintenance routine in relation to the site availability.

In this study, the reliability of a Base Transceiver Station (BTS) is assessed by analysis of data obtained within a period of six months from four BTS sites used as case study using 2-parameter Weibull failure distribution method. The failure times of each BTS site were rank-ordered and the estimates of Weibull parameters θ and β were obtained from Weibull least-squares plots.

The Weibull plots for the four BTS sites had a good index of fit which shows that a strong linear relationship exists. The value of the shape parameter (β) was found to be between the range of 1< β < 3 for all the BTS sites studied. This means that the probability density function is skewed and the failure rate of the BTS sites is increasing. The reliability of each BTS site was successfully computed. The reliability of the four BTS sites was found to be increasing as their values of scale parameter, θ increases. From the results obtained, BTS site RV0144 had the highest reliability while BTS site RV0248 had the lowest reliability.

Open Access Original Research Article

Comparative Study of Fluid Package on Extractive Distillation of Ethanol-water Mixture Using Pure Glycerol and Ethylene Glycol as Extracting Solvents

O. J. Odejobi, O. R. Oladokun, F. J. Ajeigbe

Journal of Engineering Research and Reports, Page 1-12
DOI: 10.9734/jerr/2018/v2i416707

The comparative study of Peng Robinson Strygek Vera (PRSV) and Non-Random Two Liquid (NRTL) fluid packages on the extractive distillation of ethanol-water mixture was done using pure glycerol and ethylene glycol as extracting agents. The process was simulated using HYSYS V. 8.4. Pure glycerol and ethylene glycol-glycerol mixture were used as separating agents. The results showed the highest molar composition of ethanol in the distillate at the solvent feed rate of 80 kmol/hr when pure glycerol was used with NRTL fluid package. With the PRSV fluid package the highest ethanol in the distillate was obtained at pure glycerol feed rate of 50 kmol/hr. The ethanol fraction in the distillate was decreasing with increasing ethylene glycol and decreasing glycerol in the ethylene glycol-glycerol mixture. The comparative study of the base case and alternative designs showed high ethanol composition in distillate in the range of 99.46 - 99.96% and 99.96 - 99.67% for NRTL and PRSV fluid package, respectively. It was concluded from the study that the PRSV fluid package could save cost of operation because of lower solvent requirement and energy consumption in the reboiler for both the base case and alternative designs.

Open Access Original Research Article

A Numerical Simulation of Meshes Mending Used in the Three-dimensional Porthole Die Extrusion of Thin Wall Profiles

Shao-Yi Hsia

Journal of Engineering Research and Reports, Page 1-14
DOI: 10.9734/jerr/2018/v2i416711

Aims: The variety of aluminium products used in many industries (e.g., aviation, railroad, and transport) drive the need for an urgent increase in aluminium feedstock. Improved aluminium extrusion forming and mold design guarantee product quality, shorten production time, and enhance mold life. We analyse and discuss the problems resulting from the simulation and analysis of thin-layer aluminium alloy rims by focusing on porthole die extrusion for bicycles. In general, when analysing with CAE, the billet going from portholes to the welding chamber in the hot extrusion forming process indicates that mesh penetration during remesh causes volume loss and stops the simulation. This is especially serious on thin wall products.

Methodology: In this study, applying mesh mending to extrusion of the billet could solve this problem, and the previous issue of mesh contact causing volume disappearance would not appear during simulation. After solving the remesh problem, the optimisation method in the Taguchi Method could be utilised to modify the hot extrusion mold and analyse its existing speed to avoid uneven forming.

Results: Our analysis simultaneously examined stress, strain, velocity gradient, and product formation to understand the relationships between parameters and extrusion load as well as forming defects caused by thin wall extrusion. It is expected to provide a specifically practicable analysis model for aluminium extrusion.

Conclusion: Comparing the simulation size with design size ensures accuracy. The maximum size error was 8.70% at a size of 0.92mm, and the maximum error of the rest of the sizes was about ±5%, which was acceptable in this study.

Open Access Original Research Article

Improvement on Semiconductor Substrate Design with Package Modeling and Simulation for Mitigation of Delamination and Voids

Frederick Ray I. Gomez, Rammil A. Seguido

Journal of Engineering Research and Reports, Page 1-9
DOI: 10.9734/jerr/2018/v2i416712

This technical paper presents the challenges encountered in the development of a compact and thinner package that incorporates multiple or stacked dice in one. For the case of this paper, Die1 (bottom die) is smaller than Die2 (top die) and must be the first one to be die-bonded, making the internal construction an unbalanced stacked dice. Typically, stacked dice are in pyramid layout, wherein a single large bottom die supports smaller top die. Nonetheless, success is measured when there is a solution to control or mitigate die-attach voids and eliminate or significantly minimise delamination for unbalanced stacked dice as mentioned. Ultimately, the paper presents the understanding of the factors involved and the package design optimisation approach used to produce a successful unbalanced stacked die in a thin package using a thin substrate.