Al-Khwarizmi Engineering Journal,
Vol.10, No. 2 (2014)
Ameel Mohammed Rahman Al-Mayah
Shatha Kadhum Muallah
Aseel Abd Al-Jabbar
Prediction of Oxygen Mass Transfer Coefficients in Stirred Bioreactor with Rushton Turbine Impeller for Simulated (Non-Microbial) Medias.
Ali M. Hameed
Ramzy S. Hamied
Zainab Y. Shnain
Drag-Reducing Agent for Aqueous Liquid Flowing in Turbulent Mode through Pipelines.
In this study, mucilage was extracted from Malabar spinach and tested for drag-reducing properties in aqueous liquids flowing through pipelines. Friction produced by liquids flowing in turbulent mode through pipelines increase power consumption. Drag-reducing agents (DRA) such as polymers, suspended solids and surfactants are used to reduce power losses. There is a demand for natural, biodegradable DRA and mucilage is emerging as an attractive alternative to conventional DRAs. Literature review revealed that very little research has been done on the drag-reducing properties of this mucilage and there is an opportunity to explore the potential applications of mucilage from Malabar spinach. An experimental piping rig was used to study the DR properties of the mucilage on water under the effect of varying pipe dimensions and mucilage concentrations. It is shown that these additives can dramatically reduce friction drag provided that the flow is occurring under turbulent conditions. Experimental results also show that DR increases when the mucilage concentration increases.
Abbas H. Sulaymon
Muna Yousif Abdul-Ahad
Abeer I. Alwared
Removal Water Turbidity by Crumb Rubber Media.
The removal of water turbidity by using crumb rubber filter was investigated .The present study was conducted to evaluate the effect of variation of influent water turbidity (10, 25 and 50 NTU), media size (0.6and 1.14mm), filtration rate (25, 45 and 65 l/hr) and bed depth (30 and 60 cm) on the performance of mono crumb rubber filter in response to the effluent filtered water turbidity and head loss development, and compare it with that of conventional sand filter.
Results revealed that 25 l/hr flow rate and 25 NTU influent turbidity were the best operating conditions. smaller media size and higher bed depth gave the best removal efficiency while higher media size and small bed depth gave lower head loss. The optimum results show that 92.7% removal efficiency and 8.3 mm head loss. The comparison results show that at constant operating conditions, pressure drop for crumb rubber filter is lower than conventional sand filter; about 42% reduction in pressure drop than sand filter and the conventional sand filter has a little enhancement in removal efficiency than crumb rubber filter, 96.8% for sand while for crumb rubber 92.7%.
Comparisons of Mechanical Properties of sub-mm Lead Based and Lead Free Based Solder Using in Manufacturing of Printed Circuits.
This study investigates the mechanical compression properties of tin-lead and lead-free alloy spherical balls, using more than 500 samples to identify statistical variability in the properties in each alloy. Isothermal aging was done to study and compare the aging effect on the microstructure and properties.
The results showed significant elastic and plastic anisotropy of tin phase in lead-free tin based solder and that was compared with simulation using a Crystal Plasticity Finite Element (CPEF) method that has the anisotropy of Sn installed. The results and experiments were in good agreement, indicating the range of values expected with anisotropic properties.
Utilizing a Magnetic Abrasive Finishing Technique (Maf) Via Adaptive Nero Fuzzy (Anfis).
An experimental study was conducted for measuring the quality of surface finishing roughness using magnetic abrasive finishing technique (MAF) on brass plate which is very difficult to be polish by a conventional machining process where the cost is high and much more susceptible to surface damage as compared to other materials. Four operation parameters were studied, the gap between the work piece and the electromagnetic inductor, the current that generate the flux, the rotational Spindale speed and amount of abrasive powder size considering constant linear feed movement between machine head and workpiece. Adaptive Neuro fuzzy inference system (ANFIS) was implemented for evaluation of a series of experiments and a verification with respect to specimen roughness change has been optimized and usefully achieved by obtained results were an average of the error between the surface roughness predicted by model simulation and that of direct measure is 2.0222 %.
Hussain J. M.Alalkawi
Saad A. Khuder Al Saraf
Abdul-Jabar H. Ali
A new Cumulative Damage Model for Fatigue Life Prediction under Shot Peening Treatment.
In this paper, fatigue damage accumulation were studied using many methods i.e.Corton-Dalon (CD),Corton-Dalon-Marsh(CDM) ,new non-linear model and experimental method. The prediction of fatigue lifetimes based on the two classical methods, Corton-Dalon (CD)andCorton-Dalon-Marsh (CDM), are uneconomic and non-conservative respectively. However satisfactory predictions were obtained by applying the proposed non-linear model (present model) for medium carbon steel compared with experimental work. Many shortcomings of the two classical methods are related to their inability to take into account the surface treatment effect as shot peening. It is clear that the new model shows that a much better and conservative prediction of fatigue life in comparison with CD and CDM methods. The prediction of the present model gave slightly below the experimental data while the CDM gave overestimate prediction and CD showed strongly underestimates the life of specimens.
Amel S. Merzah
Mohammed H. Hafiz
Sarah k. Mohammed
Corrosion control of Buried Low Carbon Steel Structure by Using Alteration Medias method.