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joe-2210
Numerical Study of Optimum Configuration of Unconventional Airfoil with Steps and Rotating Cylinder for Best Aerodynamics Performance
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Numerical study of separation control on symmetrical airfoil, four digits (NACA

0012) by using rotating cylinder with double steps on its upper surface based on the computation of Reynolds-average Navier- Stokes equations was carried out to find the optimum configuration of unconventional airfoil for best aerodynamics performance. A model based on collocated Finite Volume Method was developed to solve the governing equations on a body-fitted coordinate system. A revised (k-w) model was proposed as a known turbulence model. This model was adapted to simulate the control effects of rotating cylinder. Numerical solutions were performed for flow around unconventional airfoil with cylinder to main stream velocities ratio in the range of 1 to 4 and for various positions of the steps on the airfoil from the leading edge, 0.1c, 0.2c, 0.3c, 0.4c, 0.5c for the first step and 0.5c, 0.6c, 0.7c, 0.8c for the second step with constant step depth and length of 0.03c and 0.125c respectively. Reynolds number of 700,000 which was based on the cord length (c), with angle of attacks 0, 5, 8, 10, 12, 15 degrees was considered for the assessment of the unconventional airfoil performance. The numerical investigation showed that the optimum configuration for the unconventional airfoil was found to be at velocities ratio (U/U∞=4) with the steps positions at 0.5c and 0.8c for best airfoil performance.

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Publication Date
Thu Aug 31 2017
Journal Name
Journal Of Engineering
Optimum Dimensions of Hydraulic Structures and Foundation Using Genetic Algorithm coupled with Artificial Neural Network
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      A model using the artificial neural networks and genetic algorithm technique is developed for obtaining optimum dimensions of the foundation length and protections of small hydraulic structures. The procedure involves optimizing an objective function comprising a weighted summation of the state variables. The decision variables considered in the optimization are the upstream and downstream cutoffs lengths and their angles of inclination, the foundation length, and the length of the downstream soil protection. These were obtained for a given maximum difference in head, depth of impervious layer and degree of anisotropy. The optimization carried out is subjected to constraints that ensure a safe structure aga

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Publication Date
Mon Nov 03 2008
Journal Name
All Days
Correlations for Optimum Separation Pressures for Sequential Field Separation System
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ABSRACT<p>A study has been done to find the optimum separators pressures of separation stations. Stage separation of oil and gas is accomplished with a series of separators operating at sequentially reduced pressures. Liquid discharged from a higher pressure separator into the lower pressure separator. The set of working separators pressures which yield maximum recovery of liquid hydrocarbon from the well fluid is the optimum set of pressures which is the target of this work.</p><p>Computer model is used to find the optimum separators pressures. The model employs the Peng-Robinson equation of state for volatile oil. Application of this model shows good improvement of al</p> ... Show More
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Publication Date
Mon Nov 01 2010
Journal Name
All Days
Optimum Separation Pressure for Heavy Oils Sequential Separation
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Abstract<p>The estimation of quantity of liquid that is collected from gas/oil separation system is a very complex task because it requires the application of the flash calculations which needs to solve the cubic equation of state and to use some numerical techniques. These difficulties can be overcome by a computer model which requires a lot of experimental data, long time, and experience.</p><p>This paper adopts a new technique to simplify this problem. It suggests new correlations for optimum separator pressure for separation station of heavy oils. The correlations have been achieved for two- and three- stage separation systems.</p><p>The co</p> ... Show More
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Publication Date
Thu Mar 18 2010
Journal Name
Spe Projects, Facilities & Construction
Correlating Optimum Stage Pressure for Sequential Separator Systems
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Summary<p>A study to find the optimum separators pressures of separation stations has been performed. Stage separation of oil and gas is accomplished with a series of separators operating at sequentially reduced pressures. Liquid is discharged from a higher-pressure separator into the lower-pressure separator. The set of working separator pressures that yields maximum recovery of liquid hydrocarbon from the well fluid is the optimum set of pressures, which is the target of this work.</p><p>A computer model is used to find the optimum separator pressures. The model employs the Peng-Robinson equation of state (Peng and Robinson 1976) for volatile oil. The application of t</p> ... Show More
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Publication Date
Sat Oct 30 2021
Journal Name
Iraqi Journal Of Science
Small Binary Codebook Design for Image Compression Depending on Rotating Blocks
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     The searching process using a binary codebook of combined Block Truncation Coding (BTC) method and Vector Quantization (VQ), i.e. a full codebook search for each input image vector to find the best matched code word in the codebook, requires a long time.   Therefore, in this paper, after designing a small binary codebook, we adopted a new method by rotating each binary code word in this codebook into 900 to 2700 step 900 directions. Then, we systematized each code word depending on its angle  to involve four types of binary code books (i.e. Pour when , Flat when  , Vertical when, or Zigzag). The proposed scheme was used for decreasing the time of the coding procedure, with very small distortion per block, by designing s

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
MECHANICAL DEGRADATION OF HIGH MOLECULAR WEIGHT POLYMER WITH SURFACTANT ADDITION IN A ROTATING DISK APPARATUS
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Mechanical degradation hampers the practical usage of polymers for turbulent drag reduction
application. Mechanical degradation refers to the chemical process in which the activation energy of
polymer chain scission is exceeded by mechanical action on the polymer chain, and bond rupture
occurs. When a water-soluble polymer and surfactant are mixed in water solution, the specific structures
(aggregates) are formed, in which polymer film is formed around micelle. In this work, Xanthan gum (XG) –
Sodium lauryl ether sulfate (SELS) complex formation and its effect on percentage viscosity reduction
(%VR) was studied. It was found that SELS surfactant reduced the mechanical degradation of XG much
more efficiently than th

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Publication Date
Sat Dec 11 2021
Journal Name
Engineering, Technology &amp; Applied Science Research
Behavior of RC Beams Strengthened with NSM-CFRP Strips Subjected to Fire Exposure: A Numerical Study
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The use of Near-Surface Mounted (NSM) Carbon-Fiber-Reinforced Polymer (CFRP) strips is an efficient technology for increasing flexural and shear strength or for repairing damaged Reinforced Concrete (RC) members. This strengthening method is a promising technology. However, the thin layer of concrete covering the NSM-CFRP strips is not adequate to resist heat effect when directly exposed to a fire or at a high temperature. There is clear evidence that the strength and stiffness of CFRPs severely deteriorate at high temperatures. Therefore, in terms of fire resistance, the NSM technique has a significant defect. Thus, it is very important to develop a set of efficient fire protection systems to overcome these disadvantages. This pape

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Publication Date
Mon Oct 01 2012
Journal Name
Computers &amp; Mathematics With Applications
Boundary element formulations for the numerical solution of two-dimensional diffusion problems with variable coefficients
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Publication Date
Tue Dec 15 2015
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Determination of some Optimum Conditions for Bioremediation of Some Heavy Metals by Saccharomyces cerevisiae: Determination of some Optimum Conditions for Bioremediation of Some Heavy Metals by Saccharomyces cerevisiae
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The study aimed to determine of some Optimum conditions for bioremediation and removing of seven mineral elements included hexavalent chromium, nickel, cobalt, cadmium, lead, iron and copper as either alone or in group by living and heat treated cells of baker’s yeast Saccharomyces cerevisiae. The dried baker's yeast from Aldnaamaya China Company was used in this study. Biochemical tests was used to ensure yeast belonging to S. cerevisiae and then used to remove the mentioned mineral elementes under different conditions which included incubation period, pH, and temperature. It was found that the best of these conditions was 60 minutes for duration of incubation, 6 for pH, 25 ᵒC for temperature. During the study the behavior of living

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Publication Date
Sun Feb 05 2017
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
STUDY THE OPTIMUM CONDITIONS FOR THE REMOVAL OF HEAVY METAL ELEMENTS FROM AQUEOUS SOLUTIONS USING CONTAMINATED BACTERIA Bacillus subtilis LOCALLY ISOLATED: STUDY THE OPTIMUM CONDITIONS FOR THE REMOVAL OF HEAVY METAL ELEMENTS FROM AQUEOUS SOLUTIONS USING CONTAMINATED BACTERIA Bacillus subtilis LOCALLY ISOLATED
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We studied the effect of certain environmental conditions for removing heavy metal elements from contaminated aqueous solutions (Cd, Cu, Pb, Fe, Zn, Ni, Cr) using the bacterium Bacillus subtilis to appoint the optimal conditions for removal ,The best optimum temperature range for two isolate was 30-35○C while the hydrogen number for the maximum mineral removal range was 6-7. The best primary mineral removal was 100 mg/L, while the maximum removal for all minerals was obtained after 6 hrs of Cu element time and the maximum removal efficiency was obtained after 24 hrs of Cu element. The results have proved that the best aeration for maximum removal was obtained at rotation speed of 150 rpm/minute. Inoculums of 5ml/100ml which contained 1

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