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Article
Improvement Heavy Oil Transportation in Pipelines (Laboratory study)

Authors: Ayad A. Abdulrazak --- Haidar A. Faris
Journal: Journal of Petroleum Research & Studies مجلة البحوث والدراسات النفطية ISSN: 22205381 Year: 2016 Volume: 272 Issue: 13 Pages: 200-209
Publisher: Ministry of Oil وزارة النفط

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Abstract

Since from the past, drag has been identified as the main reason for the loss of energy in pipelines and other similar transportation channels. The contribution of this drag is due to mainly viscous of the flow as well as friction against the pipe walls. These energy losses can be identified through pressure drop, which will results in more pumping power consumption.Due to their very high viscosity heavy oil cannot be transported as such in pipelines and required additional treatments [1].This work studied flow increase (%FI) in heavy oil at different flow rates (2 to 10 m3/hr) in two pipes (0.0381 m & 0.0508 m) ID. By using different additives (toluene and naphtha) with different concentrations (2, 4, 6, 8 and 10) %wt at 27ᵒC.The results of this study showed Increasing values of FI % and Maximum Dr% of 40.48% and 37.03 % were obtained using heavy oil containing 10% wt of naphtha flowing in pipes of 0.0508 and 0.0381 m I.D. at 27°C respectively.Increasing values of %Dr with increasing of Reynolds number, fluid velocity and additive concentration, the used additives (toluene and naphtha) reduce the high viscosity of used heavy oil, and naphtha is more efficient as viscosity reducer than toluene.All these results show treatment heavy oil and improvement their transport in pipelines.


Article
Problems of Heavy Oil Transportation in Pipelines And Reduction of High Viscosity

Authors: Ayad A. Abdulrazak --- Mohammed Al-Khatieb --- Haidar A. Faris
Journal: Iraqi Journal of Chemical and Petroleum Engineering المجلة العراقية للهندسة الكيمياوية وهندسة النفط ISSN: 19974884/E26180707 Year: 2015 Volume: 16 Issue: 3 Pages: 1-9
Publisher: Baghdad University جامعة بغداد

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Abstract

Drag has long been identified as the main reason for the loss of energy in fluid transmission like pipelines and other similar transportation channels. The main contributor to this drag is the viscosity as well as friction against the pipe walls, which will results in more pumping power consumption. The aim in this study was first to understand the role of additives in the viscosity reduction and secondly to evaluate the drag reduction efficiency when blending with different solvents. This research investigated flow increase (%FI) in heavy oil at different flow rates (2 to 10 m3/hr) in two pipes (0.0381 m & 0.0508 m) ID By using different additives (toluene and naphtha) with different concentrations (2, 4, 6, 8 and 10) wt. % at 35ᵒ C.The results of this study showed the following:•Increasing values of Dr% and FI% for all drag reducing agents with heavy oil. Increasing values of Dr% with increasing of Reynolds number, fluid velocity and additive concentration.•With the larger pipe diameter, performances of drag reduction occur is much better than smaller pipe diameter.•The additives (toluene and naphtha) reduce the high viscosity of used heavy oil.•Naphtha is more efficient as viscosity reducer than toluene. Finally, all these results help the understanding of the flow properties of heavy oils and aim to contribute to the improvement of their transport.

Keywords

Heavy oil --- drag reduction


Article
Hypothetical Evaluation of Stress and Displacement of the Mandible with Chin Cup Therapy Using Various Force Vectors (Finite Element Study)

Authors: Hussain A. Obaidi --- Ayad A. Abdulrazak --- Lomya A. Abdulrahman
Journal: Al-Rafidain Dental Journal مجلة الرافدين لطب الأسنان ISSN: 18121217 Year: 2015 Volume: 15 Issue: 1 Pages: 340-347
Publisher: Mosul University جامعة الموصل

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Abstract

Introduction: Early orthodontic treatment is recommended, since the morphologic pattern of the prognathic face associated with excessive forward mandibular growth is most likely established early in life. The chin cup is the preferred orthopedic appliance for growing children with mandibular prognathism and a normal maxilla. Aims Of Study: Evaluation of the stress and displacements in the mandible from various chin cup force vectors, using three-dimensional finite element model. Materials And Methods: Three-dimensional model of the mandible was modeled and analyzed. Chin cup with 800 g force was applied on the pogonion of the mandible. The direction of the loading vectors were 150, 200, 250, 300, 350, 400 and 900 relative to x axis, then, the mechanical responses in terms of displacement and Von Mises stresses are evaluated. Results: The highest stress levels observed in the condylar, posterior ramus regions and inferior sigmoid notch, and increased as the force vector was transferred away from the condyle. The mandible was displaced in downward and backward direction with the vector passing below and through the condyle (with angles 150, 200 and 250) forward and upward displacement was recorded as the force vector move away from the condyle (within 300, 350, 400 and 900). Conclusions: With the limitations of modeling, boundary conditions, and solution assumptions, chin cup applied in various directions produce different force vectors, which induce different stress and displacements. The force vector is an important determinant of the orthopedic effects of the chin cup and therefore should be carefully considered.

Keywords

Chin cup --- finite element.

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