The University of Anbar is an Iraqi university located in Ramadi, Anbar, Iraq. It was founded in 1987 with a college of education and a college of girls education, and then expanded until it reached university status in 2011 with 19 colleges. The university experienced a hostage crisis in 2014 when gunmen linked to the Islamic State of Iraq and the Levant briefly took students hostage at the Ramadi campus. Wikipedia.
Ahmed H.E.,University of Anbar |
Mohammed H.A.,University of Technology Malaysia |
Yusoff M.Z.,University of Tenaga Nasional
Renewable and Sustainable Energy Reviews | Year: 2012
The subject of heat transfer enhancement has significant interest to develop the compact heat exchangers in order to obtain a high efficiency, low cost, light weight, and size as small as possible. Therefore, energy cost and environmental considerations are going on to encourage attempts to invent better performance over the existence designs. Streamwise vortices can be generated using small flow manipulators or protrusions such as wings and winglets configurations. Single-pair, single row, or two dimensional array of vortex generators (VGs) can be punched, mounted, attached or embedded in the boundary layer of flow channel. VGs generate longitudinal and transverse vortices, while longitudinal vortices are more efficient for heat transfer enhancement than transverse vortices. A dramatic augmentation in thermal performance of the thermal system can be achieved but pressure drop penalty is existed. Several parameters have been overviewed in this paper, which have pronounced effect on the convective heat transfer coefficient and pressure drop penalty. These parameters are: attack angle of VG, geometry of VG, standard and novel types of VG, spacing between the VG tips, number of pairs of VGs in the flow direction, rectangular or circular array arrangement of VGs, common-flow upper (CFU) or common-flow down (CFD) configuration of VG, pointing up (PU) or pointing down (PD) arrangement of VG with flow direction, Re number, channel aspect ratio, number of tubes of fin-tube heat exchanges (HE), circular or oval tubes of fin-tube HE, and location of VG respect to the tube of HE or from leading edge of the channel. This paper gives an overview about the early studies done in order to improve the performance of thermal systems with minimal pressure losses to derive systems with less negative impact on the environment and high level of energy economic. This study also provides an outlook for future work using nanofluids with vortex generators. This article is also summarizes the recent experimental and numerical developments on the thermal conductivity measurements of nanofluids, thermal conductivity enhancement, convection and conduction heat transfer, some applications, main problems and suggestions for future works. © 2012 Elsevier Ltd.
Ahmed H.E.,University of Anbar
Applied Thermal Engineering | Year: 2016
Enhancing the thermal design of plate-fin heat sink (PFHS) leads to minimize their size and weight, and then improve the heat removal in consequently increase the speed of electronic devices. In this numerical study, an innovative thermal design of PFHS is suggested by inserting ribs in between channels in different sizes, positions, numbers and orientations in order to get an optimal thermal design of this kind of heat sinks. The two main objectives of this study are; investigating the effect of ribs on PFHS while the number of fins is kept constant, second is inserting ribs with reducing the number of fins simultaneously. Two types of reductions are investigated here, first is substrate material reduction by reducing the number of fins and adding ribs simultaneously, second is pumping power reduction by keeping the number of fins and inserting ribs with reducing the pumping of air flow to get the same thermal performance of the original heat sink (without ribs). The concrete findings show that ribbed plate-fin heat sink (RPFHS) provides thermal performance of 1.55 times greater than PFHS under corresponding conditions. But this enhancement reduces when the number of ribs increases. For the same thermal performance, the pumping power of RPFHS is reduced to 69.65% compared to PFHS case. In addition, RPFHS having five channels with 15 ribs shows hydrothermal performance of 1.37 times better than PFHS having nine channels, with reduction in the substrate material of 27.24%. © 2016 Elsevier Ltd. All rights reserved.
Al-Ani Z.R.,University of Anbar
Saudi Medical Journal | Year: 2010
Objectives: To study the association of consanguinity as a risk factor for congenital heart diseases (CHDS). Methods: Patients with suggestive signs of CHD admitted to the Al-Ramadi Maternity and Children Hospital, Al-Anbar Governorate, Iraq from January 2009 to January 2010 were subject to diagnostic investigations. Case data includes: name, age, gender, and cause of admission. Parents' data includes: age, residence, degree of consanguinity, and history of family recurrent CHDS. Tree controls to one case (3:1) were selected to compare their consanguinity with the CHD cases. Odds ratio was used for the measurement of consanguinity and other variable risks on CHD occurrence. Results: Te CHD cases were 86. Selected controls were 258 non-CHD cases. Te most recorded subtypes were ventricular septal defect (VSD), atrial septal defect (ASD), and tetralogy of fallot (TOF). Consanguinity was found in 78% of cases and 43.3% in controls. First cousin consanguinity comprised 66.2% in cases and 35.6% in controls from all their marriages. Consanguinity was found a significant risk factor, more affecting the VSD and ASD than TOF subtypes, while parental age and infant gender were not found as risk factors. Conclusion: Consanguinity proved to be a risk factor for CHD. Further social education of the risks of consanguineous marriages in this tribal population is needed to reduce the prevalence of these morbid and mortal anomalies.
Najim K.B.,University of Anbar
Energy and Buildings | Year: 2014
Improving thermal performance of external load-bearing walls in residential buildings could be the most effective way in reducing energy consumption for air-conditioning purpose in housing sector. The aim of this study is to characterize the already existing external load-bearing walls in the residential buildings, in Iraq, in terms of the thermo-physical properties of the used materials. In addition to that, the assemblies of these materials, i.e. wall configurations have been evaluated regarding the steady-state thermal performance and dynamic thermal admittance parameters. Different scenarios were suggested in order to improve the thermal performance of the existing walls. The effect of the binding material (cement mortar) on the global thermal performance of the wall fabrics has also been investigated by utilizing image analysis to calculate the percentage of this material from whole wall. The results showed that binding material has no significant effect on the thermal performance for the studied walls. Gypsum coating layer can be removed as it has marginal effect on the evaluated properties. It was found that involving two air-cavities (internally and externally) has much effect on the walls thermal performance than other approaches. © 2014 Elsevier B.V. All rights reserved.
Ahmed T.M.,University of Anbar
International Journal of Pavement Engineering | Year: 2016
This study investigates the fatigue performance of hot mix asphalt (HMA) tested using a dynamic shear rheometer (DSR) under controlled stress test mode. Cylindrical DSR samples of 12 mm in diameter and 50 mm in height were prepared from a full HMA using coring technique to be used in fatigue test. Regarding fatigue evaluation, a fatigue index (FIR) has been developed based on the relationship of stress–pseudo strain hysteresis loop to be used in evaluating fatigue performance. The average values of FIR, in the relationship of FIR against normalised shear modulus, were calculated in the range of normalised shear modulus (0.85–0.20) to be used in evaluating the fatigue performance of tested samples. The FIR outcomes were in agreement in respect to the ranking order with the results from well-known approaches that have also been used for evaluating the fatigue performance, such as the energy ratio and the traditional approaches. In this study, limestone and granite aggregates were used with two binder grades: 40/60 and 160/220 to prepare four mixtures with two different gradations: gap-graded hot rolled asphalt and continuously graded dense bitumen macadam. The study demonstrated that the DSR instrument could be used to perform fatigue testing of full HMA. Also, limestone mixes showed better fatigue performance than granite. © 2016 Informa UK Limited, trading as Taylor & Francis Group