زيد ستار كريم المعموري

An oval cross-sectional-area twin jet were studies experimentally studied under constant heat flux conditions to clarify the effect of both Zn-water nanofluid along with such oval twin jet on the thermal characteristic and provide the lack data in such field. The validation was conducted with comparable study and it showed acceptable deviation. The emerged results referred to that the Nusselt number is remarkably increase as the nanoparticle concentration, Reynold number and the distance between nozzles increase. The higher enhancement was found to be 2.1% at high Reynold number value (Re=1000), S/D=5 and nanoparticle concentration ϕ=0.5.

Heat transfer enhancement is a prominent field which has tremendous demands in all aspects of life, especially in industry and engineering applications. For this and other unseen reasons, a heat transfer enhancement in twin circular jet was studied experimentally by using Al2O3 water nanofluid for various concentrations (0.05, 0.1, 0.15, 0.2, and 0.25) kg/m3. The current study primarily aimed to clarify the effect of major parameters such as nanoparticle concentrations and nozzles height to diameter (Z/D) of such arrangement on heat transfer enhancement. The validation was conducted thoroughly and it showed acceptable deviation with analogous studies. The obtained results indicated that the maximum increase in Nusselt number comparing to base fluid (water) was observed to be about 200% higher than the base fluid at nanoparticle concentration (φ) οf 0.25 kg/m3, Re=2000 and Z/D=4. While the minimum was about 18% higher than the base fluid and detected at φ=0.05 kg/m3, Re=400, and Z/D=7.

The article aimed to determine both numerical and theoretical solution regarding the deflection of a stainless-steel material type 316 in form of rectangular plate having a dimensions of 3 mm thickness, 250 length and 500 mm width of the plate for welding purpose. The theoretical approach which embraced in the current study is the simple plate theory (Kirchhoff's theory) and the derivation was started from this theory to predict the deflection that effect in the plate undergoing dynamic load which are represented by vibration frequency and welding process (thermal temperature) along the plate surface. A vibration action is always correlative to the welding process and causes a deflection in the plate. This deflection was calculated for four mode shape and under various thermal load (welding process). It was found that the maximum deflection during the welding process for the four mode shapes belong to the fourth one with a value of 0.0188 mm, while the lowest one is belonging to the first mode shape with a value of 0.00134 mm. The maximum deviation between the numerical and theoretical approach was found to be less than 5%.

Nowadays, the energy resources are almost depleted due to the tremendous demand. Hence, the efforts were paid worldwide to innovate new heat transfer technique to get satisfying outcomes with less cost. Heat transfer enhancement by surface modification is commonly practiced throughout the last decades because it helps to reduce both the size and cost of heat transport devices. The numerical investigation of forced convective heat transfer inside circular tube with dimpled surface of inline arrangement, the dimple size was denoted in term of d/D, it was in range of ( 1/6 ).under internal turbulent flow conditions has been studied with ZnO water nanofluids of (0.2, 0.6, 0.8 and 1) % volume fractions were used. The size and arrangement of dimples were conducted. The gained outcomes showed the heat transfer coefficient is directly proportional with both dimples size and nanofluids volume fraction. It was concluded a maximum enhancement achieved is 2297 at Reynold number of 12000 and volume fraction of 1. While the poorer performance was 1013 at Reynold number of 6000 and volume fraction 0.2.

A solo passive heat transfer enhancement technique represented by nanoparticle additives was embraced in this study due to the nanofluid technology potentials. A single circular jet (3 mm diameter) was used at Reynold number range of (1000–8000) with nozzle-to-jet Distance (Z) varied from 40 to 70 mm. Validation was conducted prior to commence the experimental tests and an accepted deviations were detected. The obtained outcomes showed the potential of CuO-water nanofluid to improve the heat transfer remarkably. Such enhancement increase as both Reynold number and volume fraction increase. Moreover, the Nozzle-to-target plate distance has the dominant effect over the volume fraction effect. Where the heat transfer decreases as the nozzle-to-target plate (Z) increase even if the volume fraction increase. Eventually, the maximum enhancement in Nusselt number was 2.9% and minimum enhancement was about 0.87%.

A solo passive technique of heat transfer enhancement represented by nanoparticle additives was adopted in this study due to the prominent field of nanofluid technology. Exploration the effect of such important nanofluid technology prompted toward the conduction of current experimental tests using Cu/water nanofluid. A single semi-circular jet was used for Reynold number range of (200-1000) with nozzle-to-jet Distance (Z) varied from 20-35 cm. The obtained outcomes show the potential of Cu/water nanofluid to improve the heat transfer remarkably. Such enhancement increase as both Reynold number and volume fraction increase. On the other hand, the Nozzle-to-target plate distance has the dominant effect over the volume fraction effect. The results showed a remarkable enhancement of Nusselt number at Reynold number of 1000. It was also concluded that the Cu/water nanofluid has good features in enhancement of heat, easy preparation and has good stability

كيفية كتابة بحث علمي اكاديمي عنوان لحلقة نقاشية أقامها قسم الهندسة الميكانيكية في كلية الهندسة بجامعة الكوفة. واوضح المعموري كيفية كتابة البحث العلمي بالصورة الصحيحة وكيفية تلافي بعض الاخطاء التي يقع فيها بعض الباحثين اثناء كتابتهم للبحوث العلمية، وكذلك التسلسل العلمي الصحيح في كتابة فقرات البحث. وقد تطرقت الحلقة النقاشية ايضا الى الالية الصحيحة في ارسال البحث العلمي الى المجلات العلمية الرصينة وكيفية اختيار المجلة الملائمة لنشر هكذا بحوث علمية. ركز المعموري على اسرار ومفاتيح كتابة بحث علمي رصين وكيفية كتابته وماهي صيغة الكتابة وقواعدها، وكيفية مناقشة النتائج وكيفية اختيار المجلة المناسبة وماهي اجراءات التسليم وماهي عملية قبول او رفض البحث واسباب الرفض المحتملة.