The turbulent heat transfer and friction inside a corrugated square duct inserted with various ba... more The turbulent heat transfer and friction inside a corrugated square duct inserted with various baffles geometries have been studied experimentally. Five types of baffles (flat, rectangular, semicircular, triangular and trapezoidal) are attached on top and bottom walls of the duct. The effects of duct wavy surface, baffle geometry, baffle position and flow Reynolds number are examined. Air is used as the working fluid with Reynolds number ranged from 3442.6 to 17213.19 under constant wall heat flux. Experimental results show obtained for average Nusselt numbers and friction factor. The results indicate that the trapezoidal baffled geometry provides a higher thermal performance than the other type baffled one. The present work showed that the highest thermal performance factor under the same pumping power obtained from the experiments, is about 2.26 times more than that of plain duct. Also, it is found that the thermal performance of the baffles attach on the bottom wall of the duct i...
ABSTRACT: Nowadays, waste disposal, is one of the most important environmental problems. Since th... more ABSTRACT: Nowadays, waste disposal, is one of the most important environmental problems. Since the usage of composite materials has put down all areas of industry, recycling processes of composite materials have been becoming of keen interest. As is known, composites are divided into two primary groups: thermoplastic and thermoset materials. The thermoplastics are easily managed with conventional methods of recycling, while it is difficult to do so in the thermoset ones. In this work, glass fiber reinforced polyester (GFRP) particles of waste materials are mixed with pure polyester by certain mass fractions and various particle sizes. The mechanical properties (Elastic modulus and strength) are investigated using tensile and compression tests. It was found that mixing GFRP smashed particles of (2.36mm) size by 10% of its weight with pure polyester increases the modulus of elasticity by 100% compared with the pure polyester keeping the value of failure stress for both tensile and com...
IOP Conference Series: Materials Science and Engineering, 2020
In the manufacturing field of industrial firms, some materials are hard to cut and do not meet th... more In the manufacturing field of industrial firms, some materials are hard to cut and do not meet the mechanical operation requirements in conventional and unconventional machining methods due to their high mechanical properties which poorer their machinability. The need is ongoing and growing to these materials in important industries, therefore hot machining is considered one of the most advanced methods of machining which help to solve the problem of these materials. This process involves heating the work piece at elevated temperature during or before machining on conventional cutting machine by using various external heating techniques, which soften it and becomes more ductile and this leads to improve the machinability. This paper displays a review on hot machining process and presents its effectiveness for the industrial firm in machining hard-to cut-materials which reflect on cost and productivity in relation to other aspects of machining. The review paper presents a survey on v...
The turbulent heat transfer and friction inside a corrugated square duct inserted with various ba... more The turbulent heat transfer and friction inside a corrugated square duct inserted with various baffles geometries have been studied experimentally. Five types of baffles (flat, rectangular, semicircular, triangular and trapezoidal) are attached on top and bottom walls of the duct. The effects of duct wavy surface, baffle geometry, baffle position and flow Reynolds number are examined. Air is used as the working fluid with Reynolds number ranged from 3442.6 to 17213.19 under constant wall heat flux. Experimental results show obtained for average Nusselt numbers and friction factor. The results indicate that the trapezoidal baffled geometry provides a higher thermal performance than the other type baffled one. The present work showed that the highest thermal performance factor under the same pumping power obtained from the experiments, is about 2.26 times more than that of plain duct. Also, it is found that the thermal performance of the baffles attach on the bottom wall of the duct i...
ABSTRACT: Nowadays, waste disposal, is one of the most important environmental problems. Since th... more ABSTRACT: Nowadays, waste disposal, is one of the most important environmental problems. Since the usage of composite materials has put down all areas of industry, recycling processes of composite materials have been becoming of keen interest. As is known, composites are divided into two primary groups: thermoplastic and thermoset materials. The thermoplastics are easily managed with conventional methods of recycling, while it is difficult to do so in the thermoset ones. In this work, glass fiber reinforced polyester (GFRP) particles of waste materials are mixed with pure polyester by certain mass fractions and various particle sizes. The mechanical properties (Elastic modulus and strength) are investigated using tensile and compression tests. It was found that mixing GFRP smashed particles of (2.36mm) size by 10% of its weight with pure polyester increases the modulus of elasticity by 100% compared with the pure polyester keeping the value of failure stress for both tensile and com...
IOP Conference Series: Materials Science and Engineering, 2020
In the manufacturing field of industrial firms, some materials are hard to cut and do not meet th... more In the manufacturing field of industrial firms, some materials are hard to cut and do not meet the mechanical operation requirements in conventional and unconventional machining methods due to their high mechanical properties which poorer their machinability. The need is ongoing and growing to these materials in important industries, therefore hot machining is considered one of the most advanced methods of machining which help to solve the problem of these materials. This process involves heating the work piece at elevated temperature during or before machining on conventional cutting machine by using various external heating techniques, which soften it and becomes more ductile and this leads to improve the machinability. This paper displays a review on hot machining process and presents its effectiveness for the industrial firm in machining hard-to cut-materials which reflect on cost and productivity in relation to other aspects of machining. The review paper presents a survey on v...
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Papers by Dr. Jaafar Jaber