Ehsan Ameen | Mustansiriyah University Iraq - Baghdad (original) (raw)
Papers by Ehsan Ameen
DOAJ (DOAJ: Directory of Open Access Journals), Mar 1, 2016
This study discusses the development of a multi-axial fatigue testing machine, and studies the fa... more This study discusses the development of a multi-axial fatigue testing machine, and studies the fatigue behavior of cantilever glass fiber composites beam under in phase bending-torsion dynamic loadings. The effect of bending–twisting deflections and the number of layers on the peak strength, fatigue life, and failure mechanisms are analyzed. Two types specimen (two dimension woven fiberglass (2D) and three dimension stitching fiberglass (3D)) are investigated. The results of both 2D and 3D show that the strength is increased significantly with increase bending-torsion stresses, while the damage becomes faster. The strength is reduced rapidly in about the first 30% of its fatigue life due to matrix cracking, which is then followed by a much slower rate of strength reduction until the failure. And the samples strength is increased as the number of layers increased by 20±3 % when tested under the same loading conditions. Furthermore the strength in 2D specimen is higher than the strength in the 3D specimen by about 20% when subjected to the same bending deflection-twisting angle. The fatigue life in 3D sample is greater than fatigue life in 2D samples by about 17% when tested under the same loading conditions.
Al-Qadisiyah University, 2013
Al-Mustansyriah University, 2007
In this work, the vibration characteristics of cantilever blades are studied; natural frequencies... more In this work, the vibration characteristics of cantilever blades are studied; natural frequencies are evaluated for different aspect ratios. Other parameters like thickness taper and width are considered. The experimental results are compared with numerical results using finite element method (ANSYS 5.4 package) these results give good agreement and show the effect of the aspect ratio on the natural frequency.
Journal of Engineering and Sustainable Development (JEASD), 2013
Studying for sound and noise is of great importance nowadays. And since the internal combustion e... more Studying for sound and noise is of great importance nowadays. And since the internal combustion engines are main sources of noise pollution, this study established to investigate the relationship between the acoustic powers immersed from two different electric generators and the applied variable loads. The engines are of single cylinder four stroke air cooled gasoline type engaged with electric generator heads. The results show an agreement with other works on other types of engines (diesel engines), and it is found that used generators make noise much more than factory specifications and this noise lower with load increment, in contrary in brand new generators noise grow with load increment.
Al-Qadisiyah Journal for Engineering Sciences, 2011
Journal of Engineering and Sustainable Development (JEASD), 2012
Journal of Engineering and Development, 2008
It is generally accepted that normal pressure beneath a track laying vehicle has great influence ... more It is generally accepted that normal pressure beneath a track laying vehicle has great influence on the slip and the tractive effort developed by the vehicle. However, and for simplicity, most of the previous works assume uniform pressure underneath the track. Consequently values of experimental results were quiet different from those of the predicted theoretical values. In this paper, emphasizes have been directed towards proper selection of vehicle configuration which is of almost importance. So, and as a result , different types of normal pressure underneath the track have been analyzed, ranging from constant , to uniform sinusoidal, and then to non uniform values. The magnitudes of drawbar pull for each type of pressure distribution on soft ground were evaluated theoretically with the aid of computer, using (''MATLAB'' package). The aim is to obtain the best value of draw-bar pull among these pressure distributions, thus achieving the optimum design criteria.
IOP material science and Engineering, 2020
This work is an experimental and numerical approach to analyze the effect of Nano powder additive... more This work is an experimental and numerical approach to analyze the effect of Nano powder additives and temperature on the critical crack length in fiber reinforced composite materials (FRC) exposed to uniaxial tensile load. Fiberglass/Epoxy compact tension test samples (CT) are prepared according to ASTM standard E399. Tio2 Nano powder is added by 2% wt to the resin to other samples. The static tensile test is applied to the samples and the results for crack length/time are discussed. ABAQUS/CAE software is used to simulate the case. The numerical and experimental results were close. The experimental results showed that the addition of 2%wt Tio2 Nano powder increased the critical crack length by 32.4%. the effect of ambient temperature is studied too by applying the experimental test on the fiberglass/Epoxy samples in room temperature (30˚C) once and at outdoor (60˚C) temperature. The results showed that the effect of the temperature increase decreased the critical crack length by 5...
Journal of Engineering and Sustainable Development
IOP Conference Series: Materials Science and Engineering
International Journal of Mechanical and Production Engineering Research and Development, 2018
This paper presents an experimental approach to analyze the strain due to internal pressure to th... more This paper presents an experimental approach to analyze the strain due to internal pressure to the effect of temperature in spherical pressure vessels made from composite materials. Laminates from different types of fibers (woven and random glass and woven Kevlar 29) are used as reinforcements in the polyester matrix. Different arrangements for fiber plies are used in fabricating half spherical shell closed from the bottom by a circular steel plate supported by a steel collar to hold out an internal pressure up to 100 bar. The applied pressure developed with an air compressor. An electric heater element is placed to heat the interior up to 70 ᵒ c. Some controlling equipment is used like pressure gages, heat sensors and strain gauges. It was found that locating of the strongest ply (Kevlar in this work) limits the hoop strain to its minimum values and that makes the vessel's exterior stable and settled on the structure without being affected by internal pressure or temperature. 12% reduction in hoop strain is established when the Kevlar ply placed in the outside ply instead of the middle ply at 70˚c and this ratio was 8% at 25˚c.
IOP Conference Series: Materials Science and Engineering
This work is an experimental and numerical approach to analyze the effect of Nano powder additive... more This work is an experimental and numerical approach to analyze the effect of Nano powder additives and temperature on the critical crack length in fiber reinforced composite materials (FRC) exposed to uniaxial tensile load. Fiberglass/Epoxy compact tension test samples (CT) are prepared according to ASTM standard E399. Tio2 Nano powder is added by 2% wt to the resin to other samples. The static tensile test is applied to the samples and the results for crack length/time are discussed. ABAQUS/CAE software is used to simulate the case. The numerical and experimental results were close. The experimental results showed that the addition of 2%wt Tio2 Nano powder increased the critical crack length by 32.4%. the effect of ambient temperature is studied too by applying the experimental test on the fiberglass/Epoxy samples in room temperature (30˚C) once and at outdoor (60˚C) temperature. The results showed that the effect of the temperature increase decreased the critical crack length by 51%. The numerical results determined the fracture toughness (KIC) for the fiberglass/Epoxy samples to be 491 pa.mm 0.5 and 517 pa.mm 0.5 for the fiberglass/Epoxy-Nano powder samples.
The mechanical properties of plain-woven natural fiber-reinforced composites (NFRC) were investig... more The mechanical properties of plain-woven natural fiber-reinforced composites (NFRC) were investigated in the present study. Three types of natural fibers, Cotton, Kenaf, and Wool, were used as reinforcements for Epoxy-based overlaid composites. The properties E-type fiberglass/Epoxy composite were brought to comparison with the features of NFRC's. The mechanical properties of samples exposed to tensile, shear, and flexural loadings were obtained. The results showed that the ratio of the specific tensile strength of the cotton/epoxy laminates to laminates, which reinforced with kenaf or wool fibers were 1.71 and 4.47, respectively. Under shear loadings, the specific strength of the cotton fiber samples was also 1.24 and 2.45 times greater than kenaf and wool fiber samples, respectively. The particular flexural strength of the cotton/epoxy samples were 1.42 and 2.34 times greater than kenaf/epoxy and wool/epoxy composites. As a comparison for specific energy absorption between cotton/epoxy samples and glass fiber reinforced specimens under tensile loading, the cotton samples were 2.7 times greater than that of the glass samples. The work also included measurements of the amount of water absorption by different examples, moisture absorption tests were carried out in intervals of 3 and 10 days. The results showed that the most significant percent of the water absorption, which is (7.47%) was related to the cotton reinforced specimens at an interval of 10 days.
2ND INTERNATIONAL CONFERENCE ON MATERIALS ENGINEERING & SCIENCE (IConMEAS 2019)
DOAJ (DOAJ: Directory of Open Access Journals), Mar 1, 2016
This study discusses the development of a multi-axial fatigue testing machine, and studies the fa... more This study discusses the development of a multi-axial fatigue testing machine, and studies the fatigue behavior of cantilever glass fiber composites beam under in phase bending-torsion dynamic loadings. The effect of bending–twisting deflections and the number of layers on the peak strength, fatigue life, and failure mechanisms are analyzed. Two types specimen (two dimension woven fiberglass (2D) and three dimension stitching fiberglass (3D)) are investigated. The results of both 2D and 3D show that the strength is increased significantly with increase bending-torsion stresses, while the damage becomes faster. The strength is reduced rapidly in about the first 30% of its fatigue life due to matrix cracking, which is then followed by a much slower rate of strength reduction until the failure. And the samples strength is increased as the number of layers increased by 20±3 % when tested under the same loading conditions. Furthermore the strength in 2D specimen is higher than the strength in the 3D specimen by about 20% when subjected to the same bending deflection-twisting angle. The fatigue life in 3D sample is greater than fatigue life in 2D samples by about 17% when tested under the same loading conditions.
Al-Qadisiyah University, 2013
Al-Mustansyriah University, 2007
In this work, the vibration characteristics of cantilever blades are studied; natural frequencies... more In this work, the vibration characteristics of cantilever blades are studied; natural frequencies are evaluated for different aspect ratios. Other parameters like thickness taper and width are considered. The experimental results are compared with numerical results using finite element method (ANSYS 5.4 package) these results give good agreement and show the effect of the aspect ratio on the natural frequency.
Journal of Engineering and Sustainable Development (JEASD), 2013
Studying for sound and noise is of great importance nowadays. And since the internal combustion e... more Studying for sound and noise is of great importance nowadays. And since the internal combustion engines are main sources of noise pollution, this study established to investigate the relationship between the acoustic powers immersed from two different electric generators and the applied variable loads. The engines are of single cylinder four stroke air cooled gasoline type engaged with electric generator heads. The results show an agreement with other works on other types of engines (diesel engines), and it is found that used generators make noise much more than factory specifications and this noise lower with load increment, in contrary in brand new generators noise grow with load increment.
Al-Qadisiyah Journal for Engineering Sciences, 2011
Journal of Engineering and Sustainable Development (JEASD), 2012
Journal of Engineering and Development, 2008
It is generally accepted that normal pressure beneath a track laying vehicle has great influence ... more It is generally accepted that normal pressure beneath a track laying vehicle has great influence on the slip and the tractive effort developed by the vehicle. However, and for simplicity, most of the previous works assume uniform pressure underneath the track. Consequently values of experimental results were quiet different from those of the predicted theoretical values. In this paper, emphasizes have been directed towards proper selection of vehicle configuration which is of almost importance. So, and as a result , different types of normal pressure underneath the track have been analyzed, ranging from constant , to uniform sinusoidal, and then to non uniform values. The magnitudes of drawbar pull for each type of pressure distribution on soft ground were evaluated theoretically with the aid of computer, using (''MATLAB'' package). The aim is to obtain the best value of draw-bar pull among these pressure distributions, thus achieving the optimum design criteria.
IOP material science and Engineering, 2020
This work is an experimental and numerical approach to analyze the effect of Nano powder additive... more This work is an experimental and numerical approach to analyze the effect of Nano powder additives and temperature on the critical crack length in fiber reinforced composite materials (FRC) exposed to uniaxial tensile load. Fiberglass/Epoxy compact tension test samples (CT) are prepared according to ASTM standard E399. Tio2 Nano powder is added by 2% wt to the resin to other samples. The static tensile test is applied to the samples and the results for crack length/time are discussed. ABAQUS/CAE software is used to simulate the case. The numerical and experimental results were close. The experimental results showed that the addition of 2%wt Tio2 Nano powder increased the critical crack length by 32.4%. the effect of ambient temperature is studied too by applying the experimental test on the fiberglass/Epoxy samples in room temperature (30˚C) once and at outdoor (60˚C) temperature. The results showed that the effect of the temperature increase decreased the critical crack length by 5...
Journal of Engineering and Sustainable Development
IOP Conference Series: Materials Science and Engineering
International Journal of Mechanical and Production Engineering Research and Development, 2018
This paper presents an experimental approach to analyze the strain due to internal pressure to th... more This paper presents an experimental approach to analyze the strain due to internal pressure to the effect of temperature in spherical pressure vessels made from composite materials. Laminates from different types of fibers (woven and random glass and woven Kevlar 29) are used as reinforcements in the polyester matrix. Different arrangements for fiber plies are used in fabricating half spherical shell closed from the bottom by a circular steel plate supported by a steel collar to hold out an internal pressure up to 100 bar. The applied pressure developed with an air compressor. An electric heater element is placed to heat the interior up to 70 ᵒ c. Some controlling equipment is used like pressure gages, heat sensors and strain gauges. It was found that locating of the strongest ply (Kevlar in this work) limits the hoop strain to its minimum values and that makes the vessel's exterior stable and settled on the structure without being affected by internal pressure or temperature. 12% reduction in hoop strain is established when the Kevlar ply placed in the outside ply instead of the middle ply at 70˚c and this ratio was 8% at 25˚c.
IOP Conference Series: Materials Science and Engineering
This work is an experimental and numerical approach to analyze the effect of Nano powder additive... more This work is an experimental and numerical approach to analyze the effect of Nano powder additives and temperature on the critical crack length in fiber reinforced composite materials (FRC) exposed to uniaxial tensile load. Fiberglass/Epoxy compact tension test samples (CT) are prepared according to ASTM standard E399. Tio2 Nano powder is added by 2% wt to the resin to other samples. The static tensile test is applied to the samples and the results for crack length/time are discussed. ABAQUS/CAE software is used to simulate the case. The numerical and experimental results were close. The experimental results showed that the addition of 2%wt Tio2 Nano powder increased the critical crack length by 32.4%. the effect of ambient temperature is studied too by applying the experimental test on the fiberglass/Epoxy samples in room temperature (30˚C) once and at outdoor (60˚C) temperature. The results showed that the effect of the temperature increase decreased the critical crack length by 51%. The numerical results determined the fracture toughness (KIC) for the fiberglass/Epoxy samples to be 491 pa.mm 0.5 and 517 pa.mm 0.5 for the fiberglass/Epoxy-Nano powder samples.
The mechanical properties of plain-woven natural fiber-reinforced composites (NFRC) were investig... more The mechanical properties of plain-woven natural fiber-reinforced composites (NFRC) were investigated in the present study. Three types of natural fibers, Cotton, Kenaf, and Wool, were used as reinforcements for Epoxy-based overlaid composites. The properties E-type fiberglass/Epoxy composite were brought to comparison with the features of NFRC's. The mechanical properties of samples exposed to tensile, shear, and flexural loadings were obtained. The results showed that the ratio of the specific tensile strength of the cotton/epoxy laminates to laminates, which reinforced with kenaf or wool fibers were 1.71 and 4.47, respectively. Under shear loadings, the specific strength of the cotton fiber samples was also 1.24 and 2.45 times greater than kenaf and wool fiber samples, respectively. The particular flexural strength of the cotton/epoxy samples were 1.42 and 2.34 times greater than kenaf/epoxy and wool/epoxy composites. As a comparison for specific energy absorption between cotton/epoxy samples and glass fiber reinforced specimens under tensile loading, the cotton samples were 2.7 times greater than that of the glass samples. The work also included measurements of the amount of water absorption by different examples, moisture absorption tests were carried out in intervals of 3 and 10 days. The results showed that the most significant percent of the water absorption, which is (7.47%) was related to the cotton reinforced specimens at an interval of 10 days.
2ND INTERNATIONAL CONFERENCE ON MATERIALS ENGINEERING & SCIENCE (IConMEAS 2019)