djamal didane - Academia.edu (original) (raw)

Papers by djamal didane

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences

The drone becomes more recognized in the civilian sector; the drone's popularity becomes incr... more The drone becomes more recognized in the civilian sector; the drone's popularity becomes increases as time goes by. Nevertheless, despite the excitement of flying drones, several types of issues occur caused by the drone. In some circumstances, the aeroacoustics noise is a big concern, and quiet drone propellers would be more environmentally friendly to the surrounding area. Moreover, the noise from the drone can be a nuisance for the surrounding population and animals. Therefore, a solution needs to be proposed to reduce the sound level produced by the drone so that drone can be piloted in a surrounding area without breaking any noise level limit set by the government. Hence, the propeller's serrated trailing edge type is the proposed solution to this problem. The serrated trailing edge propeller can reduce several drone noise decibels based on past research. Thus, an investigation is conducted to study the thrust force between the normal propeller and the serrated propelle...

Journal of Applied Engineering Science

Due to technological advancements and environmental concerns, wind power generation using wind tu... more Due to technological advancements and environmental concerns, wind power generation using wind turbines has increased significantly in recent years. In the current study, meteorological data over five years (2015 - 2019) have been used in order to estimate the Weibull distribution function, wind power, and energy density for ten meteorological stations in three provinces. Monthly and yearly wind speed variations are analyzed. The results demonstrated that the values of the shape and scale parameters are varied over a wide range for each site. Moreover, the results illustrated that the highest wind power potential occurs at Jayawijaya city with a potential of 36.23 w/m2. On the other hand, results showed that the monthly wind speed varies in a large range in each site. In the Jayawijaya city, for example, it ranged between 2.27 and 2.9 m/s, whereas in the Bogor Regency it ranged between 0.58 and 0.25 m/s. According to the predicted yearly power and energy densities, the evaluated sit...

International Journal of Renewable Energy Development

The production of metal matrix composites (MMCs) through recycled materials is a cost-saving proc... more The production of metal matrix composites (MMCs) through recycled materials is a cost-saving process. However, the improvement of the mechanical and physical properties is another challenge to be concerned. In this study, recycled aluminium 6061 (AA6061) chips reinforced with different volumetric fractions of boron carbide (B4C) were produced through hot equal channel angular processing (ECAP). Response surface methodology (RSM) was carried out to investigate the dependent response (compressive strength) with independent parameters such as different volumetric fractions (5-15%) of added contents of B4C and preheating temperature (450 – 550°C). Also, the number of passes were examined to check the effect on the mechanical and physical properties of the developed recycled AA6061/B4C composite. The results show that maximum compressive strength and hardness of recycled AA6061/B4C were 59.2 MPa and 69 HV respectively at 5% of B4C contents. Likewise, the density and number of pores incr...

Renewable energies are the types of energy that always exist and environmentally friendly. Wind e... more Renewable energies are the types of energy that always exist and environmentally friendly. Wind energy is one of the renewable energy types that can reduce the mass use of fossil fuels as an alternative way to generate electricity. Practically, the Wind turbine is responsible for converting the kinetic energy as the wind act on the blades to generate electrical energy. In this study, the Savonius-type counter-rotating wind turbine has been chosen to study its aerodynamic performance on a moving train. For the simulation, the wind velocities tested start from 50 km/h until 160 km/h with 10 km/h interval between each case while investigating the performance in terms of torque and power output. The designs of the models are developed using Solidworks software and the Computational Fluid Dynamics (CFD) simulation software; ANSYS FLUENT was sued to run the simulations. The simulation results such as velocity streamlines, velocity contours, pressure contours and turbulent kinetic energy h...

4 Automotive and Combustion Synergies Technology Group, Faculty of Engineering Technology, Univer... more 4 Automotive and Combustion Synergies Technology Group, Faculty of Engineering Technology, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia Department of Marine Engineering, Politeknik Bagan Datuk, 36400, Perak, Malaysia Centre for Diploma Studies, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia

Sustainable Energy Technologies and Assessments, 2021

Abstract Savonius wind turbine is an interesting type of vertical axis wind turbines (VAWTs) whic... more Abstract Savonius wind turbine is an interesting type of vertical axis wind turbines (VAWTs) which has a low cost of manufacturing, however, this turbine has a relatively low power output compared to the other types of VAWTs. Further study is required to enhance its performance to match the high demand of the power generation in small-scale applications. The main objective of the current study is to enhance the power output coefficient (Cp) of the conventional Savonius rotor by adding two-inner blades to the geometry. The performance assessment was performed for five different angles of inner blades (100°, 120°, 140°, 160°, and 180°). Moreover, the effect of spacing between inner blades was numerically examined for three values of spacing i.e. 0.02, 0.01, and 0.005 m. The current two-dimensional simulation was performed utilizing the Ansys Fluent solver. The simulation results affirmed that the maximum enhancement to be 32.9% compared to the conventional rotor at TSR equal to 0.7 when the spacing between inner blades is 0.005 m with an inner blades angle of 100°. Moreover, results demonstrated that the Ct max is 0.435 at TSR = 0.4 for the rotor with 160° inner blades and a spacing of 0.005 m.

Evergreen, 2021

This study presents an analysis of wind power potentials for two meteorological stations in the e... more This study presents an analysis of wind power potentials for two meteorological stations in the eastern part of Malaysia using the statistical Weibull distribution method over a period of ten years stretching from 2010 to 2019. As the estimation of the resource potentials is crucial towards the planning of a wind energy project, the primary objective of this study is to reveal the characteristics and potentials of the two selected sites. The results show that the highest annual average wind speed was 3.4 m/s at Kudat station and 2.3 m/s at Santubong station. The maximum shape and scale parameters were respectively 1.68 and 2.88 m/s and both appeared at Kudat station. The wind power density ranged between 9.45 W/m 2 and 24.24 W/m 2. The maximum energy density at Kudat was 207.60 kWh/m 2 /year and 106.01 kWh/m 2 /year at Santubong. The most probable wind speeds and wind carrying maximum energy were predicted at 1.68 m/s and 4.59 m/s and both speeds were observed at Kudat in 2019. The maximum deviation between observed frequencies and Weibull frequency distributions was around 27%. While the wind power at each site differs considerably, both of these two stations fall outside of the category of pacific northwest national laboratory (PNNL) classifications due to their low mean wind speeds. Nevertheless, it can be categorized for a smaller scale of wind power generation at a wind turbine elevation of more than 10 m.

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2021

Thermal fluids modulate temperature conditions around the thermal collector systems indirectly by... more Thermal fluids modulate temperature conditions around the thermal collector systems indirectly by circulating the heat transfer fluid throughout the heat exchanger, thereby simulating cooling and heating with thermal condition. This study investigates biofluid from Moringa oleifera kernel, Date kernel, Palm kernel, Coconut kernel and Mango kernel as base fluids for heat transfer fluid application in solar thermal technology. The methodology employed in this study is experimental and the analyzed biofluids results was compared with conventional heat transfer base fluids. Thermal constant analyzer (TPS-2005S), CT-72 Transparent viscometer and Eagle eye SG-500 portable digital hydrometer were used to measure the thermophysical properties, viscosity, and density, of the biofluids respectfully. From the results, the biofluids showed comparative thermophysical properties to conventional base fluids. Moringa oleifera kernel oil and Mango kernel oil has the best quality among the biofluids ...

1 Department of Aeronautical Engineering, Faculty of Mechanical and Manufacturing Engineering, Un... more 1 Department of Aeronautical Engineering, Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Johor, Malaysia 2 Department of Energy and Thermofluid Engineering, Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Johor, Malaysia 3 Department of Renewable Energy Engineering, Faculty of Engineering, Al-Isra University, Amman-Jordan

Wind energy is being considered all over the world due to the clean characteristics that it posse... more Wind energy is being considered all over the world due to the clean characteristics that it possesses and prevalent virtually everywhere in the world. With the current existing technology, a wind turbine could only harness a small portion of energy from the available wind. The amount of harnessed energy could be significantly decreased, if proper wind energy assessments (i.e. micrositing, geographical condition, wind regime characteristics, etc.) were not performed carefully and effectively. As previous studies have shown that, most of the projects which seem to be unfeasible were due to environmental problems such as appropriate site selection, and not technological problems such as wind turbine design. This study presents and discusses the main factors to be considered when undertaking wind energy project in any potential site, so that significant amount of energy could be harvested.

IOP Conference Series: Materials Science and Engineering, 2021

The consumption of electricity at highways is increasing over time, consequently, more fossil fue... more The consumption of electricity at highways is increasing over time, consequently, more fossil fuel is burned to generate more electrical energy. However, this expensive cost of burning fossil fuels can be saved by replacing them with renewable energy sources such as wind energy. Wind energy can be generated by using a wind turbine. Therefore, this study aims to develop a vertical axis wind turbine (VAWT) that can work effectively in highway wind speed conditions while evaluating its performance in terms of torque and power by using a simulation approach. The simulation involves the use of K-omega shear-stress transport (SST) as the turbulence viscosity model. The VAWT undergoes two types of tests during the simulation process. In Test 1, the wind turbine is tested with a various number of blades at constant wind speed to find which model has the best performance in terms of torque and power output. Then, the selected model with the better output proceeds to Test 2 where it is tested...

This study presents an overview on the possibilities of interior noise reduction for monorail sys... more This study presents an overview on the possibilities of interior noise reduction for monorail system using passive means. Nine samples out of three materials were subjected for noise test and the performance of each sample was observed. It is found that all of these samples have proved to reduce a significant amount noise at low and high frequencies even though the amount reduced differ from one sample to another. It is also been noticed that this reductions were denominated by means of absorption for some samples such as those from rubber material, and it was dominated by means of reflection for some others such as those from aluminum composite and paper composite. Moreover, from these different acoustic properties of each material, the whereabouts to install every material is different as well. It was suggested that, the rubber material should be installed on the upper floor of the monorail while, the paper composite should be installed under floor, and the aluminum composite shou...

Applied Mechanics and Materials, 2015

Numerical study using ANSYS Fluent is conducted to investigate the effects of louver angle on pre... more Numerical study using ANSYS Fluent is conducted to investigate the effects of louver angle on pressure drop and heat transfer of a heat exchanger. Flow simulations are conducted on 3D modeling of multi stacks louvered fins at three different parameters of louver angles which are 22.0o, 25.5o and 29.0o with Reynolds number ranging from 200 to 1000. These Reynolds numbers are based on louver pitch and fin pitch. The flow temperature is set at 300K which is the room temperature, while temperature of louver fin is set at 400K. The results show that Reynolds number based on fin pitch 2.02 mm and louver angle of 22.0o generate higher performance of heat exchanger compared to louver pitch of 1.40 mm and the other louver angles. Therefore, configuration of Reynolds number based on fin pitch 2.02 mm and louver angle 22.0o is preferred to be adopted in the design process of heat exchanger.

Applied Mechanics and Materials, 2013

This paper presents the effect of the changes in fin geometry on pressure drop and heat transfer ... more This paper presents the effect of the changes in fin geometry on pressure drop and heat transfer characteristics of louvered fin heat exchanger numerically. Three dimensional simulation using ANSYS Fluent have been conducted for six different configurations at Reynolds number ranging from 200 to 1000 based on louver pitch. The performance of this system has been evaluated by calculating pressure drop and heat transfer coefficient. The result shows that, the fin pitch and the louver pitch have a very considerable effect on pressure drop as well as heat transfer rate. It is observed that increasing the fin pitch will relatively result in an increase in heat transfer rate but at the same time, the pressure drop will decrease. On the other hand, low pressure drop and low heat transfer rate will be obtained when the louver pitch is increased. Final result shows a good agreement between experimental and numerical results of the louvered fin which is about 12%. This indicates the capabilit...

CFD Letters

The Savonius wind turbine is considered as one of the solutions for harvesting the kinetic energy... more The Savonius wind turbine is considered as one of the solutions for harvesting the kinetic energy from the wind in the urban areas, due to magnificent features such as, low construction cost, high starting torque, and self-starting ability especially at low wind speed. However, the conventional rotor suffers from low efficiency. Thus, modifying the configuration of the rotor may be an effective solution for providing electricity to the communities with no access to the power grid. Thus, this investigation aims to study numerically the effect of adding two inner blades on the performance of the Savonius wind rotor at low tip speed ratios (TSRs). The simulations are carried out using the two-dimensional simulation with the assist of ANSYS software. For turbulence modelling, the K-ε/realizable model was adopted in this study. Power coefficient (C p) and torque coefficient (C t) at various TSRs for the rotor are determined under a constant external overlap of 0.018 m. Furthermore, the effect of space between the inner blades was also investigated using three values of spacing. The simulation results show that the rotor with two inner blades performs better than the same rotor without inner blades at all tested TSRs expect at low considered values of 0.2 and 0.25. The heights Cp was 0.188 with 17.1% performance improvement at TSR = 0.4. Furthermore, the numerical results show that C p values decrease with the decrease of the space between the blades.

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences

The use of solar thermal technologies has shown great prospects towards solar energy conversion i... more The use of solar thermal technologies has shown great prospects towards solar energy conversion into more useful forms of energy and has increasingly expanded solar thermal technology applications. However, the inability to properly store the excess solar energies during peak hours and demands have limited many of their applications. The integration of thermal energy storage (TES) systems with thermal technologies have increased the solar thermal technology performance but the poor thermal characteristics exhibited by phase change materials (PCM) limited the system overall performance. The enhancement of PCM properties by nonadditive have shown increased material performance in TES application and thereby extending the use of solar thermal technology application. Given this narrative and identifies literature gaps, the present study investigated experimentally the enhancement of paraffin PCM using nonadditive metallic of different types and concentrations and analysed their thermal ...

International Journal of Integrated Engineering

Fluids

The present paper aims to study the possibility of dispensing an auxiliary power unit (APU) in an... more The present paper aims to study the possibility of dispensing an auxiliary power unit (APU) in an aircraft powered by fossil fuels to reduce air pollution. It particularly seeks to evaluate the amount of power generated by the ram air turbine (RAT) using the novel counter-rotating technique while characterizing its optimum axial distance. The ram air turbine (RAT), which is already equipped in aircrafts, was enhanced to generate the amount of energy produced by the APU. The approach was implemented by a CRRAT system. Six airfoil profiles were tested based on 2D models and the best airfoil was chosen for implantation on the RAT and CRRAT systems. The performance of the conventional single-rotor RAT and CRRAT were analyzed using FLUENT software based on 3D models. The adopted numerical scheme was the Navier–Stokes equation with k–ω SST turbulence modeling. The dynamic mesh and user-defined function (UDF) were used to revolve the rotor turbine via wind. The results indicated that the F...

The International Journal of Integrated Engineering

Wind power is sustainable and prevalent virtually all over the globe. However, the conversion eff... more Wind power is sustainable and prevalent virtually all over the globe. However, the conversion efficiency of the conventional single-rotor wind turbine (SRWT) is still far from satisfactory. The dual-rotor counter-rotating concept is among the reliable techniques used to enhance the efficiency of a wind energy conversion device for its renowned effectiveness. This study aims to investigate the performance of a Savonius dual/twin-rotor system, particularly in low-speed wind conditions while employing the counter-rotating technique. The evaluation of this technique is presented in terms of aerodynamic characteristics, including the power and torque coefficients. The results have shown that the new concept was able to improve the performance of the system extensively and was capable of operating in a lower wind speed condition. Compared to a single-rotor system, an additional 42% more torque was possible owing to the existence of a second rotor in the new system. The results have also r...

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences

The drone becomes more recognized in the civilian sector; the drone's popularity becomes incr... more The drone becomes more recognized in the civilian sector; the drone's popularity becomes increases as time goes by. Nevertheless, despite the excitement of flying drones, several types of issues occur caused by the drone. In some circumstances, the aeroacoustics noise is a big concern, and quiet drone propellers would be more environmentally friendly to the surrounding area. Moreover, the noise from the drone can be a nuisance for the surrounding population and animals. Therefore, a solution needs to be proposed to reduce the sound level produced by the drone so that drone can be piloted in a surrounding area without breaking any noise level limit set by the government. Hence, the propeller's serrated trailing edge type is the proposed solution to this problem. The serrated trailing edge propeller can reduce several drone noise decibels based on past research. Thus, an investigation is conducted to study the thrust force between the normal propeller and the serrated propelle...

Journal of Applied Engineering Science

Due to technological advancements and environmental concerns, wind power generation using wind tu... more Due to technological advancements and environmental concerns, wind power generation using wind turbines has increased significantly in recent years. In the current study, meteorological data over five years (2015 - 2019) have been used in order to estimate the Weibull distribution function, wind power, and energy density for ten meteorological stations in three provinces. Monthly and yearly wind speed variations are analyzed. The results demonstrated that the values of the shape and scale parameters are varied over a wide range for each site. Moreover, the results illustrated that the highest wind power potential occurs at Jayawijaya city with a potential of 36.23 w/m2. On the other hand, results showed that the monthly wind speed varies in a large range in each site. In the Jayawijaya city, for example, it ranged between 2.27 and 2.9 m/s, whereas in the Bogor Regency it ranged between 0.58 and 0.25 m/s. According to the predicted yearly power and energy densities, the evaluated sit...

International Journal of Renewable Energy Development

The production of metal matrix composites (MMCs) through recycled materials is a cost-saving proc... more The production of metal matrix composites (MMCs) through recycled materials is a cost-saving process. However, the improvement of the mechanical and physical properties is another challenge to be concerned. In this study, recycled aluminium 6061 (AA6061) chips reinforced with different volumetric fractions of boron carbide (B4C) were produced through hot equal channel angular processing (ECAP). Response surface methodology (RSM) was carried out to investigate the dependent response (compressive strength) with independent parameters such as different volumetric fractions (5-15%) of added contents of B4C and preheating temperature (450 – 550°C). Also, the number of passes were examined to check the effect on the mechanical and physical properties of the developed recycled AA6061/B4C composite. The results show that maximum compressive strength and hardness of recycled AA6061/B4C were 59.2 MPa and 69 HV respectively at 5% of B4C contents. Likewise, the density and number of pores incr...

Renewable energies are the types of energy that always exist and environmentally friendly. Wind e... more Renewable energies are the types of energy that always exist and environmentally friendly. Wind energy is one of the renewable energy types that can reduce the mass use of fossil fuels as an alternative way to generate electricity. Practically, the Wind turbine is responsible for converting the kinetic energy as the wind act on the blades to generate electrical energy. In this study, the Savonius-type counter-rotating wind turbine has been chosen to study its aerodynamic performance on a moving train. For the simulation, the wind velocities tested start from 50 km/h until 160 km/h with 10 km/h interval between each case while investigating the performance in terms of torque and power output. The designs of the models are developed using Solidworks software and the Computational Fluid Dynamics (CFD) simulation software; ANSYS FLUENT was sued to run the simulations. The simulation results such as velocity streamlines, velocity contours, pressure contours and turbulent kinetic energy h...

4 Automotive and Combustion Synergies Technology Group, Faculty of Engineering Technology, Univer... more 4 Automotive and Combustion Synergies Technology Group, Faculty of Engineering Technology, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia Department of Marine Engineering, Politeknik Bagan Datuk, 36400, Perak, Malaysia Centre for Diploma Studies, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia, Johor, Malaysia

Sustainable Energy Technologies and Assessments, 2021

Abstract Savonius wind turbine is an interesting type of vertical axis wind turbines (VAWTs) whic... more Abstract Savonius wind turbine is an interesting type of vertical axis wind turbines (VAWTs) which has a low cost of manufacturing, however, this turbine has a relatively low power output compared to the other types of VAWTs. Further study is required to enhance its performance to match the high demand of the power generation in small-scale applications. The main objective of the current study is to enhance the power output coefficient (Cp) of the conventional Savonius rotor by adding two-inner blades to the geometry. The performance assessment was performed for five different angles of inner blades (100°, 120°, 140°, 160°, and 180°). Moreover, the effect of spacing between inner blades was numerically examined for three values of spacing i.e. 0.02, 0.01, and 0.005 m. The current two-dimensional simulation was performed utilizing the Ansys Fluent solver. The simulation results affirmed that the maximum enhancement to be 32.9% compared to the conventional rotor at TSR equal to 0.7 when the spacing between inner blades is 0.005 m with an inner blades angle of 100°. Moreover, results demonstrated that the Ct max is 0.435 at TSR = 0.4 for the rotor with 160° inner blades and a spacing of 0.005 m.

Evergreen, 2021

This study presents an analysis of wind power potentials for two meteorological stations in the e... more This study presents an analysis of wind power potentials for two meteorological stations in the eastern part of Malaysia using the statistical Weibull distribution method over a period of ten years stretching from 2010 to 2019. As the estimation of the resource potentials is crucial towards the planning of a wind energy project, the primary objective of this study is to reveal the characteristics and potentials of the two selected sites. The results show that the highest annual average wind speed was 3.4 m/s at Kudat station and 2.3 m/s at Santubong station. The maximum shape and scale parameters were respectively 1.68 and 2.88 m/s and both appeared at Kudat station. The wind power density ranged between 9.45 W/m 2 and 24.24 W/m 2. The maximum energy density at Kudat was 207.60 kWh/m 2 /year and 106.01 kWh/m 2 /year at Santubong. The most probable wind speeds and wind carrying maximum energy were predicted at 1.68 m/s and 4.59 m/s and both speeds were observed at Kudat in 2019. The maximum deviation between observed frequencies and Weibull frequency distributions was around 27%. While the wind power at each site differs considerably, both of these two stations fall outside of the category of pacific northwest national laboratory (PNNL) classifications due to their low mean wind speeds. Nevertheless, it can be categorized for a smaller scale of wind power generation at a wind turbine elevation of more than 10 m.

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2021

Thermal fluids modulate temperature conditions around the thermal collector systems indirectly by... more Thermal fluids modulate temperature conditions around the thermal collector systems indirectly by circulating the heat transfer fluid throughout the heat exchanger, thereby simulating cooling and heating with thermal condition. This study investigates biofluid from Moringa oleifera kernel, Date kernel, Palm kernel, Coconut kernel and Mango kernel as base fluids for heat transfer fluid application in solar thermal technology. The methodology employed in this study is experimental and the analyzed biofluids results was compared with conventional heat transfer base fluids. Thermal constant analyzer (TPS-2005S), CT-72 Transparent viscometer and Eagle eye SG-500 portable digital hydrometer were used to measure the thermophysical properties, viscosity, and density, of the biofluids respectfully. From the results, the biofluids showed comparative thermophysical properties to conventional base fluids. Moringa oleifera kernel oil and Mango kernel oil has the best quality among the biofluids ...

1 Department of Aeronautical Engineering, Faculty of Mechanical and Manufacturing Engineering, Un... more 1 Department of Aeronautical Engineering, Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Johor, Malaysia 2 Department of Energy and Thermofluid Engineering, Faculty of Mechanical and Manufacturing Engineering, Universiti Tun Hussein Onn Malaysia (UTHM), Johor, Malaysia 3 Department of Renewable Energy Engineering, Faculty of Engineering, Al-Isra University, Amman-Jordan

Wind energy is being considered all over the world due to the clean characteristics that it posse... more Wind energy is being considered all over the world due to the clean characteristics that it possesses and prevalent virtually everywhere in the world. With the current existing technology, a wind turbine could only harness a small portion of energy from the available wind. The amount of harnessed energy could be significantly decreased, if proper wind energy assessments (i.e. micrositing, geographical condition, wind regime characteristics, etc.) were not performed carefully and effectively. As previous studies have shown that, most of the projects which seem to be unfeasible were due to environmental problems such as appropriate site selection, and not technological problems such as wind turbine design. This study presents and discusses the main factors to be considered when undertaking wind energy project in any potential site, so that significant amount of energy could be harvested.

IOP Conference Series: Materials Science and Engineering, 2021

The consumption of electricity at highways is increasing over time, consequently, more fossil fue... more The consumption of electricity at highways is increasing over time, consequently, more fossil fuel is burned to generate more electrical energy. However, this expensive cost of burning fossil fuels can be saved by replacing them with renewable energy sources such as wind energy. Wind energy can be generated by using a wind turbine. Therefore, this study aims to develop a vertical axis wind turbine (VAWT) that can work effectively in highway wind speed conditions while evaluating its performance in terms of torque and power by using a simulation approach. The simulation involves the use of K-omega shear-stress transport (SST) as the turbulence viscosity model. The VAWT undergoes two types of tests during the simulation process. In Test 1, the wind turbine is tested with a various number of blades at constant wind speed to find which model has the best performance in terms of torque and power output. Then, the selected model with the better output proceeds to Test 2 where it is tested...

This study presents an overview on the possibilities of interior noise reduction for monorail sys... more This study presents an overview on the possibilities of interior noise reduction for monorail system using passive means. Nine samples out of three materials were subjected for noise test and the performance of each sample was observed. It is found that all of these samples have proved to reduce a significant amount noise at low and high frequencies even though the amount reduced differ from one sample to another. It is also been noticed that this reductions were denominated by means of absorption for some samples such as those from rubber material, and it was dominated by means of reflection for some others such as those from aluminum composite and paper composite. Moreover, from these different acoustic properties of each material, the whereabouts to install every material is different as well. It was suggested that, the rubber material should be installed on the upper floor of the monorail while, the paper composite should be installed under floor, and the aluminum composite shou...

Applied Mechanics and Materials, 2015

Numerical study using ANSYS Fluent is conducted to investigate the effects of louver angle on pre... more Numerical study using ANSYS Fluent is conducted to investigate the effects of louver angle on pressure drop and heat transfer of a heat exchanger. Flow simulations are conducted on 3D modeling of multi stacks louvered fins at three different parameters of louver angles which are 22.0o, 25.5o and 29.0o with Reynolds number ranging from 200 to 1000. These Reynolds numbers are based on louver pitch and fin pitch. The flow temperature is set at 300K which is the room temperature, while temperature of louver fin is set at 400K. The results show that Reynolds number based on fin pitch 2.02 mm and louver angle of 22.0o generate higher performance of heat exchanger compared to louver pitch of 1.40 mm and the other louver angles. Therefore, configuration of Reynolds number based on fin pitch 2.02 mm and louver angle 22.0o is preferred to be adopted in the design process of heat exchanger.

Applied Mechanics and Materials, 2013

This paper presents the effect of the changes in fin geometry on pressure drop and heat transfer ... more This paper presents the effect of the changes in fin geometry on pressure drop and heat transfer characteristics of louvered fin heat exchanger numerically. Three dimensional simulation using ANSYS Fluent have been conducted for six different configurations at Reynolds number ranging from 200 to 1000 based on louver pitch. The performance of this system has been evaluated by calculating pressure drop and heat transfer coefficient. The result shows that, the fin pitch and the louver pitch have a very considerable effect on pressure drop as well as heat transfer rate. It is observed that increasing the fin pitch will relatively result in an increase in heat transfer rate but at the same time, the pressure drop will decrease. On the other hand, low pressure drop and low heat transfer rate will be obtained when the louver pitch is increased. Final result shows a good agreement between experimental and numerical results of the louvered fin which is about 12%. This indicates the capabilit...

CFD Letters

The Savonius wind turbine is considered as one of the solutions for harvesting the kinetic energy... more The Savonius wind turbine is considered as one of the solutions for harvesting the kinetic energy from the wind in the urban areas, due to magnificent features such as, low construction cost, high starting torque, and self-starting ability especially at low wind speed. However, the conventional rotor suffers from low efficiency. Thus, modifying the configuration of the rotor may be an effective solution for providing electricity to the communities with no access to the power grid. Thus, this investigation aims to study numerically the effect of adding two inner blades on the performance of the Savonius wind rotor at low tip speed ratios (TSRs). The simulations are carried out using the two-dimensional simulation with the assist of ANSYS software. For turbulence modelling, the K-ε/realizable model was adopted in this study. Power coefficient (C p) and torque coefficient (C t) at various TSRs for the rotor are determined under a constant external overlap of 0.018 m. Furthermore, the effect of space between the inner blades was also investigated using three values of spacing. The simulation results show that the rotor with two inner blades performs better than the same rotor without inner blades at all tested TSRs expect at low considered values of 0.2 and 0.25. The heights Cp was 0.188 with 17.1% performance improvement at TSR = 0.4. Furthermore, the numerical results show that C p values decrease with the decrease of the space between the blades.

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences

The use of solar thermal technologies has shown great prospects towards solar energy conversion i... more The use of solar thermal technologies has shown great prospects towards solar energy conversion into more useful forms of energy and has increasingly expanded solar thermal technology applications. However, the inability to properly store the excess solar energies during peak hours and demands have limited many of their applications. The integration of thermal energy storage (TES) systems with thermal technologies have increased the solar thermal technology performance but the poor thermal characteristics exhibited by phase change materials (PCM) limited the system overall performance. The enhancement of PCM properties by nonadditive have shown increased material performance in TES application and thereby extending the use of solar thermal technology application. Given this narrative and identifies literature gaps, the present study investigated experimentally the enhancement of paraffin PCM using nonadditive metallic of different types and concentrations and analysed their thermal ...

International Journal of Integrated Engineering

Fluids

The present paper aims to study the possibility of dispensing an auxiliary power unit (APU) in an... more The present paper aims to study the possibility of dispensing an auxiliary power unit (APU) in an aircraft powered by fossil fuels to reduce air pollution. It particularly seeks to evaluate the amount of power generated by the ram air turbine (RAT) using the novel counter-rotating technique while characterizing its optimum axial distance. The ram air turbine (RAT), which is already equipped in aircrafts, was enhanced to generate the amount of energy produced by the APU. The approach was implemented by a CRRAT system. Six airfoil profiles were tested based on 2D models and the best airfoil was chosen for implantation on the RAT and CRRAT systems. The performance of the conventional single-rotor RAT and CRRAT were analyzed using FLUENT software based on 3D models. The adopted numerical scheme was the Navier–Stokes equation with k–ω SST turbulence modeling. The dynamic mesh and user-defined function (UDF) were used to revolve the rotor turbine via wind. The results indicated that the F...

The International Journal of Integrated Engineering

Wind power is sustainable and prevalent virtually all over the globe. However, the conversion eff... more Wind power is sustainable and prevalent virtually all over the globe. However, the conversion efficiency of the conventional single-rotor wind turbine (SRWT) is still far from satisfactory. The dual-rotor counter-rotating concept is among the reliable techniques used to enhance the efficiency of a wind energy conversion device for its renowned effectiveness. This study aims to investigate the performance of a Savonius dual/twin-rotor system, particularly in low-speed wind conditions while employing the counter-rotating technique. The evaluation of this technique is presented in terms of aerodynamic characteristics, including the power and torque coefficients. The results have shown that the new concept was able to improve the performance of the system extensively and was capable of operating in a lower wind speed condition. Compared to a single-rotor system, an additional 42% more torque was possible owing to the existence of a second rotor in the new system. The results have also r...