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N.A. Razak
Universiti Sains Malaysia

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Review
Published: 07 August 2020
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Carbon dioxide, CO2 accounts for most of the emission from all the types of greenhouse gasses in the world. The ability of CO2 to remain longer than other greenhouse gases and the convenience of producing CO2 has resulted in its high projection in a yearly manner. The prime factor for the emission of CO2 are from the actions of human beings. One such human act is the concrete industry. Total emissions from the concrete industry could therefore contribute as much as 8% of global CO2 emissions. Sequestered CO2 in concrete can provide an impact on reducing the carbon footprint and is also able to improve the compressive strength of concrete. During this process, the sequestered carbon dioxide chemically reacts with cement to produce a mineral, trapping carbon dioxide gas in the concrete. Hence, sequestering carbon dioxide gas in concrete does not only on a bigger scale reduces carbon footprint, but it also reduces the impact the construction industry has on the environment. This paper presents a detailed review on the chemical reaction that takes place during the sequestration of carbon dioxide and the research published on the effects of carbon dioxide sequestered concrete on its properties. The impact this process has on the concrete industry and the environment is discussed in this paper.

ACS Style

Nur Liyana Mohd Kamal; Zarina Itam; Yuovendra Sivaganese; Norizham Abdul Razak. Carbon Dioxide Sequestered Concrete: A Review Paper. 2020, 1 .

AMA Style

Nur Liyana Mohd Kamal, Zarina Itam, Yuovendra Sivaganese, Norizham Abdul Razak. Carbon Dioxide Sequestered Concrete: A Review Paper. . 2020; ():1.

Chicago/Turabian Style

Nur Liyana Mohd Kamal; Zarina Itam; Yuovendra Sivaganese; Norizham Abdul Razak. 2020. "Carbon Dioxide Sequestered Concrete: A Review Paper." , no. : 1.

Conference paper
Published: 13 June 2020 in Recent Advances in Computational Mechanics and Simulations
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Application of biomimetic systems has been an advancement in the robotic field. The development of underwater robot imitates the locomotion and flow around a swimming fish since its manoeuvrability and efficiency is excellent. The work presented in this manuscript aimed to visualize the flow of a real fishtail to aid the design and fabrication of a mechanical fishtail. The flow across the tail of a Gourami fish when it was visualized and observed in a water channel under static water condition. The tail kinematics of the real fish were extracted and applied on the designed mechanical fishtail. The designed mechanical fishtail was employed to undergo the flow visualization experiment using Particle Image Velocimetry (PIV). The experiment was conducted with the flow in the water channel set at a velocity of 0.2 m/s while the mechanical fishtail was set to flap with an amplitude of 20°. Measurements were repeated with the tail flapping amplitude of 40°. Chain of vortices was observed to be generated by both real fishtail and mechanical fishtail. Through comparison, it is noticed that the flow pattern generated by the mechanical fishtail flapping with the amplitude of 20° has the highest similarity with the actual Gourami fish compare to the flapping amplitude of 40°.

ACS Style

Lai Hoong Chuin; Soh Ling Xin; N. A. Razak; Zarina Itam; A. F. Osrin. Flow Field Measurement of Wake Generated by Gourami Fish Tail. Recent Advances in Computational Mechanics and Simulations 2020, 207 -217.

AMA Style

Lai Hoong Chuin, Soh Ling Xin, N. A. Razak, Zarina Itam, A. F. Osrin. Flow Field Measurement of Wake Generated by Gourami Fish Tail. Recent Advances in Computational Mechanics and Simulations. 2020; ():207-217.

Chicago/Turabian Style

Lai Hoong Chuin; Soh Ling Xin; N. A. Razak; Zarina Itam; A. F. Osrin. 2020. "Flow Field Measurement of Wake Generated by Gourami Fish Tail." Recent Advances in Computational Mechanics and Simulations , no. : 207-217.

Conference paper
Published: 13 June 2020 in Recent Advances in Computational Mechanics and Simulations
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Flying fish is a fascinating animal that has the abilities to swim and glide. These unique abilities have attracted interest amongst scientist and researchers alike. Several studies have been performed to better understand flying fish aerial locomotion and aerodynamics performance. However, understanding biological beings’ aerodynamics characteristics such as flying fish have always been more than educated estimation. Researchers have approximated the physics of flying fish based on known aerodynamics principle of other flying animals with similarly aerodynamics parameters. In the present study, we manufactured and tested a model of Exocoetus Volitans flying fish in the wind tunnel. The experiment evaluated the lift and drag coefficients generated by Exocoetus Volitans wings by subtracting the aerodynamics forces contribution from other fish parts. The experiment evaluated the performance at various angles of attacks starting from −15° to +45° and airspeeds ranging from 10 to 15 m/s. The results show that as the angle of attack increases, the lift and drag coefficients also increase even beyond 20°. The maximum lift coefficient is achieved when the angle of attack is at 40°.

ACS Style

A. F. Osrin; N. A. Razak; Aizat Abbas; Zarina Itam. Lift and Drag Trend of Exocoetus Volitans Model in the Wind Tunnel. Recent Advances in Computational Mechanics and Simulations 2020, 271 -278.

AMA Style

A. F. Osrin, N. A. Razak, Aizat Abbas, Zarina Itam. Lift and Drag Trend of Exocoetus Volitans Model in the Wind Tunnel. Recent Advances in Computational Mechanics and Simulations. 2020; ():271-278.

Chicago/Turabian Style

A. F. Osrin; N. A. Razak; Aizat Abbas; Zarina Itam. 2020. "Lift and Drag Trend of Exocoetus Volitans Model in the Wind Tunnel." Recent Advances in Computational Mechanics and Simulations , no. : 271-278.

Journal article
Published: 01 May 2020 in Journal of Applied Fluid Mechanics
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ACS Style

H. Abu Bakar; A. Abas; Norizham Abdul Razak. Stent Porosity Efficiency in Treating Wide-Neck Saccular Renal Artery Aneurysm. Journal of Applied Fluid Mechanics 2020, 13, 893 -908.

AMA Style

H. Abu Bakar, A. Abas, Norizham Abdul Razak. Stent Porosity Efficiency in Treating Wide-Neck Saccular Renal Artery Aneurysm. Journal of Applied Fluid Mechanics. 2020; 13 (3):893-908.

Chicago/Turabian Style

H. Abu Bakar; A. Abas; Norizham Abdul Razak. 2020. "Stent Porosity Efficiency in Treating Wide-Neck Saccular Renal Artery Aneurysm." Journal of Applied Fluid Mechanics 13, no. 3: 893-908.

Journal article
Published: 01 December 2019 in International Journal of Cardiology
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ACS Style

G. Abu Bakar; A. Abas; N.H. Mokhtar; Norizham Abdul Razak; J.W. Chai; M.N. Abdul Hamid. The Study of Blood Hemodynamic and Thrombosis Formation in Bi-leaflet Mechanical Heart Valve of Different Configurations. International Journal of Cardiology 2019, 297, 26 .

AMA Style

G. Abu Bakar, A. Abas, N.H. Mokhtar, Norizham Abdul Razak, J.W. Chai, M.N. Abdul Hamid. The Study of Blood Hemodynamic and Thrombosis Formation in Bi-leaflet Mechanical Heart Valve of Different Configurations. International Journal of Cardiology. 2019; 297 ():26.

Chicago/Turabian Style

G. Abu Bakar; A. Abas; N.H. Mokhtar; Norizham Abdul Razak; J.W. Chai; M.N. Abdul Hamid. 2019. "The Study of Blood Hemodynamic and Thrombosis Formation in Bi-leaflet Mechanical Heart Valve of Different Configurations." International Journal of Cardiology 297, no. : 26.

Articles
Published: 27 November 2019 in Biofuels
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Spray characteristics and transient behaviour of alternative fuel droplets at different spray cone angles, injection pressures and droplet diameters are presented, using a simple spray evaporation model. The model only considers drag force acting on the droplet. Radiation heat transfer during the evaporation process is neglected. The model incorporates temperature-dependent fuel properties, drag coefficient and Reynolds number for robustness. It is tested for alternative fuels, namely Jatropha Bio-synthetic Paraffinic Kerosen (JSPK), Camelina Bio-synthetic Paraffinic Kerosene (CSPK) and biodiesel, while Jet-A is used for comparison. The transient behaviour of fuel droplets is visualised through a time-history of the normalised squared diameter. Changes in the particles’ temperature, mass, density, velocity and heat transfer coefficient over time are observed. Moreover, penetration of the fuels at different spray cone angles, injection pressures and droplet diameters is compared. Among the tested fuels, biodiesel is found to have the farthest penetration due to its high vapour pressure. Notably, increasing spray cone angle reduces penetration length. A similar trend is observed when injection pressure is increased. However, at constant injection pressure, increasing droplet diameter increases spray cone angle and spray penetration. To obtain optimum penetration, therefore, a larger cone angle should be used for fuel with high density and vapour pressure, and vice versa.

ACS Style

Joanne Lim; Norizham Abdul Razak; Nurul Musfirah Mazlan. An evaluation of alternative fuels’ spray penetration at various spray cone angles and injection pressures using a simple evaporation model. Biofuels 2019, 1 -11.

AMA Style

Joanne Lim, Norizham Abdul Razak, Nurul Musfirah Mazlan. An evaluation of alternative fuels’ spray penetration at various spray cone angles and injection pressures using a simple evaporation model. Biofuels. 2019; ():1-11.

Chicago/Turabian Style

Joanne Lim; Norizham Abdul Razak; Nurul Musfirah Mazlan. 2019. "An evaluation of alternative fuels’ spray penetration at various spray cone angles and injection pressures using a simple evaporation model." Biofuels , no. : 1-11.

Journal article
Published: 01 July 2019 in Journal of Applied Fluid Mechanics
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ACS Style

H. Abu Bakar; A. Abas; Norizham Abdul Razak. Effectiveness of Stent in the Treatment of Renal Artery Aneurysm using FSI Simulation. Journal of Applied Fluid Mechanics 2019, 12, 1347 -1358.

AMA Style

H. Abu Bakar, A. Abas, Norizham Abdul Razak. Effectiveness of Stent in the Treatment of Renal Artery Aneurysm using FSI Simulation. Journal of Applied Fluid Mechanics. 2019; 12 (4):1347-1358.

Chicago/Turabian Style

H. Abu Bakar; A. Abas; Norizham Abdul Razak. 2019. "Effectiveness of Stent in the Treatment of Renal Artery Aneurysm using FSI Simulation." Journal of Applied Fluid Mechanics 12, no. 4: 1347-1358.

Conference paper
Published: 01 January 2019 in Materials Today: Proceedings
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ACS Style

Z. Itam; S. Beddu; D. Mohammad; N.L.M. Kamal; Norizham Abdul Razak; Z.A.A. Hamid. Simulation of Alkali-Silica Reaction Model in a Concrete Gravity Dam at the Macroscale and Mesoscale. Materials Today: Proceedings 2019, 17, 717 -726.

AMA Style

Z. Itam, S. Beddu, D. Mohammad, N.L.M. Kamal, Norizham Abdul Razak, Z.A.A. Hamid. Simulation of Alkali-Silica Reaction Model in a Concrete Gravity Dam at the Macroscale and Mesoscale. Materials Today: Proceedings. 2019; 17 ():717-726.

Chicago/Turabian Style

Z. Itam; S. Beddu; D. Mohammad; N.L.M. Kamal; Norizham Abdul Razak; Z.A.A. Hamid. 2019. "Simulation of Alkali-Silica Reaction Model in a Concrete Gravity Dam at the Macroscale and Mesoscale." Materials Today: Proceedings 17, no. : 717-726.

Conference paper
Published: 01 January 2019 in Materials Today: Proceedings
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ACS Style

Z. Itam; S. Beddu; D. Mohammad; N.L.M. Kamal; M.M. Zainoodin; A. Syamsir; Norizham Abdul Razak; Z.A.A. Hamid. Extraction of Metal Oxides from Coal Bottom Ash by Carbon Reduction and Chemical Leaching. Materials Today: Proceedings 2019, 17, 727 -735.

AMA Style

Z. Itam, S. Beddu, D. Mohammad, N.L.M. Kamal, M.M. Zainoodin, A. Syamsir, Norizham Abdul Razak, Z.A.A. Hamid. Extraction of Metal Oxides from Coal Bottom Ash by Carbon Reduction and Chemical Leaching. Materials Today: Proceedings. 2019; 17 ():727-735.

Chicago/Turabian Style

Z. Itam; S. Beddu; D. Mohammad; N.L.M. Kamal; M.M. Zainoodin; A. Syamsir; Norizham Abdul Razak; Z.A.A. Hamid. 2019. "Extraction of Metal Oxides from Coal Bottom Ash by Carbon Reduction and Chemical Leaching." Materials Today: Proceedings 17, no. : 727-735.

Conference paper
Published: 12 November 2018 in AIP Conference Proceedings
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Most of the world’s energy production is still mainly achieved by the combustion of coal in power stations. In Malaysia, seven power plants under Tenaga Nasional Berhad Malaysia (TNB) continuously produce around 790 tons of Coal Bottom Ash (CBA) per day. These vast volumes pose a problem in the disposal of the CBA which conventionally is loaded onto ash landfills. Many of the metals and oxides contained by the CBA are environmentally hazardous. When the CBA is disposed in landfills, the metal oxides are leached out and find their way into potable water and into animal and plantations. Disposal of the unused CBA is costly and poses financial disadvantages to power station and to the environment. However, the metals contained inside the CBA may be valuable to various industry if there is a way to extract the metals out of the CBA. This study focused on investigating the extraction of iron from coal bottom ash by the carbon reduction method. The rationale for this process was that by removing and recovering these major constituent elements from the ash, it would be easier to concentrate and isolate the trace elements especially the rare earth elements that are present in the CBA. The chemical composition of the CBA is then determined by x-ray fluorescence. The main mineral phases in CBA were determined to be quartz, aluminium oxide and iron (III) oxide. The experimental results obtained from the carbon reduction method showed that the optimum time for the reduction of iron (III) oxide by carbon from CBA is 30 minutes and the optimum temperature for the reduction is 800°C.

ACS Style

Z. Itam; N. L. M. Kamal; A. Syamsir; S. Beddu; D. Muhammad; N. M. Zahari; L. M. Kai; Z. A. A. Hamid; Norizham Abdul Razak. Extraction of iron from coal bottom ash by carbon reduction method. AIP Conference Proceedings 2018, 2030, 020261 .

AMA Style

Z. Itam, N. L. M. Kamal, A. Syamsir, S. Beddu, D. Muhammad, N. M. Zahari, L. M. Kai, Z. A. A. Hamid, Norizham Abdul Razak. Extraction of iron from coal bottom ash by carbon reduction method. AIP Conference Proceedings. 2018; 2030 (1):020261.

Chicago/Turabian Style

Z. Itam; N. L. M. Kamal; A. Syamsir; S. Beddu; D. Muhammad; N. M. Zahari; L. M. Kai; Z. A. A. Hamid; Norizham Abdul Razak. 2018. "Extraction of iron from coal bottom ash by carbon reduction method." AIP Conference Proceedings 2030, no. 1: 020261.

Conference paper
Published: 17 October 2018 in MATEC Web of Conferences
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Aeration is an important parameter in water filtration system as it allows the transfer of oxygen to water through turbulence effect which subsequently increases air entrainment in the water. For water treatment application, aeration efficiency is measured to ensure continuous re-oxygenation of the unfiltered water. Aside from aeration, this paper also studies the flow patterns through the use of particle image velocimetry (PIV) setup. Through the use of real scale down physical model laboratory study is performed using PIV to obtain the velocity profile. These velocity profiles will then be used to calculate the aeration efficiency of the water in a cascade aerator system. Based on the findings, the aeration efficiency obtained from the PIV experiment has a maximum value at the lowest point of the cascade aerator system with a value of 0.0139 due to increase in mass flow rate as it moves through the steps with velocity of 0.418 m/s. Therefore, in the design of a cascade aerator system, it is advisable to increase the number of steps since it will increase the aeration efficiency of the system.

ACS Style

A. Azman; M. H. Zawawi; N. H. Hassan; A. Abas; Norizham Abdul Razak; A. Z. A. Mazlan; M.A.Z Mohd Remy Rozainy. Effect of Step Height On the Aeration Efficiency of Cascade Aerator System Using Particle Image Velocimetry. MATEC Web of Conferences 2018, 217, 04005 .

AMA Style

A. Azman, M. H. Zawawi, N. H. Hassan, A. Abas, Norizham Abdul Razak, A. Z. A. Mazlan, M.A.Z Mohd Remy Rozainy. Effect of Step Height On the Aeration Efficiency of Cascade Aerator System Using Particle Image Velocimetry. MATEC Web of Conferences. 2018; 217 ():04005.

Chicago/Turabian Style

A. Azman; M. H. Zawawi; N. H. Hassan; A. Abas; Norizham Abdul Razak; A. Z. A. Mazlan; M.A.Z Mohd Remy Rozainy. 2018. "Effect of Step Height On the Aeration Efficiency of Cascade Aerator System Using Particle Image Velocimetry." MATEC Web of Conferences 217, no. : 04005.

Conference paper
Published: 19 September 2018 in MATEC Web of Conferences
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Wind tunnel testing of single-storey isolated building with 1: 100 scale down model was carried out in an open circuit wind tunnel without roughness elements facilities. The gable roof building model with 30˚ roof pitch was studied for wind directions of 0˚, 30˚, 45˚, 60˚ and 90˚. Pressure measurements were performed on all the walls and the roof (Zone 1, 2, 3, 4 and 5) of the building model with wind speed of 12 m/s. The results showed that the high suctions were generally induced by the 90˚ wind direction for Zone 1 and 60˚ and 90˚ wind directions for Zone 2. Mostly, high suction was also observed in case of 45˚ and 60˚ wind direction in Zone 3. In zone 4 and zone 5, high suction was generally induced by the 0˚ wind direction.

ACS Style

S S Zaini; N Rossli; Taksiah A. Majid; Siti Noratikah Che Deraman; N A Razak. Wind Directional Effect on a Single Storey House Using Educational Wind Tunnel. MATEC Web of Conferences 2018, 206, 01006 .

AMA Style

S S Zaini, N Rossli, Taksiah A. Majid, Siti Noratikah Che Deraman, N A Razak. Wind Directional Effect on a Single Storey House Using Educational Wind Tunnel. MATEC Web of Conferences. 2018; 206 ():01006.

Chicago/Turabian Style

S S Zaini; N Rossli; Taksiah A. Majid; Siti Noratikah Che Deraman; N A Razak. 2018. "Wind Directional Effect on a Single Storey House Using Educational Wind Tunnel." MATEC Web of Conferences 206, no. : 01006.

Journal article
Published: 01 September 2018 in Journal of Applied Fluid Mechanics
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ACS Style

H. Abu Bakar; A. Abas; N. Hafizah Mokhtar; Norizham Abdul Razak; M. Najib Bin Abdul Hamid. Particle Image Velocimetry and Finite Volume Method Study of Bi-leaflet Artificial Heart Valve. Journal of Applied Fluid Mechanics 2018, 11, 1365 -1375.

AMA Style

H. Abu Bakar, A. Abas, N. Hafizah Mokhtar, Norizham Abdul Razak, M. Najib Bin Abdul Hamid. Particle Image Velocimetry and Finite Volume Method Study of Bi-leaflet Artificial Heart Valve. Journal of Applied Fluid Mechanics. 2018; 11 (5):1365-1375.

Chicago/Turabian Style

H. Abu Bakar; A. Abas; N. Hafizah Mokhtar; Norizham Abdul Razak; M. Najib Bin Abdul Hamid. 2018. "Particle Image Velocimetry and Finite Volume Method Study of Bi-leaflet Artificial Heart Valve." Journal of Applied Fluid Mechanics 11, no. 5: 1365-1375.

Journal article
Published: 01 May 2018 in Instruments and Experimental Techniques
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We report on the implementation of the low cost multiple high power light-emitting diodes (HPLEDs) as illumination source for particle image velocimetry measurements in a water tank. The illumination system consists of a custom-built circuit developed using off-the-shelf components for driving the HPLEDs beyond its recommended rating. Two 20 W green LEDs were employed as the pulse illumination light source. The incoherent light generated by the LEDs is channeled into a fiber optic bundle linked to a cylindrical lens for light sheet generation. The light produced by the LEDs was first characterized in term of its wavelength and illuminance properties with respect to input power and pulsing frequency. The complete system was then evaluated by studying the flow around NACA 0018 airfoil in the water tank filled with the seeding particles. The developed system was able to capture the flow field generated by the airfoil when moving at various attack angles. Images acquired using both laser-based and HPLEDs based illumination systems are compared. The results obtained demonstrate the feasibility of the developed low cost HPLED illumination system.

ACS Style

L. H. Chuin; A. F. Omar; M. Z. Abdullah; N. A. Razak. Characterization and Evaluation of PIV Illumination System Using High Power Light Emitting Diodes for WaterTank Applications. Instruments and Experimental Techniques 2018, 61, 436 -444.

AMA Style

L. H. Chuin, A. F. Omar, M. Z. Abdullah, N. A. Razak. Characterization and Evaluation of PIV Illumination System Using High Power Light Emitting Diodes for WaterTank Applications. Instruments and Experimental Techniques. 2018; 61 (3):436-444.

Chicago/Turabian Style

L. H. Chuin; A. F. Omar; M. Z. Abdullah; N. A. Razak. 2018. "Characterization and Evaluation of PIV Illumination System Using High Power Light Emitting Diodes for WaterTank Applications." Instruments and Experimental Techniques 61, no. 3: 436-444.

Conference paper
Published: 01 May 2018 in IOP Conference Series: Materials Science and Engineering
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In past decades, particle image velocimetry (PIV) has been widely used in measuring fluid flow and a lot of researches have been done to improve the PIV technique. Many researches are conducted on high power light emitting diode (HPLED) to replace the traditional laser illumination system in PIV. As an extended work to the research in PIV illumination system, two high power light emitting diodes (HPLED) with different wavelength are introduced as PIV illumination system. The objective of this research is using dual colours LED to directly replace laser as illumination system in order for a single frame to be captured by a normal camera instead of a high speed camera. Dual colours HPLEDs PIV are capable with single frame double pulses mode which able to plot the velocity vector of the particles after correlation. An illumination system is designed and fabricated and evaluated by measuring water flow in a small tank. The results indicates that HPLEDs promises a few advantages in terms of cost, safety and performance. It has a high potential to be develop into an alternative for PIV in the near future.

ACS Style

Hc Lai; Tf Chew; Na Razak. Evaluation of Particle Image Velocimetry Measurement Using Multi-wavelength Illumination. IOP Conference Series: Materials Science and Engineering 2018, 370, 012044 .

AMA Style

Hc Lai, Tf Chew, Na Razak. Evaluation of Particle Image Velocimetry Measurement Using Multi-wavelength Illumination. IOP Conference Series: Materials Science and Engineering. 2018; 370 (1):012044.

Chicago/Turabian Style

Hc Lai; Tf Chew; Na Razak. 2018. "Evaluation of Particle Image Velocimetry Measurement Using Multi-wavelength Illumination." IOP Conference Series: Materials Science and Engineering 370, no. 1: 012044.

Conference paper
Published: 01 January 2018
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ACS Style

N. M. Kamal; Z. Itam; A. Syamsir; S. Beddu; D. Muhammad; A. F. A. Latif; Z. A. A. Hamid; Norizham Abdul Razak. Extraction of ferum from coal bottom ash using acid soluble and ion exchange leaching method. 2018, 1 .

AMA Style

N. M. Kamal, Z. Itam, A. Syamsir, S. Beddu, D. Muhammad, A. F. A. Latif, Z. A. A. Hamid, Norizham Abdul Razak. Extraction of ferum from coal bottom ash using acid soluble and ion exchange leaching method. . 2018; ():1.

Chicago/Turabian Style

N. M. Kamal; Z. Itam; A. Syamsir; S. Beddu; D. Muhammad; A. F. A. Latif; Z. A. A. Hamid; Norizham Abdul Razak. 2018. "Extraction of ferum from coal bottom ash using acid soluble and ion exchange leaching method." , no. : 1.

Journal article
Published: 01 November 2017 in Journal of Theoretical Biology
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Proper design of stent for application at specific aneurysm effect arteries could help to reduce the issues with thrombosis and aneurysm. In this paper, four types of stent configuration namely half-Y (6 mm), half-Y (4 mm), cross-bar, and full-Y configuration will implanted on real 3D artery bifurcation aneurysm effected arteries. Comparisons were then conducted based on the flow patterns after stent placement using both LBM-based solver and PIV experimental findings. According to the data obtained from all 4 stent designs, the flow profiles and the computed velocity from both methods were in agreement with each other. Both methods found that half-Y (6 mm) stent configuration is by far the best configuration in reducing the blood velocity at the vicinity of the aneurysm sac. The analysis also show that the half-Y (6 mm) stent configuration recorded the highest percentage of velocity reduction and managed to substantially reduce the pressure at the bifurcation region. This high flow velocity reduction through the use of half-Y stent could consequently promote the formation of thrombus thereby reducing the risk of rupture in the aneurysm sac.

ACS Style

N. Hafizah Mokhtar; Aizat Abas; N.A. Razak; Muhammad Najib Abdul Hamid; Soon Lay Teong. Effect of different stent configurations using Lattice Boltzmann method and particles image velocimetry on artery bifurcation aneurysm problem. Journal of Theoretical Biology 2017, 433, 73 -84.

AMA Style

N. Hafizah Mokhtar, Aizat Abas, N.A. Razak, Muhammad Najib Abdul Hamid, Soon Lay Teong. Effect of different stent configurations using Lattice Boltzmann method and particles image velocimetry on artery bifurcation aneurysm problem. Journal of Theoretical Biology. 2017; 433 ():73-84.

Chicago/Turabian Style

N. Hafizah Mokhtar; Aizat Abas; N.A. Razak; Muhammad Najib Abdul Hamid; Soon Lay Teong. 2017. "Effect of different stent configurations using Lattice Boltzmann method and particles image velocimetry on artery bifurcation aneurysm problem." Journal of Theoretical Biology 433, no. : 73-84.

Conference paper
Published: 24 July 2017 in PROCEEDING OF THE 3RD INTERNATIONAL CONFERENCE OF GLOBAL NETWORK FOR INNOVATIVE TECHNOLOGY 2016 (3RD IGNITE-2016): Advanced Materials for Innovative Technologies
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Lately, due to the growing interest in Micro Aerial Vehicles (MAV), interest in flapping flight has been rekindled. The reason lies in the improved performance of flapping wing flight at low Reynolds number regime. Many studies involving flapping wing flight focused on the generation of unsteady aerodynamic forces such as lift and thrust. There is one aspect of flapping wing flight that received less attention. The aspect is aerodynamic power consumption. Since most mechanical flapping wing aircraft ever designed are battery powered, power consumption is fundamental in improving flight endurance. This paper reports the results of experiments carried out on mechanical wings under going active root flapping and pitching in the wind tunnel. The objective of the work is to investigate the effect of the pitch angle oscillations and wing profile on the power consumption of flapping wings via generation of unsteady aerodynamic forces. The experiments were repeated for different airspeeds, flapping and pitching kinematics, geometric angle of attack and wing sections with symmetric and cambered airfoils. A specially designed mechanical flapper modelled on large migrating birds was used. It will be shown that, under pitch leading conditions, less power is required to overcome the unsteady aerodnamics forces. The study finds less power requirement for downstroke compared to upstroke motion. Overall results demonstrate power consumption depends directly on the unsteady lift force.

ACS Style

N. A. Razak; G. Dimitriadis; A. F. Razaami. Aerodynamics power consumption for mechanical flapping wings undergoing flapping and pitching motion. PROCEEDING OF THE 3RD INTERNATIONAL CONFERENCE OF GLOBAL NETWORK FOR INNOVATIVE TECHNOLOGY 2016 (3RD IGNITE-2016): Advanced Materials for Innovative Technologies 2017, 1865, 080001 .

AMA Style

N. A. Razak, G. Dimitriadis, A. F. Razaami. Aerodynamics power consumption for mechanical flapping wings undergoing flapping and pitching motion. PROCEEDING OF THE 3RD INTERNATIONAL CONFERENCE OF GLOBAL NETWORK FOR INNOVATIVE TECHNOLOGY 2016 (3RD IGNITE-2016): Advanced Materials for Innovative Technologies. 2017; 1865 (1):080001.

Chicago/Turabian Style

N. A. Razak; G. Dimitriadis; A. F. Razaami. 2017. "Aerodynamics power consumption for mechanical flapping wings undergoing flapping and pitching motion." PROCEEDING OF THE 3RD INTERNATIONAL CONFERENCE OF GLOBAL NETWORK FOR INNOVATIVE TECHNOLOGY 2016 (3RD IGNITE-2016): Advanced Materials for Innovative Technologies 1865, no. 1: 080001.

Journal article
Published: 30 June 2017 in International Review of Aerospace Engineering (IREASE)
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This paper reports on the result of wind tunnel test of a mechanical flapping wing undergoing pure flapping with elbow joint. The objective of this work is to investigate the effect of reduced frequency on the unsteady pressure distribution around a flapping wing cross section. A specially designed mechanical wing flapper with elbow joint was developed and tested. The data measured were the kinematics, airspeeds and pressure distribution around the outer wing cross section at three different reduced frequencies. The results revealed three distinct flow phenomena of attach flow, laminar separation bubble and dynamic stall occurring at the reduced frequencies tested. These flow characteristics are dependent on the instantaneous effective angle of attack of the wing during flapping. Copyright © 2017 Praise Worthy Prize - All rights reserved.

ACS Style

Ahmad F. Razaami; M. K. H. M. Zorkipli; H. C. Lai; M. Z. Abdullah; Norizham Abdul Razak. Unsteady Pressure Distribution of a Flapping Wing Undergoing Root Flapping Motion with Elbow Joint at Different Reduced Frequencies. International Review of Aerospace Engineering (IREASE) 2017, 10, 105 .

AMA Style

Ahmad F. Razaami, M. K. H. M. Zorkipli, H. C. Lai, M. Z. Abdullah, Norizham Abdul Razak. Unsteady Pressure Distribution of a Flapping Wing Undergoing Root Flapping Motion with Elbow Joint at Different Reduced Frequencies. International Review of Aerospace Engineering (IREASE). 2017; 10 (3):105.

Chicago/Turabian Style

Ahmad F. Razaami; M. K. H. M. Zorkipli; H. C. Lai; M. Z. Abdullah; Norizham Abdul Razak. 2017. "Unsteady Pressure Distribution of a Flapping Wing Undergoing Root Flapping Motion with Elbow Joint at Different Reduced Frequencies." International Review of Aerospace Engineering (IREASE) 10, no. 3: 105.

Journal article
Published: 18 April 2017 in Aerospace
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Flapping flight is an increasingly popular area of research, with applications to micro-unmanned air vehicles and animal flight biomechanics. Fast, but accurate methods for predicting the aerodynamic loads acting on flapping wings are of interest for designing such aircraft and optimizing thrust production. In this work, the unsteady vortex lattice method is used in conjunction with three load estimation techniques in order to predict the aerodynamic lift and drag time histories produced by flapping rectangular wings. The load estimation approaches are the Katz, Joukowski and simplified Leishman–Beddoes techniques. The simulations’ predictions are compared to experimental measurements from wind tunnel tests of a flapping and pitching wing. Three types of kinematics are investigated, pitch-leading, pure flapping and pitch lagging. It is found that pitch-leading tests can be simulated quite accurately using either the Katz or Joukowski approaches as no measurable flow separation occurs. For the pure flapping tests, the Katz and Joukowski techniques are accurate as long as the static pitch angle is greater than zero. For zero or negative static pitch angles, these methods underestimate the amplitude of the drag. The Leishman–Beddoes approach yields better drag amplitudes, but can introduce a constant negative drag offset. Finally, for the pitch-lagging tests the Leishman–Beddoes technique is again more representative of the experimental results, as long as flow separation is not too extensive. Considering the complexity of the phenomena involved, in the vast majority of cases, the lift time history is predicted with reasonable accuracy. The drag (or thrust) time history is more challenging.

ACS Style

Thomas Lambert; Norizham Abdul Razak; Grigorios Dimitriadis. Vortex Lattice Simulations of Attached and Separated Flows around Flapping Wings. Aerospace 2017, 4, 22 .

AMA Style

Thomas Lambert, Norizham Abdul Razak, Grigorios Dimitriadis. Vortex Lattice Simulations of Attached and Separated Flows around Flapping Wings. Aerospace. 2017; 4 (2):22.

Chicago/Turabian Style

Thomas Lambert; Norizham Abdul Razak; Grigorios Dimitriadis. 2017. "Vortex Lattice Simulations of Attached and Separated Flows around Flapping Wings." Aerospace 4, no. 2: 22.