Mohd Fadhli Zulkafli

Methods of Transport Technologies: A Review On Using Tube/Tunnel Systems

This review covers different ways of transporting goods through tubes and tunnel systems and summarizes their technologies from a mechanical engineering point of view as well as provides a synopsis of the works over the past three decades which were carried out all over the world. The review explored their implementation possibilities in order to meet the high demand of fast and reliable transportation system, especially in big cities. Such of the new system may provide and offer many environmental and safety benefits, such as reducing traffic jams, accidents, air pollution. It had been found that many research and developments concerning the transport technologies have been accomplished. Basically, there are two transportation systems that can be adapted for transporting goods, people, and variously freights through a tube or tunnel, namely pneumatics air tube base, and magnetic levitation approach. The progress of these approaches is discussed in this paper.

Flow Simulation of Modified Duct System Wind Turbines Installed on Vehicle

This study investigates the characteristics of airflow with a flow guide installed and output power generated by wind turbine system being installed on a pickup truck. The wind turbine models were modelled by using SolidWorks 2015 software. In order to investigate the characteristic of air flow inside the wind turbine system, a computer simulation (by using ANSYS Fluent software) is used. There were few models being designed and simulated, one without the rotor installed and another two with rotor installed in the wind turbine system. Three velocities being used for the simulation which are 16.7 m/s (60 km/h), 25 m/s (90 km/h) and 33.33 m/s (120 km/h). The study proved that the flow guide did give an impact to the output power produced by the wind turbine system. The predicted result from this study is the velocity of the air inside the ducting system of the present model is better that reference model. Besides, the flow guide implemented in the ducting system gives a big impact on the characteristics of the air flow.

Small Horizontal Axis Wind Turbine under High Speed Operation: Study of Power Evaluation

Mechanical energy is produced through the rotation of wind turbine blades by air that convert the mechanical energy into electrical energy. Wind turbines are usually designed to be use for particular applications and design characteristics may vary depending on the area of use. The variety of applications is reflected on the size of turbines and their infrastructures, however, performance enhancement of wind turbine may start by analyzing the small horizontal axis wind turbine (SHAWT) under high wind speed operation. This paper analyzes the implementations of SHAWT turbines and investigates their performance in both simulation and real life. Depending on the real structure of the rotor geometry and aerodynamic test, the power performance of the SHAWT was simulated using ANSYS-FLUENT software at different wind speed up to 33.33 m/s (120km/h) in order to numerically investigate the actual turbine operation. Dynamic mesh and user define function (UDF) was used for revolving the rotor turbine via wind. Simulation results were further validated by experimental data and hence good matching was yielded. And for reducing the energy producing cost, car alternator was formed to be used as a small horizontal wind turbine. As a result, alternator-based turbine system was found to be a low-cost solution for exploitation of wind energy.

Evaluation of Wind Energy Potential as a Power Generation Source in Chad

Long-term wind speed data for thirteen meteorological stations, measured over a five-year period, were statistically analyzed using the two-parameter Weibull distribution function. The purpose of this study is to reveal for the first time the wind power potentials in Chad and to provide a comprehensive wind map of the country. The results show that the values of the shape and scale parameters varied over a wide range. Analysis of the seasonal variations showed that higher wind speed values occur when the weather condition is generally dry and they drop considerably when the weather condition is wet. It was also observed that the wind speed increases as one moves from the southern zone to the Saharan zone. Although the wind power at each site varies significantly, however, the potentials of most of the sites were encouraging. Nevertheless, according to the PNNL classification system, they are favorable for small-scale applications only. A few stations in the middle of Sudanian and Sahel regions are found to be not feasible for wind energy generation due to their poor mean wind speed. The prevailing wind direction for both Saharan and Sahel regions is dominated by northeastern wind, while it diverged to different directions in the Sudanian zone.

Experimental and numerical simulation of a moving carrier (FX63-137) through an air tunnel

This study investigated the movement of a carrier through an air tunnel using numerical simulation and experimental approach conducted in UTHM laboratories. The carrier was designed to have a particular trajectory moves along the air tunnel. The body of the main carrier has a shape of cube and rectangular wing of aspect ratio 2 is set in the middle of the body which has a shape of airfoil FX63-137 as its airfoil section. Experimental result of the carrier movement was investigated and compared with the simulation result obtained by Fluents software. The experiment was conducted using a flow speed of 19.59 m/s at the inlet station. In the simulation, the flow is considered as an internal flow and has a constant temperature at the entry station. The pressure ratio between the inlet and outlet of the air tunnel is 235 N/m2. In addition, that the flow is considered as turbulent flow and the present study used k – e as its turbulence modelling in the numerical simulation. Comparison result between experiment and Fluent software in term of its trajectory and the speed of the carrier movement are found in a good agreement.

Numerical analysis on centrifugal compressor with membrane type dryer

Moisture content is a common phenomenon in industrial processes especially in oil and gas industries. This contaminant has a lot of disadvantages which can lead to mechanical failure DEC (Deposition, Erosion & Corrosion) problems. To overcome DEC problem, this study proposed to design a centrifugal compressor with a membrane type dryer to reduce moisture content of a gas. The effectiveness of such design has been analyzed in this study using Computational Fluid Dynamics (CFD) approach. Numerical scheme based on multiphase flow technique is used in ANSYS Fluent software to evaluate the moisture content of the gas. Through this technique, two kind of centrifugal compressor, with and without membrane type dryer has been tested. The results show that the effects of pressure on dew point temperature of the gas change the composition of its moisture content, where high value lead more condensation to occur. However, with the injection of cool dry gas through membrane type dryer in the centrifugal compressor, the pressure and temperature of moisture content as well as mass fraction of H2O in centrifugal compressor show significant reduction.

A comparative study on the motion of various objects inside an air tunnel

This paper presents a comparative study of the movement of various rigid bodies through an air tunnel for both two and three-dimensional flow problems. Three kinds of objects under investigation are in the form of box, ball and wedge shape. The investigation was carried out through the use of a commercial CFD software, named Fluent, in order to determine aerodynamic forces, act on the object as well as to track its movement. Adopted numerical scheme is the time-averaged Navier-Stokes equation with k - e as its turbulence modeling and the scheme was solved using the SIMPLE algorithm. Triangular elements grid was used in 2D case, while tetrahedron elements for 3D case. Grid independence studies were performed for each problem from a coarse to fine grid. The motion of an object is restricted in one direction only and is found by tracking its center of mass at every time step. The result indicates the movement of the object is increasing as the flow moves down stream and the box have the fastest speed compare...

A survey on the use of ram air turbine in aircraft

Ram Air Turbine (RAT) is used as an emergency power source to feed vital apparatuses required for aircrafts in case of main systems failure. The purpose of this paper is to explain the function of RAT as a wind harvesting technology for aircraft and its advantages as auxiliary power generator during landing process. This survey allows a more axiomatic understanding on the use of different RAT approaches in aircraft construction. The survey in this paper also provides a sight to simultaneously use RAT for emergency case and power harvesting as future energy.

Assessment of wind energy potential in the capital city of Chad, N’Djamena

In this study, statistical analysis of a long term meteorological data of 10 years have been presented to reveal the potential of wind power as a source of energy generation in the capital of Chad, N’Djamena. The recent ten-year period wind data were collected from the Hassan Djamous International Airport at N’Djamena. The wind characteristics and wind energy potential were analyzed using Weibull distribution function. The results show that the values of the shape parameter k, and scale parameter c, varied over a wide range. The annual highest values of the Weibull shape parameter k, and scale parameter c, were 1.59 and 4.12 m/s respectively. It was also found that higher wind speeds occurred during dry season, i.e. November to July and the lower wind speeds occurred during the wet season, i.e. August to October. The annual average of the most probable wind speed and wind speed carrying maximum energy were respectively 1.86 m/s and 6.48 m/s. Likewise, the wind power density was ranging between 55.96 W/m2 ...

Numerical analysis for comparison of aerodynamic characteristics of six airfoils

Comparison of six airfoils; FX 63-137, FX76-100, S835, S809, NACA63415, and NACA63215, have been performed using commercial software, FLUENT and XFOIL, in order to choose the best maximum lift to drag ratio in the region of 4×10∧6 Reynolds number, and also to specify their aerodynamic coefficients in Blade Element Momentum theory (BEM). These airfoils are candidates for the use as blade turbines and another application of flying object operating at high Reynolds number. In this study, the two-dimensional model of airfoils was established through Gambit software. The range of angles of attack is from -150 to 150. Comparisons of the numerical results generally show good agreements. Numerical results of FX 63-137 were also validated with experimental data. A good agreement of lift and drag coefficient from numerical simulations of FLUENT and experimental data was obtained at 10∧6 Reynolds number.