CFD analysis on the effect of vortex generator on sedan car using ANSYS software

Nowadays, the demand for a high-speed car increases in which vehicle stability and fuel economy are the primary concern. The vehicle's aerodynamics plays a crucial role as it influences the overall performance of the vehicles. In the exploration of car aerodynamics, it involves studying various forces that act on a car while moving on the road, i.e., drag force, lift force. The leading causes of aerodynamic drag for automotive vehicles are the flow separation at the vehicles' rear end. By reducing the drag force, it is possible to increase the fuel economy. The research is focused on the effect of a vortex generator (VG) on a sedan car aerodynamics. The objective is to simulate fluid flow analysis for a sedan car that uses VG and without VG, to assess the effect of a different configuration of VG and the impact of a varying number of VG mounted on a sedan car in terms of flow pattern development and coefficient of drag (Cd). This study is conducted using two identical sedan car models, i.e., with VG and without VG. The flow around the vehicle has been considered incompressible. It is obtained by solving the incompressible form of the Reynolds Navier-Stokes (RANS) equations combined with the k-ε turbulence model. The simulation is run for different configuration of VG that acquire different radius of fillet, i.e., VG-1 (5 mm), VG-2 (30 mm) and VG-3 (50 mm) and for different number of VG that is mounted on a sedan car, i.e., 0 VG, 1 VG, 3 VG, 5 VG, 7 VG, and 9 VG. The data and results taken from this simulation show that the smallest fillet radius of VG, i.e., VG-1 (5 mm), is the best VG to be used on a sedan car. The results also show that, as the number of VGs increases, the drag coefficient is decreased. Hence, the best number of VGs to be used on a sedan car are nine VGs

Finite element modelling of fixed-fixed end plate attached with vibration absorber

The present paper investigated the effect of the lightweight dynamic vibration absorber (LDVA) to reduce vibration of thin walled structure. The free and forced vibration response of a rectangular thin plate were performed using finite element method. Subsequently, the effects of attached single and dual LDVA were analysed in depth by using Ansys workbench 14.5. Results demonstrated that single LDVA attached at the centre of the plate succesfully attenuate vibration over the frequency range of 0- 600 Hz. By contrast, attached with dual LDVA only suppresses the resonance of the first second and fourth modes but not for third and fifth modes of thin walled structure. It was found that by simply increasing the weight of mass does not improve the vibration absorption over the entire frequency range. The study conclude that attached single LDVA are better than dual LDVA for vibration absorption of thin walled structure over the entire frequency range

CFD Simulation of Air-Piloted Downdraft Gasification Process: A Comparative Study Between Coal and Palm Kernel Shell as Feedstock

A fixed bed downdraft gasifier model based on computational fluid dynamic (CFD) framework was developed to investigate the influence of feedstock (palm kernel shell [PKS] and coal) on the quality of syngas produced via the gasification process. Euler–Euler approach was utilized in this study to describe the gas and solid phases. Realizable k-ε turbulence model was used to evaluate the constitutive properties of the dispersed phase and the gas phase behavior. This simulation model was validated by comparing the syngas composition of gasification simulation of coal with previous research, which yielded the overall accuracy result of 83.2%. This study also highlighted that PKS gasification produced 53.74% and 90.51% higher composition of H2 and CO respectively as compared to coal gasification. Whereas coal gasification produced 81.35%, 71.31% and 52.29% higher composition of CH4, H2O and CO2 respectively as compared to PKS gasification. Hence, PKS produced 66.2% higher combustible gas of H2 and CO than coal. PKS is thus considered as a potential renewable feedstock for gasification process as an alternative to the non-renewable coal. In addition, PKS gasification produced 52.29% lesser composition of CO2 as compared to coal gasification

CFD Analysis on the Effect of Vortex Generator on Sedan Car using ANSYS Software

Nowadays, the demand for a high-speed car increases in which vehicle stability and fuel economy are the primary concern. The vehicle's aerodynamics plays a crucial role as it influences the overall performance of the vehicles. In the exploration of car aerodynamics, it involves studying various forces that act on a car while moving on the road, i.e., drag force, lift force. The leading causes of aerodynamic drag for automotive vehicles are the flow separation at the vehicles' rear end. By reducing the drag force, it is possible to increase the fuel economy. The research is focused on the effect of a vortex generator (VG) on a sedan car aerodynamics. The objective is to simulate fluid flow analysis for a sedan car that uses VG and without VG, to assess the effect of a different configuration of VG and the impact of a varying number of VG mounted on a sedan car in terms of flow pattern development and coefficient of drag (Cd). This study is conducted using two identical sedan car models, i.e., with VG and without VG. The flow around the vehicle has been considered incompressible. It is obtained by solving the incompressible form of the Reynolds Navier-Stokes (RANS) equations combined with the k-ε turbulence model. The simulation is run for different configuration of VG that acquire different radius of fillet, i.e., VG-1 (5 mm), VG-2 (30 mm) and VG-3 (50 mm) and for different number of VG that is mounted on a sedan car, i.e., 0 VG, 1 VG, 3 VG, 5 VG, 7 VG, and 9 VG. The data and results taken from this simulation show that the smallest fillet radius of VG, i.e., VG-1 (5 mm), is the best VG to be used on a sedan car. The results also show that, as the number of VG's increases, the drag coefficient is decreased. Hence, the best number of VG's to be used on a sedan car are nine VG's

CFD Simulation of Air-Piloted Downdraft Gasification Process: A Comparative Study Between Coal and Palm Kernel Shell as Feedstock

A fixed bed downdraft gasifier model based on computational fluid dynamic (CFD) framework was developed to investigate the influence of feedstock (palm kernel shell [PKS] and coal) on the quality of syngas produced via the gasification process. Euler–Euler approach was utilized in this study to describe the gas and solid phases. Realizable k-ε turbulence model was used to evaluate the constitutive properties of the dispersed phase and the gas phase behavior. This simulation model was validated by comparing the syngas composition of gasification simulation of coal with previous research, which yielded the overall accuracy result of 83.2%. This study also highlighted that PKS gasification produced 53.74% and 90.51% higher composition of H2 and CO respectively as compared to coal gasification. Whereas coal gasification produced 81.35%, 71.31% and 52.29% higher composition of CH4, H2O and CO2 respectively as compared to PKS gasification. Hence, PKS produced 66.2% higher combustible gas of H2 and CO than coal. PKS is thus considered as a potential renewable feedstock for gasification process as an alternative to the non-renewable coal. In addition, PKS gasification produced 52.29% lesser composition of CO2 as compared to coal gasification

CFD analysis on the effect of vortex generator on sedan car using ansys software

Nowadays, the demand for a high-speed car increases in which vehicle stability and fuel economy are the primary concern. The vehicle's aerodynamics plays a crucial role as it influences the overall performance of the vehicles. In the exploration of car aerodynamics, it involves studying various forces that act on a car while moving on the road, i.e., drag force, lift force. The leading causes of aerodynamic drag for automotive vehicles are the flow separation at the vehicles' rear end. By reducing the drag force, it is possible to increase the fuel economy. The research is focused on the effect of a vortex generator (VG) on a sedan car aerodynamics. The objective is to simulate fluid flow analysis for a sedan car that uses VG and without VG, to assess the effect of a different configuration of VG and the impact of a varying number of VG mounted on a sedan car in terms of flow pattern development and coefficient of drag (Cd). This study is conducted using two identical sedan car models, i.e., with VG and without VG. The flow around the vehicle has been considered incompressible. It is obtained by solving the incompressible form of the Reynolds Navier-Stokes (RANS) equations combined with the k-e turbulence model. The simulation is run for different configuration of VG that acquire different radius of fillet, i.e., VG-1 (5 mm), VG-2 (30 mm) and VG-3 (50 mm) and for different number of VG that is mounted on a sedan car, i.e., 0 VG, 1 VG, 3 VG, 5 VG, 7 VG, and 9 VG. The data and results taken from this simulation show that the smallest fillet radius of VG, i.e., VG-1 (5 mm), is the best VG to be used on a sedan car. The results also show that, as the number of VGs increases, the drag coefficient is decreased. Hence, the best number of VGs to be used on a sedan car are nine VGs

Rapid prototyping 3D model for PIV: Application in human trachea model flow analysis

Experimental works for analysing flow behaviour inside human trachea has become continuous problem as the model used to study cannot imitate the real geometry of human trachea structure. As the technology develop, Rapid Prototyping (RP) become more useful in constructing the 3D model that has complexity in their geometries. RP not only offer several technologies in developing the 3D model, but also varies type of materials that can be used to manufacture the 3D model. In this study, RP technique was chosen to develop the 3D model of human trachea to do the Particle Image Velocimetry (PIV) experimental works. Material used was Vero Clear due to PIV need a model that transparent so that visualization on flow inside the model can be seen and the velocity magnitude can be capture. The geometry was adapted from 60 years old trachea patient where the images of trachea was taken by using CT-scan. MIMICS software was used to extracted the images before reconstruct the trachea into 3D model. Velocity distribution was visualized and the magnitude were taken at both left and right bronchi. From the analysis, it concluded that the distribution of airflow to the second generation of trachea was 60:40 to right and left bronchi. It follows the rules as the right bronchi need to supply more air to the right lung compared to left as the volume of right lung bigger that left lung

Rapid Prototyping 30 Model for PIV: Application in Human Trachea Model Flow Analysis

Experimental works for analysing flow behaviour inside human trachea has become continuous problem as the model used to study cannot imitate the real geometry of human trachea structure. As the technology develop, Rapid Prototyping (RP) become more useful in constructing the 3D model that has complexity in their geometries. RP not only offer several technologies in developing the 3D model, but also varies type of materials that can be used to manufacture the 3D model. In this study, RP technique was chosen to develop the 3D model of human trachea to do the Particle Image Velocimetry (PIV) experimental works. Material used was Vero Clear due to PIV need a model that transparent so that visualization on flow inside the model can be seen and the velocity magnitude can be capture. The geometry was adapted from 60 years old trachea patient where the images of trachea was taken by using CT-scan. MIMICS software was used to extracted the images before reconstruct the trachea into 3D model. Velocity distribution was visualized and the magnitude were taken at both left and right bronchi. From the analysis, it concluded that the distribution of airflow to the second generation of trachea was 60:40 to right and left bronchi. It follows the rules as the right bronchi need to supply more air to the right lung compared to left as the volume of right lung bigger that left lung

Analysis on the flow and pressure distribution for actual stenosis in trachea

Knowledge of flow inside the human airway is very important for medical practitioner to make accurate diagnosis. With the presence stenosis inside the airway, the flow will be changed significantly and will directly affect the input to the main bronchi. In this study, patient-specific image is used and remodelled using computational fluid dynamic software to simulate the flow within the trachea. The image contains one stenosis which was then reconstructed to other locations. This procedure will enable the study of flow behaviour in the trachea with different stenosis locations. Emphasis of analysis is focused on the flow and pressure distribution along the main airway. For each model, computations were carried out in three different flow rates which are 15 l/min, 60 l/min and 100 l/min corresponding to regular human activity which are resting, normal and heavy excersice breathing, respectively. The results show as stenosis located at the upper third of the trachea, the pressure drop along the trachea are insignificant in every breathing condition but differ to the velocity where the maximum velocity is increase as the flow rate increase. For stenosis located at the lower third or the trachea, both pressure drop and velocity did effect clearly as the flow rate increase. The effect of different location of the stenosis on the velocity distribution along the centerline shows similar increment in every flow rate and the risk in breathing difficulties if the patient having a stenosis at the third location is three times higher compare to the first location if the patient in resting condition. It increases to five times higher when doing the regular activity and eight times higher if the patient doing heavy exercise. The comparison is based on the same size of the stenosis

The effect of different locations of tracheal stenosis to the flow characteristics using reconstructed CT-scanned image

The presence of tracheal stenosis would alter the flow path of the inhaled and exhaled air and subsequently changed the flow behavior inside the trachea and main bronchi. Therefore, it was our aim to investigate and predict the changes of flow behavior along with the pressure distribution with respect to the presence of stenosis on the tracheal lumen. In this study, actual CT scan images were extracted for flow modeling purposes. The images were then reconstructed to mimic the effect of different stenosis locations. This method overcomes the problem of the absence of actual images for different tracheal stenosis locations. The flow was subjected to different breathing situations corresponding to low, moderate and rigorous activities. The results showed that for flow over the stenosis farthest from the bifurcation, the pressure drop was insignificant for all breathing situations. At the same time, the inlet flow rate at the bifurcation showed less air flows into the right lung as compared to healthy flow conditions. On the other hand, for the flow over stenosis closest to the bifurcation, the pressure drop near the bifurcation area was very significant at high flow rate