yagya dutta Dwivedi | GITAM UNIVERSITY, HYDERABAD, INDIA (original) (raw)
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Papers by yagya dutta Dwivedi
Numerical aero-acoustic analysis of wind turbine blades is conducted on three different sized mac... more Numerical aero-acoustic analysis of wind turbine blades is conducted on three different sized machines 350kW, 2MW &3MW. The turbine blade is considered as independent noise source and sound pressure levels produced from airfoil self-noise are assessed according to the BPM model. This model is semi empirical and predicts the sound pressure levels for 1/3 rd octave band frequencies 20Hz – 10kHz range. The frequency spectra of noise mechanism components for untripped boundary layer and directivity pattern as function of observer distance is illustrated. Model sensitivity is calculated using the directivity at several octave band frequencies and observer azimuth positions. The total sound pressure levels for the turbines are compared with theoretical predictions.
This paper investigates the aerodynamics characteristic of the wing and the different winglets. A... more This paper investigates the aerodynamics characteristic of the wing and the different winglets. A winglet is vertical surface placed at the tip of the wing, this helps to increase the aerodynamic efficiency of the wing. The airfoil used to construct the whole wing is NACA 4412.The wing and winglets are manufactured by using Fiber glass re-enforced composite materials (FRCM). The three types of winglets such as blended, bird like winglet and finlet were analyzed in this work. The wing and winglets model were made by using CATIA V5. The experimental analysis was carried out in a low speed subsonic wind tunnel, having a cross section of 0.300 m X 0.300 m X 0.600 m, at a velocity of 25 m/s and 40 m/s. The winglets have been experimentally tested at different Cant angles and angles of attack. The results of this experiment shows that the finlet type of winglet tend to delay the stall, bird winglet is efficient at low speed, and overall the blended winglet was more efficient than the other two types of winglets.
Numerical aero-acoustic analysis of wind turbine blades is conducted on three different sized mac... more Numerical aero-acoustic analysis of wind turbine blades is conducted on three different sized machines 350kW, 2MW &3MW. The turbine blade is considered as independent noise source and sound pressure levels produced from airfoil self-noise are assessed according to the BPM model. This model is semi empirical and predicts the sound pressure levels for 1/3 rd octave band frequencies 20Hz – 10kHz range. The frequency spectra of noise mechanism components for untripped boundary layer and directivity pattern as function of observer distance is illustrated. Model sensitivity is calculated using the directivity at several octave band frequencies and observer azimuth positions. The total sound pressure levels for the turbines are compared with theoretical predictions.
In the present commercial air transport scenario, efficient, economically and attractive configur... more In the present commercial air transport scenario, efficient, economically and attractive configurations are urgently needed. Studies have shown remarkable performance improvements for the Blended-Wing-Body (BWB) over conventional subsonic transport. The objective of this research is to assess the aerodynamic performance of a giant size, Blended Wing Body layout, which is expected to have many advantaged over the conventional airplane. To this end, the 3D CAD scaled model of BWB was prepared using commercial modeling software CATIA V5 and flow simulation is done by using ANSYS FLUENT finite volume analysis simulation tool. The center-body of BWB was made with NACA 0012-64, and inner and outer wing was made from supercritical airfoil of NACA S (2) 0710. The tetrahedron 3D meshing is done by ICEM CFD, Spalars-Almaras one equation turbulence modeling is used to consider the turbulence. The results showed that the performance and range of this tested model found highest at 20 0 angels of attack and glide, endurance and sink rate performance found highest at 25 0 angels of attack. These parameters are higher compared to existing conventional transport aircrafts.
In the present commercial air transport scenario, efficient, economically and attractive configur... more In the present commercial air transport scenario, efficient, economically and attractive configurations are urgently needed. Studies have shown remarkable performance improvements for the Blended-Wing-Body (BWB) over conventional subsonic transport. The objective of this research is to assess the aerodynamic performance of a giant size, Blended Wing Body layout, which is expected to have many advantaged over the conventional airplane. To this end, the 3D CAD scaled model of BWB was prepared using commercial modeling software CATIA V5 and flow simulation is done by using ANSYS FLUENT finite volume analysis simulation tool. The center-body of BWB was made with NACA 0012-64, and inner and outer wing was made from supercritical airfoil of NACA S (2) 0710. The tetrahedron 3D meshing is done by ICEM CFD, Spalars-Almaras one equation turbulence modeling is used to consider the turbulence. The results showed that the performance and range of this tested model found highest at 20 0 angels of attack and glide, endurance and sink rate performance found highest at 25 0 angels of attack. These parameters are higher compared to existing conventional transport aircrafts.
... more
Determination of pressure distribution on airfoil profiles enables to understand the dynamic flow... more Determination of pressure distribution on airfoil profiles enables to understand the dynamic flow characteristics around the surface of wings or blades. Computational methods are widely applied in the field of aerodynamics to predict the aerodynamic characteristics such as the pressure, lift and drag coefficients on an airfoil. In the present paper, the pressure distribution of NACA airfoil profiles is calculated using the numerical panel method for 2D lifting air flow conditions. The analysis of airfoil geometry subjected to various AOA (angle of attack) including the stalling angles is considered to observe the variation in pressure coefficients along the chord. The zero lift AOA for the profiles are also evaluated in order to assess influence of thickness to chord ratios on airfoil characteristics.
This material gives a basic aerodynamics related to rotor craft systems. This is a basic theory b... more This material gives a basic aerodynamics related to rotor craft systems. This is a basic theory behind the helicopter blades. How the relative wing is affecting during hover, transnational flight, vertical flight. The theory also gives idea about the ground effect on rotor blades at different conditions.
Abstract— The goal of this research project was to test the aerodynamic parameters like lift, dra... more Abstract—
The goal of this research project was to test the
aerodynamic parameters like lift, drag, L\D ratio
and also the
pressure distribution on two authentic birds’
wings i.e. pigeon
and parrot
.The main purpose of using two different birds' wings
is to study the effectiveness of wing span and area, in their flight.
This analysis was made using digital subsonic wind tunnel.
Consequently it is necessary for
us
to study about aircraft flight
with an emphasis on bird flight. As per the given theoretical
results the lift and drag varied for both the birds. Though both
the birds have the same ability to flap, for generating lift, the
aerodynamic parameters varied because they had different
velocities,
and where adjusted at different angles of attack.
The
study of bird wing also gives the concept of alula which plays the
major role and helps the bird to fly. It is a sensory anti-stalling
structure and its activity depends on its shape and air pressure.
In the present analysis the airflow over the bird’s wings of
pigeon and parrot with alula locked and unlocked was tested. On
comparing it was found that the lift for the parrot’s wing is
greater than that of the pigeon, with the alula open and closed.
The pressure distribution varied for both the birds considerably
with varying angle of attack having its alula unlock. The results
are found to be good so as to benefit the mankind in perceptive of the bird flight and advances in aircraft technology
Abstract: Modern society requires a variety of goods and services which require energy as the div... more Abstract: Modern society requires a variety of goods and services which require energy as the diversity of range of services increases so is the demand for energy. Electrical energy because of its versatility takes major share. Coal has to be transported to thermal stations located away from coalfields by railways and power has to be transmitted over large distances from pithead stations. These problems can be eliminated or reduced by converting coal into SNG (synthetic natural gas) at pithead and transporting the gas by pipe-grid to all thermal stations. The efficiency of power station can be increased by adopting combined cycle. Eco-friendly MHD (Thermal Cell) generator is now suggested for development as a topping addition for combined cycle to further improve the efficiency. Keywords: Coal, MHD Generator, Thermal Cell, Synthetic Natural Gas (SNG), Combined Cycle
Numerical aero-acoustic analysis of wind turbine blades is conducted on three different sized mac... more Numerical aero-acoustic analysis of wind turbine blades is conducted on three different sized machines 350kW, 2MW &3MW. The turbine blade is considered as independent noise source and sound pressure levels produced from airfoil self-noise are assessed according to the BPM model. This model is semi empirical and predicts the sound pressure levels for 1/3 rd octave band frequencies 20Hz – 10kHz range. The frequency spectra of noise mechanism components for untripped boundary layer and directivity pattern as function of observer distance is illustrated. Model sensitivity is calculated using the directivity at several octave band frequencies and observer azimuth positions. The total sound pressure levels for the turbines are compared with theoretical predictions.
This paper investigates the aerodynamics characteristic of the wing and the different winglets. A... more This paper investigates the aerodynamics characteristic of the wing and the different winglets. A winglet is vertical surface placed at the tip of the wing, this helps to increase the aerodynamic efficiency of the wing. The airfoil used to construct the whole wing is NACA 4412.The wing and winglets are manufactured by using Fiber glass re-enforced composite materials (FRCM). The three types of winglets such as blended, bird like winglet and finlet were analyzed in this work. The wing and winglets model were made by using CATIA V5. The experimental analysis was carried out in a low speed subsonic wind tunnel, having a cross section of 0.300 m X 0.300 m X 0.600 m, at a velocity of 25 m/s and 40 m/s. The winglets have been experimentally tested at different Cant angles and angles of attack. The results of this experiment shows that the finlet type of winglet tend to delay the stall, bird winglet is efficient at low speed, and overall the blended winglet was more efficient than the other two types of winglets.
Numerical aero-acoustic analysis of wind turbine blades is conducted on three different sized mac... more Numerical aero-acoustic analysis of wind turbine blades is conducted on three different sized machines 350kW, 2MW &3MW. The turbine blade is considered as independent noise source and sound pressure levels produced from airfoil self-noise are assessed according to the BPM model. This model is semi empirical and predicts the sound pressure levels for 1/3 rd octave band frequencies 20Hz – 10kHz range. The frequency spectra of noise mechanism components for untripped boundary layer and directivity pattern as function of observer distance is illustrated. Model sensitivity is calculated using the directivity at several octave band frequencies and observer azimuth positions. The total sound pressure levels for the turbines are compared with theoretical predictions.
In the present commercial air transport scenario, efficient, economically and attractive configur... more In the present commercial air transport scenario, efficient, economically and attractive configurations are urgently needed. Studies have shown remarkable performance improvements for the Blended-Wing-Body (BWB) over conventional subsonic transport. The objective of this research is to assess the aerodynamic performance of a giant size, Blended Wing Body layout, which is expected to have many advantaged over the conventional airplane. To this end, the 3D CAD scaled model of BWB was prepared using commercial modeling software CATIA V5 and flow simulation is done by using ANSYS FLUENT finite volume analysis simulation tool. The center-body of BWB was made with NACA 0012-64, and inner and outer wing was made from supercritical airfoil of NACA S (2) 0710. The tetrahedron 3D meshing is done by ICEM CFD, Spalars-Almaras one equation turbulence modeling is used to consider the turbulence. The results showed that the performance and range of this tested model found highest at 20 0 angels of attack and glide, endurance and sink rate performance found highest at 25 0 angels of attack. These parameters are higher compared to existing conventional transport aircrafts.
In the present commercial air transport scenario, efficient, economically and attractive configur... more In the present commercial air transport scenario, efficient, economically and attractive configurations are urgently needed. Studies have shown remarkable performance improvements for the Blended-Wing-Body (BWB) over conventional subsonic transport. The objective of this research is to assess the aerodynamic performance of a giant size, Blended Wing Body layout, which is expected to have many advantaged over the conventional airplane. To this end, the 3D CAD scaled model of BWB was prepared using commercial modeling software CATIA V5 and flow simulation is done by using ANSYS FLUENT finite volume analysis simulation tool. The center-body of BWB was made with NACA 0012-64, and inner and outer wing was made from supercritical airfoil of NACA S (2) 0710. The tetrahedron 3D meshing is done by ICEM CFD, Spalars-Almaras one equation turbulence modeling is used to consider the turbulence. The results showed that the performance and range of this tested model found highest at 20 0 angels of attack and glide, endurance and sink rate performance found highest at 25 0 angels of attack. These parameters are higher compared to existing conventional transport aircrafts.
... more
Determination of pressure distribution on airfoil profiles enables to understand the dynamic flow... more Determination of pressure distribution on airfoil profiles enables to understand the dynamic flow characteristics around the surface of wings or blades. Computational methods are widely applied in the field of aerodynamics to predict the aerodynamic characteristics such as the pressure, lift and drag coefficients on an airfoil. In the present paper, the pressure distribution of NACA airfoil profiles is calculated using the numerical panel method for 2D lifting air flow conditions. The analysis of airfoil geometry subjected to various AOA (angle of attack) including the stalling angles is considered to observe the variation in pressure coefficients along the chord. The zero lift AOA for the profiles are also evaluated in order to assess influence of thickness to chord ratios on airfoil characteristics.
This material gives a basic aerodynamics related to rotor craft systems. This is a basic theory b... more This material gives a basic aerodynamics related to rotor craft systems. This is a basic theory behind the helicopter blades. How the relative wing is affecting during hover, transnational flight, vertical flight. The theory also gives idea about the ground effect on rotor blades at different conditions.
Abstract— The goal of this research project was to test the aerodynamic parameters like lift, dra... more Abstract—
The goal of this research project was to test the
aerodynamic parameters like lift, drag, L\D ratio
and also the
pressure distribution on two authentic birds’
wings i.e. pigeon
and parrot
.The main purpose of using two different birds' wings
is to study the effectiveness of wing span and area, in their flight.
This analysis was made using digital subsonic wind tunnel.
Consequently it is necessary for
us
to study about aircraft flight
with an emphasis on bird flight. As per the given theoretical
results the lift and drag varied for both the birds. Though both
the birds have the same ability to flap, for generating lift, the
aerodynamic parameters varied because they had different
velocities,
and where adjusted at different angles of attack.
The
study of bird wing also gives the concept of alula which plays the
major role and helps the bird to fly. It is a sensory anti-stalling
structure and its activity depends on its shape and air pressure.
In the present analysis the airflow over the bird’s wings of
pigeon and parrot with alula locked and unlocked was tested. On
comparing it was found that the lift for the parrot’s wing is
greater than that of the pigeon, with the alula open and closed.
The pressure distribution varied for both the birds considerably
with varying angle of attack having its alula unlock. The results
are found to be good so as to benefit the mankind in perceptive of the bird flight and advances in aircraft technology
Abstract: Modern society requires a variety of goods and services which require energy as the div... more Abstract: Modern society requires a variety of goods and services which require energy as the diversity of range of services increases so is the demand for energy. Electrical energy because of its versatility takes major share. Coal has to be transported to thermal stations located away from coalfields by railways and power has to be transmitted over large distances from pithead stations. These problems can be eliminated or reduced by converting coal into SNG (synthetic natural gas) at pithead and transporting the gas by pipe-grid to all thermal stations. The efficiency of power station can be increased by adopting combined cycle. Eco-friendly MHD (Thermal Cell) generator is now suggested for development as a topping addition for combined cycle to further improve the efficiency. Keywords: Coal, MHD Generator, Thermal Cell, Synthetic Natural Gas (SNG), Combined Cycle