Dr P K Dash | AMC Engineering College AMC Group of Institutions (original) (raw)

Papers by Dr P K Dash

1st International Conference on Advances in Aerospace and Navigation Systems – 2024 (iCAAN-2024), 2024

Hybrid rocket propulsion created a tremendous impact on rocketry after its inclusion in the rocke... more Hybrid rocket propulsion created a tremendous impact on rocketry after its inclusion in the rocket propulsion program. Simplicity, ease of handling, control of combustion, and ease of start and stop are some of the virtues of its rocket propulsion application. However, deficiencies in achieving the specific thrust and required energy for attaining that power have created concerns in the research domain about realizing such specific fuel consumption. In this paper, research has been demonstrated on various fuel compositions as one nature's product shellac and another one was with hydroxyl-terminated polybutadiene (HTPB) with one is one ratio. The laboratory-prepared fuel grain was studied in a static rocket motor using commercial oxygen gas as an oxidizer. The parameters like local regression rate, average regression rate, and average mass consumption rate with a selected mass flow rate of oxygen were evaluated and presented. Comparative results are demonstrated for virgin HTPB and HTPB with shellac in equal ratios with two different dimensions. The properties like heat of combustion were estimated using the bomb calorimetric method. All experimental data and simulated using theories are presented in the form of tables and figures for ready reference.

1st International Conference on Advances in Aerospace and Navigation Systems – 2024 (iCAAN-2024), 2024

Fatigue creates severe problems in aerospace vehicle failure during operation and research for th... more Fatigue creates severe problems in aerospace vehicle failure during operation and research for the aerospace community. With the advancement of aerospace materials, composites like Carbon fiber reinforced with epoxy matrix have found tremendous potential to overtake aircraft fatigue problems. This research presented the fatigue properties evaluation of bidirectional carbon composite in two different environmental areas. One is the virgin category and the other one is a water-effected category. Carbon epoxy composite laminate involved eight balanced bidirectional weaved layers of carbon fiber and epoxy resin fabricated by a vacuum molding method. The wellcured plates produced 1.68mm thick, and have 56% fiber volume fraction. Flat specimens as per ASTM-D-3039 standards were made for static test with proper quality inspection and dog-bone shape samples for fatigue test. A rotary bending fatigue testing machine was used to study the fatigue life of carbon/epoxy specimens. Tensile property and S-N curve were developed. The environmental damage and fatigue damage are recorded through photographic methods. All the results are presented through tables and figures for ready reference. Fatigue life assessment for bidirectional carbon/epoxy laminated composite is evaluated.

International Journal of Mechanical and Industrial Engineering, 2011

In the present study an effort is made to investigate the local regression rate, average regressi... more In the present study an effort is made to investigate the local regression rate, average regression rate through the effect of oxidizer injection pressure. For experimental investigation a lab scale ballistic test motor is designed and number of static test firing are carried out at different gaseous oxidizer injection pressure. The injection pressure is varied from 150psi to 420psi and a Swirl Injector and a conventional Shower Head Injector are used for the oxidizer injection from oxidizer chamber to fuel grain port. The local regression rate is obtained from the unburnt fuel web thickness after 10.5 second of test firing. Further, the investigation of regression rate of PVC and HTPB solid fuels are depended on mass flux of oxidizer as the regression rate shown a decreasing trend from head end to nozzle end. From the present analysis, it can be summarized that for PVC solid fuel regression rate is completely dependent on swirl injection of oxidizer, as well as the oxidizer injecti...

International Journal of Fracture, 1991

Linear Elastic Fracture Mechanics, LEFM, principles are successfully used to characterize the beh... more Linear Elastic Fracture Mechanics, LEFM, principles are successfully used to characterize the behavior of flawed structures and components under monotonic loading. Crack length increment, da, correlates with maximum stress intensity factor, K^, when the monotonic plastic zone size is small. Cracks can grow under cyclic loading even at stress levels lower than that required for crack extension under static loading. Paris et al. [1,2] established the correlation between crack growth rate, da/dN, and stress intensity factor range, delta-K, of the load cycle. Aplication of LEFM principles to crack extension under monotonic cyclic loading can be seen as:

Intermetallics, 2001

Chevron-notched beam (CNB) fracture toughness testing was conducted to examine the effects of env... more Chevron-notched beam (CNB) fracture toughness testing was conducted to examine the effects of environment such as air, vacuum ($1.3Â10 À4 Pa) and dry oxygen on fracture toughness of binary and ternary nickel silicide intermetallic alloys in the Ni-Si-Mg system. The results of testing indicate that environment appears to have little effect on the fracture toughness of these alloys. Regardless of environment the fracture toughness of single and multiphase alloys consisting of binary (

NMIT, 2019

Dear Professor, Greetings from NMIT! With due respect I bring to your kind notice that we are org... more Dear Professor,
Greetings from NMIT!
With due respect I bring to your kind notice that we are organizing 11th International Conference with main them ‘ERCAM’ (Engineering Research in Civil, Mechanical and Aerospace engineering). As a premier Institute in the field of Aerospace Engineering, I may request to receive some research papers from your esteemed organization.
Expecting for your acknowledgment and support to make this event more successful,
With best regards
Yours Sincerely

Dr. P K Dash

MATEC Web of Conferences, 2018

A Pulse Detonation Engine (PDE) is a new invented propulsion device that takes advantage of the p... more A Pulse Detonation Engine (PDE) is a new invented propulsion device that takes advantage of the pressure rise inherent to the efficient burning of fuel-air mixtures via detonations. Detonation initiation is a critical process that occurs in the cycle of a PDE. A practical method of detonation initiation is Deflagration-to-Detonation Transition (DDT), which describes the acceleration of a subsonic deflagration created using low initiation energies to a supersonic detonation. The DDT process is not well understood due to a wide range of time and length scales involving complex chemistry, turbulence and unsteady pressure waves. This paper discuss about the effects of blocking ratio in the augmentation of detonation pressure and velocity inside a cylindrical tube of diameter 0.0254m and a length of 1 m. The blockages are rectangular in shape placed at 2/3 rd distances of the length of the tube and the heights of the blockages are varied in terms of the diameter of the tube as 1/4 th , 1/3 rd , ½, 2/3 rd and 3/4 th the diameter of the tube. The setup is then analyzed in MATLAB using the physics of Friedlander's equation, which formulate the decay time duration of pressure across the tube length, with and without the blockage. Further, a 2D CFD analysis through ANSYS Workbench is conducted which gave the effective blocking ratio in a rectangular type of blockage placed at the 2/3 rd position of the length of the tube and the results are compared. For variable pressures ranging from 1 MPa to 100 MPa input, the effective pulse length is around 0.25 seconds after which the decay of pressure and temperature attain the critical limit. Also it is found that the maximum feasible velocity occurs for an inlet pressure of 10 MPa and 2/3 rd height of the blockage where the corresponding outlet velocity is 4692m/s and outlet total pressure being 10.542 MPa.

Materials Science and Engineering, 2018

Abstract: - Adhesively bonded joints are currently of interest to the aerospace field due to the ... more Abstract: - Adhesively bonded joints are currently of interest to the aerospace field due to the
heavy reliance on bonded composite structures in new aircraft designs. In response, tools for joints
analysis have been developed and examined. In this paper, the type of failure involved in single
adhesive lap joints of composite has been experimentally investigated. An acoustic emission
technique (AET) was used to monitor the pre and post aspects of damage growth in adhesive
composite joint in terms of strain energy released rate and sound amplitude dissipated. Criticality of
prior to failure was well assessed through acoustic waves monitoring method.

The growing use of plane-weave carbon fibre reinforced composite in aerospace components design d... more The growing use of plane-weave carbon fibre reinforced composite in aerospace components design demanded
to support and define the engineering concepts of durability and damage tolerance. After fatigue damage, the reliability
information in terms of flexure strength investigated in this paper. A series of three point flexure tests conducted over the
range of cyclic damaged specimens. The experimental results analysed with reference to residue strength and reduced
stiffness of the CFRC specimens. Fatigue damage followed by flexure tests produced significant strength reduction in
comparison to simple flexure tests, and the reduction in residual flexural strengths and stiffness purely depended on the
magnitude of fatigue stress applied with number of cycles subjected to bi-directional woven carbon/epoxy composite
specimens

The growing use of plane-weave carbon fiber reinforced composite in aerospace components design d... more The growing use of plane-weave carbon fiber reinforced composite in aerospace components design demanded to support and define the engineering concepts of durability and damage tolerance. After fatigue damage, the reliability information in terms of flexure strength investigated in this paper. A series of three point flexure tests conducted over the range of cyclic damaged specimens. The experimental results analyzed with reference to residue strength and reduced stiffness of the CFRC specimens. Fatigue damage followed by flexure tests produced significant strength reduction in comparison to simple flexure tests, and the reduction in residual flexural strengths and stiffness purelydepended on the magnitude of fatigue stress applied with number of cycles subjected to bi-directional woven carbon/epoxy composite specimens.

A spacecraft consists of a number of electronic packages to meet the desired functional requireme... more A spacecraft consists of a number of electronic packages to meet the desired functional requirements and in this, an electronic package is generally an assembly of printed circuit boards placed in a mechanical housing. A number of electronic components are mounted on the printed circuit board (PCB). A spacecraft experiences various types of loads during its launch such as vibration, acoustic and shock loads. Prediction of response for printed circuit boards due to vibration loads is important for mechanical design and reliability of electronic packages. The modelling and analysis of printed circuit boards are carried out for accurate prediction of response due to vibration loads using finite element method. A prediction about the vibration response of space bounded satellite's printed circuit board including the effect of component stiffness are coded using MatLab programming and the effect of contribution of component stiffness to the dynamic characteristics of PCB assembly is investigated. The analysis results are validated through vibration tests of PCB.

ARTICLE INFO ABSTRACT Swept wings are widely used in commercial Aircraft's to cruise at transonic... more ARTICLE INFO ABSTRACT Swept wings are widely used in commercial Aircraft's to cruise at transonic speeds with drag comparatively less than straight wings at transonic speed conditions. On the other hand trainer aircrafts both for commercial and defence trainings are preferred with swept wings to attain higher critical Mach speeds which is very less in straight wing trainer Aircraft's. Swept wings are preferred for its high lift to drag ratio low speed takeoff conditions and for near sonic flight operating conditions. Much research work on swept wings were done in past and many more are being carried out by different research centres around the globe and aircraft manufacturer's, but still the performance and aerodynamics of swept wings at transonic speeds and under different Turbulence levels and conditions is a grey area which needs to be addressed. In this paper two different configuration of swept wing (30 0 and 40 0 sweep) is analyzed and presented for two different Transonic speeds of 0.7 Mach and 0.9 Mach. The 3D wing model analyzed and presented in this paper is of NACA2412 profile. The lift and drag coefficient of this 3d wing at 0 0 AOA and at 4 0 AOA is tabulated in this paper for two of sweep angles 30 0 and 40 0. K-ω SST Turbulence model is used with Ansys Fluent as CFD software. The wing model is analyzed at four different Turbulence intensity levels of 2%, 5%, 10% and 15% and the results are tabulated. Pressure plot and Mach number plot of wing at symmetric section is shown at 0 0 and 4 0 AOA and at different operating speeds of 0.7 and 0.9Mach. High altitude environment conditions are considered for this analysis since the commercial aircraft and defence trainer aircrafts are meant to operate at high altitudes. Also an overview of the Swept wing flow instabilities and flow transitions are briefed in this paper.

Modern Aerospace Propulsion Technology are sizably oriented to develop the pulse detonation engin... more Modern Aerospace Propulsion Technology are sizably oriented to develop the pulse detonation engine for future era of hypersonic propulsion. In this paper, two-dimensional flame dynamic is analyzed in a close tube having 250cm long and 25cm dia. The blockages like semi-circular, triangular and rectangular at location like 1/3, ½ and 2/3 position of the tube length is used. Effect of blockage on transition of deflagration to detonation at different pressures input are studied. The stoichiometric kerosene-air mixture is an input during the analysis. Using commercial CFD software FLUENT and k-ε model, the results are analyzed in value of velocity changes at outlet due to presence of blockages. It is observed that the highest velocity in terms of detonation is seen in case of rectangular blockage at 2/3 length of the tube. All the outputs and comparative results are shown in form of figure and tables.

Adaptive high-resolution simulations of gaseous detonation using a hot-jet initiation were conduc... more Adaptive high-resolution simulations of gaseous detonation using a hot-jet initiation were conducted in supersonic combustible mixtures with spatially nonuniform species. The two-dimensional Euler equations were used as the governing equations in combination with a detailed hydrogen-oxygen reaction model. Three different groups of mixtures, which represent various degrees of chemical reactivity, were investigated. The results show that, when the mixtures generally have a high degree of chemical reactivity, detonation initiation can eventually be realized successfully by Mach reflection as well as the deflagration-to-detonation transition mechanism, independent of the spatial distribution of the mixtures in the channel. A recurring four-stage sequence of detonation initiation, detonation attenuation, initiation failure, and detonation reinitiation can be identified. When the mixtures generally have an intermediate degree of chemical reactivity, detonation combustion can be fully realized in the channel, where different overdrive degrees are found in the upper and lower halves. After the shutdown of the hot jet, the overdriven detonation attenuates gradually, and eventually a slightly overdriven detonation and a slightly underdriven detonation are generated, which can be regarded as a new stable state of propagation. However, whether a detonation can be initiated successfully is determined by the spatial mixture distribution. In mixtures with low degree of chemical reactivity, detonation initiation can generally not be realized. In this case, successful detonation initiation should be realizable by using of a stronger hot jet.

The main objective is to enhance the combustion process in the gas turbine engines using delta-wi... more The main objective is to enhance the combustion process in the gas turbine engines using delta-wing type vortex generators. This type of vortex generators are used to achieve rapid mixing through eddying motion of vortices which produce no recirculation zones and low pressure drop along the mixing plane. A detailed analysis of velocity vector, static pressure, and the intensity of turbulence generated by the single pair and double pair of vortex generators are presented as l/b ratio is varied. The results obtained through CFD analysis indicate that the optimum vortex generator configuration which produces maximum turbulence intensities with a less amount of recirculation zones at a relatively low pressure drop.

The main objective is to enhance the combustion process in the gas turbine engines using delta-wi... more The main objective is to enhance the combustion process in the gas turbine engines using delta-wing type vortex generators. This type of vortex generators are used to achieve rapid mixing through eddying motion of vortices which produce no recirculation zones and low pressure drop along the mixing plane. A detailed analysis of velocity vector, static pressure, and the intensity of turbulence generated by the single pair and double pair of vortex generators are presented as l/b ratio is varied. The results obtained through CFD analysis indicate that the optimum vortex generator configuration which produces maximum turbulence intensities with a less amount of recirculation zones at a relatively low pressure drop.

— The growing use of plane-weave carbon fibre reinforced composite in engineering components has ... more — The growing use of plane-weave carbon fibre reinforced composite in engineering components has really demanded to support and define the engineering concepts of durability and damage tolerance. A fatigue damage and reliability in forms of flexure strength is investigated in this paper. Three point flexure tests are performed over the range of cyclic damaged specimens. The experimental results are analyzed in the terms of reduced stiffness of the specimens. Fatigue damage followed by flexure test has shown significant strength reduction in comparison to simple flexure tests, and the reduction in residual flexural strength is depended on the magnitude of fatigue stress applied with number of cycles subjected..

Light aircraft are being used widely for passenger and freight transport nowadays. In this paper ... more Light aircraft are being used widely for passenger and freight transport nowadays. In this paper aerodynamics of a trainer aircraft's 3d wing with NACA 2412 aerofoil is presented. The lift and drag coefficient of the 3d wing at different angle's of attack plots of flow parameters like velocity, pressure and path lines are given. In this work kω sst Turbulence model is used to analyze the flow around the 3d wing of the trainer aircraft considering nominal wind t considered taking symmetry in to account. Fuselage is not considered in this work since the objective of this work is to predict the performance of wing alone. Trainer 240km/hr is simulated to compute lift and drag coefficients of the wing at different angle of attacks.

Light aircraft are being used widely for passenger and freight transport nowadays. In this paper ... more Light aircraft are being used widely for passenger and freight transport nowadays. In this paper aerodynamics of a trainer aircraft's 3d wing with NACA 2412 aerofoil is presented. The lift and drag coefficient of the 3d wing at different angle's of attack plots of flow parameters like velocity, pressure and path lines are given. In this work kω sst Turbulence model is used to analyze the flow around the 3d wing of the trainer aircraft considering nominal wind t considered taking symmetry in to account. Fuselage is not considered in this work since the objective of this work is to predict the performance of wing alone. Trainer 240km/hr is simulated to compute lift and drag coefficients of the wing at different angle of attacks.

1st International Conference on Advances in Aerospace and Navigation Systems – 2024 (iCAAN-2024), 2024

Hybrid rocket propulsion created a tremendous impact on rocketry after its inclusion in the rocke... more Hybrid rocket propulsion created a tremendous impact on rocketry after its inclusion in the rocket propulsion program. Simplicity, ease of handling, control of combustion, and ease of start and stop are some of the virtues of its rocket propulsion application. However, deficiencies in achieving the specific thrust and required energy for attaining that power have created concerns in the research domain about realizing such specific fuel consumption. In this paper, research has been demonstrated on various fuel compositions as one nature's product shellac and another one was with hydroxyl-terminated polybutadiene (HTPB) with one is one ratio. The laboratory-prepared fuel grain was studied in a static rocket motor using commercial oxygen gas as an oxidizer. The parameters like local regression rate, average regression rate, and average mass consumption rate with a selected mass flow rate of oxygen were evaluated and presented. Comparative results are demonstrated for virgin HTPB and HTPB with shellac in equal ratios with two different dimensions. The properties like heat of combustion were estimated using the bomb calorimetric method. All experimental data and simulated using theories are presented in the form of tables and figures for ready reference.

1st International Conference on Advances in Aerospace and Navigation Systems – 2024 (iCAAN-2024), 2024

Fatigue creates severe problems in aerospace vehicle failure during operation and research for th... more Fatigue creates severe problems in aerospace vehicle failure during operation and research for the aerospace community. With the advancement of aerospace materials, composites like Carbon fiber reinforced with epoxy matrix have found tremendous potential to overtake aircraft fatigue problems. This research presented the fatigue properties evaluation of bidirectional carbon composite in two different environmental areas. One is the virgin category and the other one is a water-effected category. Carbon epoxy composite laminate involved eight balanced bidirectional weaved layers of carbon fiber and epoxy resin fabricated by a vacuum molding method. The wellcured plates produced 1.68mm thick, and have 56% fiber volume fraction. Flat specimens as per ASTM-D-3039 standards were made for static test with proper quality inspection and dog-bone shape samples for fatigue test. A rotary bending fatigue testing machine was used to study the fatigue life of carbon/epoxy specimens. Tensile property and S-N curve were developed. The environmental damage and fatigue damage are recorded through photographic methods. All the results are presented through tables and figures for ready reference. Fatigue life assessment for bidirectional carbon/epoxy laminated composite is evaluated.

International Journal of Mechanical and Industrial Engineering, 2011

In the present study an effort is made to investigate the local regression rate, average regressi... more In the present study an effort is made to investigate the local regression rate, average regression rate through the effect of oxidizer injection pressure. For experimental investigation a lab scale ballistic test motor is designed and number of static test firing are carried out at different gaseous oxidizer injection pressure. The injection pressure is varied from 150psi to 420psi and a Swirl Injector and a conventional Shower Head Injector are used for the oxidizer injection from oxidizer chamber to fuel grain port. The local regression rate is obtained from the unburnt fuel web thickness after 10.5 second of test firing. Further, the investigation of regression rate of PVC and HTPB solid fuels are depended on mass flux of oxidizer as the regression rate shown a decreasing trend from head end to nozzle end. From the present analysis, it can be summarized that for PVC solid fuel regression rate is completely dependent on swirl injection of oxidizer, as well as the oxidizer injecti...

International Journal of Fracture, 1991

Linear Elastic Fracture Mechanics, LEFM, principles are successfully used to characterize the beh... more Linear Elastic Fracture Mechanics, LEFM, principles are successfully used to characterize the behavior of flawed structures and components under monotonic loading. Crack length increment, da, correlates with maximum stress intensity factor, K^, when the monotonic plastic zone size is small. Cracks can grow under cyclic loading even at stress levels lower than that required for crack extension under static loading. Paris et al. [1,2] established the correlation between crack growth rate, da/dN, and stress intensity factor range, delta-K, of the load cycle. Aplication of LEFM principles to crack extension under monotonic cyclic loading can be seen as:

Intermetallics, 2001

Chevron-notched beam (CNB) fracture toughness testing was conducted to examine the effects of env... more Chevron-notched beam (CNB) fracture toughness testing was conducted to examine the effects of environment such as air, vacuum ($1.3Â10 À4 Pa) and dry oxygen on fracture toughness of binary and ternary nickel silicide intermetallic alloys in the Ni-Si-Mg system. The results of testing indicate that environment appears to have little effect on the fracture toughness of these alloys. Regardless of environment the fracture toughness of single and multiphase alloys consisting of binary (

NMIT, 2019

Dear Professor, Greetings from NMIT! With due respect I bring to your kind notice that we are org... more Dear Professor,
Greetings from NMIT!
With due respect I bring to your kind notice that we are organizing 11th International Conference with main them ‘ERCAM’ (Engineering Research in Civil, Mechanical and Aerospace engineering). As a premier Institute in the field of Aerospace Engineering, I may request to receive some research papers from your esteemed organization.
Expecting for your acknowledgment and support to make this event more successful,
With best regards
Yours Sincerely

Dr. P K Dash

MATEC Web of Conferences, 2018

A Pulse Detonation Engine (PDE) is a new invented propulsion device that takes advantage of the p... more A Pulse Detonation Engine (PDE) is a new invented propulsion device that takes advantage of the pressure rise inherent to the efficient burning of fuel-air mixtures via detonations. Detonation initiation is a critical process that occurs in the cycle of a PDE. A practical method of detonation initiation is Deflagration-to-Detonation Transition (DDT), which describes the acceleration of a subsonic deflagration created using low initiation energies to a supersonic detonation. The DDT process is not well understood due to a wide range of time and length scales involving complex chemistry, turbulence and unsteady pressure waves. This paper discuss about the effects of blocking ratio in the augmentation of detonation pressure and velocity inside a cylindrical tube of diameter 0.0254m and a length of 1 m. The blockages are rectangular in shape placed at 2/3 rd distances of the length of the tube and the heights of the blockages are varied in terms of the diameter of the tube as 1/4 th , 1/3 rd , ½, 2/3 rd and 3/4 th the diameter of the tube. The setup is then analyzed in MATLAB using the physics of Friedlander's equation, which formulate the decay time duration of pressure across the tube length, with and without the blockage. Further, a 2D CFD analysis through ANSYS Workbench is conducted which gave the effective blocking ratio in a rectangular type of blockage placed at the 2/3 rd position of the length of the tube and the results are compared. For variable pressures ranging from 1 MPa to 100 MPa input, the effective pulse length is around 0.25 seconds after which the decay of pressure and temperature attain the critical limit. Also it is found that the maximum feasible velocity occurs for an inlet pressure of 10 MPa and 2/3 rd height of the blockage where the corresponding outlet velocity is 4692m/s and outlet total pressure being 10.542 MPa.

Materials Science and Engineering, 2018

Abstract: - Adhesively bonded joints are currently of interest to the aerospace field due to the ... more Abstract: - Adhesively bonded joints are currently of interest to the aerospace field due to the
heavy reliance on bonded composite structures in new aircraft designs. In response, tools for joints
analysis have been developed and examined. In this paper, the type of failure involved in single
adhesive lap joints of composite has been experimentally investigated. An acoustic emission
technique (AET) was used to monitor the pre and post aspects of damage growth in adhesive
composite joint in terms of strain energy released rate and sound amplitude dissipated. Criticality of
prior to failure was well assessed through acoustic waves monitoring method.

The growing use of plane-weave carbon fibre reinforced composite in aerospace components design d... more The growing use of plane-weave carbon fibre reinforced composite in aerospace components design demanded
to support and define the engineering concepts of durability and damage tolerance. After fatigue damage, the reliability
information in terms of flexure strength investigated in this paper. A series of three point flexure tests conducted over the
range of cyclic damaged specimens. The experimental results analysed with reference to residue strength and reduced
stiffness of the CFRC specimens. Fatigue damage followed by flexure tests produced significant strength reduction in
comparison to simple flexure tests, and the reduction in residual flexural strengths and stiffness purely depended on the
magnitude of fatigue stress applied with number of cycles subjected to bi-directional woven carbon/epoxy composite
specimens

The growing use of plane-weave carbon fiber reinforced composite in aerospace components design d... more The growing use of plane-weave carbon fiber reinforced composite in aerospace components design demanded to support and define the engineering concepts of durability and damage tolerance. After fatigue damage, the reliability information in terms of flexure strength investigated in this paper. A series of three point flexure tests conducted over the range of cyclic damaged specimens. The experimental results analyzed with reference to residue strength and reduced stiffness of the CFRC specimens. Fatigue damage followed by flexure tests produced significant strength reduction in comparison to simple flexure tests, and the reduction in residual flexural strengths and stiffness purelydepended on the magnitude of fatigue stress applied with number of cycles subjected to bi-directional woven carbon/epoxy composite specimens.

A spacecraft consists of a number of electronic packages to meet the desired functional requireme... more A spacecraft consists of a number of electronic packages to meet the desired functional requirements and in this, an electronic package is generally an assembly of printed circuit boards placed in a mechanical housing. A number of electronic components are mounted on the printed circuit board (PCB). A spacecraft experiences various types of loads during its launch such as vibration, acoustic and shock loads. Prediction of response for printed circuit boards due to vibration loads is important for mechanical design and reliability of electronic packages. The modelling and analysis of printed circuit boards are carried out for accurate prediction of response due to vibration loads using finite element method. A prediction about the vibration response of space bounded satellite's printed circuit board including the effect of component stiffness are coded using MatLab programming and the effect of contribution of component stiffness to the dynamic characteristics of PCB assembly is investigated. The analysis results are validated through vibration tests of PCB.

ARTICLE INFO ABSTRACT Swept wings are widely used in commercial Aircraft's to cruise at transonic... more ARTICLE INFO ABSTRACT Swept wings are widely used in commercial Aircraft's to cruise at transonic speeds with drag comparatively less than straight wings at transonic speed conditions. On the other hand trainer aircrafts both for commercial and defence trainings are preferred with swept wings to attain higher critical Mach speeds which is very less in straight wing trainer Aircraft's. Swept wings are preferred for its high lift to drag ratio low speed takeoff conditions and for near sonic flight operating conditions. Much research work on swept wings were done in past and many more are being carried out by different research centres around the globe and aircraft manufacturer's, but still the performance and aerodynamics of swept wings at transonic speeds and under different Turbulence levels and conditions is a grey area which needs to be addressed. In this paper two different configuration of swept wing (30 0 and 40 0 sweep) is analyzed and presented for two different Transonic speeds of 0.7 Mach and 0.9 Mach. The 3D wing model analyzed and presented in this paper is of NACA2412 profile. The lift and drag coefficient of this 3d wing at 0 0 AOA and at 4 0 AOA is tabulated in this paper for two of sweep angles 30 0 and 40 0. K-ω SST Turbulence model is used with Ansys Fluent as CFD software. The wing model is analyzed at four different Turbulence intensity levels of 2%, 5%, 10% and 15% and the results are tabulated. Pressure plot and Mach number plot of wing at symmetric section is shown at 0 0 and 4 0 AOA and at different operating speeds of 0.7 and 0.9Mach. High altitude environment conditions are considered for this analysis since the commercial aircraft and defence trainer aircrafts are meant to operate at high altitudes. Also an overview of the Swept wing flow instabilities and flow transitions are briefed in this paper.

Modern Aerospace Propulsion Technology are sizably oriented to develop the pulse detonation engin... more Modern Aerospace Propulsion Technology are sizably oriented to develop the pulse detonation engine for future era of hypersonic propulsion. In this paper, two-dimensional flame dynamic is analyzed in a close tube having 250cm long and 25cm dia. The blockages like semi-circular, triangular and rectangular at location like 1/3, ½ and 2/3 position of the tube length is used. Effect of blockage on transition of deflagration to detonation at different pressures input are studied. The stoichiometric kerosene-air mixture is an input during the analysis. Using commercial CFD software FLUENT and k-ε model, the results are analyzed in value of velocity changes at outlet due to presence of blockages. It is observed that the highest velocity in terms of detonation is seen in case of rectangular blockage at 2/3 length of the tube. All the outputs and comparative results are shown in form of figure and tables.

Adaptive high-resolution simulations of gaseous detonation using a hot-jet initiation were conduc... more Adaptive high-resolution simulations of gaseous detonation using a hot-jet initiation were conducted in supersonic combustible mixtures with spatially nonuniform species. The two-dimensional Euler equations were used as the governing equations in combination with a detailed hydrogen-oxygen reaction model. Three different groups of mixtures, which represent various degrees of chemical reactivity, were investigated. The results show that, when the mixtures generally have a high degree of chemical reactivity, detonation initiation can eventually be realized successfully by Mach reflection as well as the deflagration-to-detonation transition mechanism, independent of the spatial distribution of the mixtures in the channel. A recurring four-stage sequence of detonation initiation, detonation attenuation, initiation failure, and detonation reinitiation can be identified. When the mixtures generally have an intermediate degree of chemical reactivity, detonation combustion can be fully realized in the channel, where different overdrive degrees are found in the upper and lower halves. After the shutdown of the hot jet, the overdriven detonation attenuates gradually, and eventually a slightly overdriven detonation and a slightly underdriven detonation are generated, which can be regarded as a new stable state of propagation. However, whether a detonation can be initiated successfully is determined by the spatial mixture distribution. In mixtures with low degree of chemical reactivity, detonation initiation can generally not be realized. In this case, successful detonation initiation should be realizable by using of a stronger hot jet.

The main objective is to enhance the combustion process in the gas turbine engines using delta-wi... more The main objective is to enhance the combustion process in the gas turbine engines using delta-wing type vortex generators. This type of vortex generators are used to achieve rapid mixing through eddying motion of vortices which produce no recirculation zones and low pressure drop along the mixing plane. A detailed analysis of velocity vector, static pressure, and the intensity of turbulence generated by the single pair and double pair of vortex generators are presented as l/b ratio is varied. The results obtained through CFD analysis indicate that the optimum vortex generator configuration which produces maximum turbulence intensities with a less amount of recirculation zones at a relatively low pressure drop.

The main objective is to enhance the combustion process in the gas turbine engines using delta-wi... more The main objective is to enhance the combustion process in the gas turbine engines using delta-wing type vortex generators. This type of vortex generators are used to achieve rapid mixing through eddying motion of vortices which produce no recirculation zones and low pressure drop along the mixing plane. A detailed analysis of velocity vector, static pressure, and the intensity of turbulence generated by the single pair and double pair of vortex generators are presented as l/b ratio is varied. The results obtained through CFD analysis indicate that the optimum vortex generator configuration which produces maximum turbulence intensities with a less amount of recirculation zones at a relatively low pressure drop.

— The growing use of plane-weave carbon fibre reinforced composite in engineering components has ... more — The growing use of plane-weave carbon fibre reinforced composite in engineering components has really demanded to support and define the engineering concepts of durability and damage tolerance. A fatigue damage and reliability in forms of flexure strength is investigated in this paper. Three point flexure tests are performed over the range of cyclic damaged specimens. The experimental results are analyzed in the terms of reduced stiffness of the specimens. Fatigue damage followed by flexure test has shown significant strength reduction in comparison to simple flexure tests, and the reduction in residual flexural strength is depended on the magnitude of fatigue stress applied with number of cycles subjected..

Light aircraft are being used widely for passenger and freight transport nowadays. In this paper ... more Light aircraft are being used widely for passenger and freight transport nowadays. In this paper aerodynamics of a trainer aircraft's 3d wing with NACA 2412 aerofoil is presented. The lift and drag coefficient of the 3d wing at different angle's of attack plots of flow parameters like velocity, pressure and path lines are given. In this work kω sst Turbulence model is used to analyze the flow around the 3d wing of the trainer aircraft considering nominal wind t considered taking symmetry in to account. Fuselage is not considered in this work since the objective of this work is to predict the performance of wing alone. Trainer 240km/hr is simulated to compute lift and drag coefficients of the wing at different angle of attacks.

Light aircraft are being used widely for passenger and freight transport nowadays. In this paper ... more Light aircraft are being used widely for passenger and freight transport nowadays. In this paper aerodynamics of a trainer aircraft's 3d wing with NACA 2412 aerofoil is presented. The lift and drag coefficient of the 3d wing at different angle's of attack plots of flow parameters like velocity, pressure and path lines are given. In this work kω sst Turbulence model is used to analyze the flow around the 3d wing of the trainer aircraft considering nominal wind t considered taking symmetry in to account. Fuselage is not considered in this work since the objective of this work is to predict the performance of wing alone. Trainer 240km/hr is simulated to compute lift and drag coefficients of the wing at different angle of attacks.

International Conference on Emerging research in Aeronautical Engineering ERCAM -2019

The growing use of plane-weave carbon fiber reinforced composite in aerospace components design d... more The growing use of plane-weave carbon fiber reinforced composite in aerospace components design demanded to support and define the engineering concepts of durability and damage tolerance. After fatigue damage, the reliability information in terms of flexure strength investigated in this paper. A series of three point flexure tests conducted over the range of cyclic damaged specimens. The experimental results analyzed with reference to residue strength and reduced stiffness of the CFRC specimens. Fatigue damage followed by flexure tests produced significant strength reduction in comparison to simple flexure tests, and the reduction in residual flexural strengths and stiffness purelydepended on the magnitude of fatigue stress applied with number of cycles subjected to bi-directional woven carbon/epoxy composite specimens.

Aircraft's both for combat and civil purpose work under different environment conditions, especia... more Aircraft's both for combat and civil purpose work under different environment conditions, especially when it is a combat Aircraft or a jet trainer it will be more often subjected to high level of turbulence due to max manoeuvring and shorter runway takeoff operations. The environment conditions at which civil and combat aircraft operates are unpredictable and will change from one location to other based on weather and climate conditions. In this paper the lift and drag coefficient of a finite 3D wing of a subsonic Aircraft is presented at transonic speed conditions and at different turbulence intensity levels. 3D wing is of NACA 2412 profile. The results obtained by this work on subsonic wing can be used to compare the performance of this subsonic wing with respect to performance of Transonic and supersonic wings. A overview of Transonic aerodynamics and the Turbulence model used is presented in this paper. This subsonic wing is analyzed using K-ω SST Turbulence model and for two different AOA of 0 0 and 4 0. The Mach number of flow over the wing and the pressure plot at the wing symmetric plane at different aircraft speed and at different turbulence intensity levels are discussed in this paper. CFD software Ansys Fluent is used to analyze the aircraft wing at two different AOA and at two different transonic speeds.

— Modern Aerospace Propulsion Technology are currently concentrating to develop the pulse detonat... more — Modern Aerospace Propulsion Technology are currently concentrating to develop the pulse detonation engine as futuristic hypersonic propulsion. In this paper, two-dimensional kerosene/oxygen flame dynamic is analyzed in a close tube having 250cm long and 25cm dia. The blockages like hemisphere pyramid and cube at location of 1/3, ½ and 2/3 length of the tube is used. Blockage effects on transition of deflagration flame wave to detonation at different pressures input are studied. The stoichiometric kerosene-air mixture is considered as an input of composition with its properties. Using commercial CFD software FLUENT and k-ε model, the simulations are carried out and analyzed in terms of velocity changes at outlet due to presence of blockages. It is observed that the highest velocity of detonation is seen in case of rectangular blockage at 2/3 length of the tube. All the outputs and comparative results are shown in form of figure and tables and successfully analyzed.