aqib khan - Academia.edu (original) (raw)

Papers by aqib khan

Research paper thumbnail of Shock detachment in granular flows

Proceedings of the 32nd International Symposium on Shock Waves (ISSW32 2019)

Research paper thumbnail of A numerical investigation of granular shock waves over a circular cylinder using the discrete element method

Journal of Fluid Mechanics

Numerical simulation based on the discrete element method (DEM) is used to investigate the flow f... more Numerical simulation based on the discrete element method (DEM) is used to investigate the flow field generated when a cylindrical obstacle is placed in a supersonic granular stream. Robust validation of the simulation model is performed by comparing numerical results with experiments. Experiments are performed using a two-dimensional set-up generating rapid granular flow owing to gravity. DEM simulations demonstrate that a rapid gas-like stream of grains suddenly decelerates across the shock wave and finally collapses into a slow-moving heap at the cylinder. The volume fraction suddenly increases across the shock layer and remains constant thereafter. The flow physics of the shock wave and the granular heap is elucidated through fundamental fluid dynamic quantities such as the velocity, volume fraction, pressure and granular temperature. It is shown that the interaction of grains with a cylindrical obstacle results in the generation of pressure, which is responsible for sustaining ...

Research paper thumbnail of Design and Analysis of Hand Gesture Controlled Quadcopter

2020 IEEE 23rd International Multitopic Conference (INMIC)

Hand control quadcopter, which is control of the motion of the hand. The user needs to wear a glo... more Hand control quadcopter, which is control of the motion of the hand. The user needs to wear a glove, which incorporates the sensors. The sensors will record the development of the movement in a particular direction, which will result in the development of the quad copter in that individual direction. The quad copter and hand motion glove are associated wirelessly by means of RF waves. The wireless correspondence empowers the user to cooperate with the quad copter in a friendlier manner. This project structured a quadcopter framework utilizing an ardupiolt mega2.8 chip with an RF transmitter with a few live control shapes accessible just as a mission organizer for autopilot control.

Research paper thumbnail of Rural Electrification through an Optimized Off-grid Microgrid based on Biogas, Solar, and Hydro Power

2020 International Conference on Engineering and Emerging Technologies (ICEET)

Renewable energy is the only solution to the problem of depleting environmental conditions and en... more Renewable energy is the only solution to the problem of depleting environmental conditions and energy shortage. Animal manure is a major output waste of rural areas and it can be converted into biogas through anaerobic digestion. Biogas is mainly CH4 which is combustible and can be used as fuel. In Pakistan, most of the rural population is relying on agriculture and cattle farming. Agriculture gives us hydro potential and cattle farming gives us biogas. And both of these resources, if used properly, can drastically improve the socioeconomic condition of rural areas. The sub-rural tehsil of Division Bahawalpur, “Mandi Yazman” is considered as a study area with the domestic load. This paper gives a techno-economic analysis of microgrid based on biogas, solar and hydropower to find out the best possible combination for lowest COE (cost of energy) and NPC (net present cost) according to the available resources in the proposed site.

Research paper thumbnail of Unit-19 Linkage in the Trade

Research paper thumbnail of Effect of Cross-Wire Tab Offset on Twin-Jet Mixing Characteristics

Proceedings of the 32nd International Symposium on Shock Waves (ISSW32 2019), 2019

Research paper thumbnail of Block-6 Development of travel and Tourism

Research paper thumbnail of Unit-5 Pilgrimage

Research paper thumbnail of Unit-20 Threats and Obstacles to Tourism

Research paper thumbnail of Unit-2 Understanding Tourism-II

Research paper thumbnail of Unit-3 Use of History

Research paper thumbnail of Parametric study and scaling of Mach 1.5 jet manipulation using steady fluidic injection

Physics of Fluids, 2022

We present the experimental investigation conducted to study the mixing characteristics of a Mach... more We present the experimental investigation conducted to study the mixing characteristics of a Mach 1.5 jet manipulation using steady fluidic injection. Two important parameters are investigated, namely, the number of injectors, N, and the mass flow rate ratio of the injector jet to the main jet, Cm, along with the expansion ratio of the main jet, [Formula: see text], where pe and pa are the nozzle exit and atmospheric pressures, respectively. The jet mixing quantified as a measure of supersonic core length, [Formula: see text], strongly depends on N, Cm, and [Formula: see text]. Two distinct regions behind the jet manipulation are identified, and a physical reasoning based on [Formula: see text] is presented using Pitot pressure measurements and Schlieren images. Empirical scaling analysis conducted on the experimental data for [Formula: see text] = f1( N, Cm, [Formula: see text], [Formula: see text]) is reduced to [Formula: see text] = [Formula: see text], where MRN is the momentum...

Research paper thumbnail of Performance Evaluation of Third Harmonic Injection PWM Technique for Three Phase Multilevel Inverter

2021 International Conference on Frontiers of Information Technology (FIT), 2021

Sensitivity of power system to various factors, such as voltage sags/swells and harmonics, has be... more Sensitivity of power system to various factors, such as voltage sags/swells and harmonics, has been increasing with rapid increase in automation. This study focuses on the reduction of harmonics of a three-phase Cascaded H-Bridge Multilevel Inverter (CHB-MLI) with Field Oriented Control (FOC) using the Third Harmonic Injection (THIPWM) technique. The aim is to increase the maximum utilization of DC bus along with the reduction of Total Harmonic Distortion (THD). The proposed design of MLI with THIPWM is compared with conventional techniques by taking THD into account for different types of loads. This research utilized MATLAB/Simulink as simulating, modelling and analyzing tool.

Research paper thumbnail of Detachment of strong shocks in confined granular flows

Journal of Fluid Mechanics, 2022

Granular flows are highly dissipative due to frictional resistance and inelasticity in collisions... more Granular flows are highly dissipative due to frictional resistance and inelasticity in collisions among grains. They are known to exhibit shock waves at velocities that are easily achieved in industrial and nature-driven flows such as avalanches and landslides. This experimental work investigates the formation of strong shock waves on triangular obstacles placed in a dry rapid granular stream in a confined two-dimensional set-up. Oblique attached shock waves are formed for mild turning angles and higher flow velocities, whereas strong bow shock waves are formed for higher turning angles and slower granular streams. A shadowgraph imaging technique elucidates interesting characteristics of the shock waves, especially in the vicinity of shock detachment. Velocity distributions in the form of scatter plots and probability distribution functions are calculated from the flow field data obtained by particle imaging velocimetry. The flow field around the granular shock wave region represent...

Research paper thumbnail of Optimized and Feasible Sustainable Energy System for Remotes Areas in Sindh by Utilizing HOMER

2020 IEEE 23rd International Multitopic Conference (INMIC), 2020

The utilization of sustainable power source is expanding everywhere throughout the world. This re... more The utilization of sustainable power source is expanding everywhere throughout the world. This research talked about the feasibility of giving power by utilizing hybrid sustainable power system to a far off small village, the populace of 15 families with a normal of five to six members in each family. The region of study, Kandhkot located in the Sindh, Pakistan. In the current scenarios, day by day vitality utilization of 500 kWh and a peak maximum load of 104 kW were taken into account. This research paper shows an approach to study different situations of sustainable power source system based on the economy, production of power, design, control, biomass accessibility and emissions of pollution. The HOMER programming software is utilized to completely simulate various situations. The output of this analysis demonstrates that the value of maximum capacity per year increases, the total present expense and levelized cost of vitality diminishes. The analysis of sensitivity parameters demonstrated that this design is the only optimized practical system under given varieties of various parameters.

Research paper thumbnail of A Study of State Feedback controllers for Pole Placement

2018 5th International Multi-Topic ICT Conference (IMTIC), 2018

A comprehensive study for pole placement of DC motor is studied using different state feedback co... more A comprehensive study for pole placement of DC motor is studied using different state feedback control techniques. It also compares the control parameters performance of the state feedback(SFB), feed-forward gain with state feedback(FFG-SFB) and integral control with State feedback controller(ICSFB). Ackermann’s formula being used for pole placement techniques. Performance level is based on the parameter of settling time, percentage overshoots and steady state error. The performance parameters are validated using Matlab/Simulink software.

Research paper thumbnail of An Optimized Off-gird Renewable AC/DC Microgrid for Remote Communities of Pakistan

2019 International Conference on Electrical, Communication, and Computer Engineering (ICECCE), 2019

Supplying electricity to rural areas can improve the socio-economic status of remote communities.... more Supplying electricity to rural areas can improve the socio-economic status of remote communities. Today, renewable energy technologies are the most focused research areas as they can play an important role in improving the quality of life by meeting the electricity demand. Indigenous renewable energy resources (RES) in these remote areas can be used to form a hybrid system that meets the electrical requirements of the community. This research explores a variety of hybrid and renewable energy systems (HRES) based on solar and wind resources to meet diverse community needs. The remote area of Pindiali (Latitude: 34 degrees 27.29 minutes North, Longitude 71 degrees 27.22 minutes East) in the Mohmand District of Pakistan is considered a study area. The system is designed and analyzed with anticipated load requirements and existing energy resources using HOMER software. The proposed system has a very low cost of energy (i.e., 0.166 $/kWh). The suggested solar wind hybrid system (SWHS) can be easily adapted to other areas of the globe with alike climates.

Research paper thumbnail of Soil stabilization using polypropylene

Submitted in partial fulfilment of the requirements for the degree of Bachelor of Civil Engineering

Research paper thumbnail of Interfacial Waves in Dual Stream Granular Flows

Research paper thumbnail of Experimental investigation of the effect of cross wire on the flow field of elliptic jet

International Journal of Heat and Fluid Flow, 2021

Abstract The effectiveness of cross wire in controlling the mixing characteristics of a circular ... more Abstract The effectiveness of cross wire in controlling the mixing characteristics of a circular and an equivalent elliptic jet is investigated experimentally. While circular jets are conventional, elliptic jets have gained attention due to their better mixing characteristics and faster decay. To further explore and augment the capabilities of elliptic jets for practical utility, it is investigated whether using an elliptic jet with cross wire control gives additional benefit in terms of mixing enhancement over an axisymmetric jet. Experiments are performed for subsonic and choked flow conditions with nozzle pressure ratios ranging from 1.2 to 7.0 . Time-averaged pitot pressures and schlieren visualization is used for diagnosis. The jet bifurcation can be seen in controlled elliptical jets at all nozzle pressure ratios (NPRs). Core length is reduced to as much as 70 % in the elliptical jet and 84 % in the case of the circular jet. The core length values estimated from the present data are compared with the previous investigations.

Research paper thumbnail of Shock detachment in granular flows

Proceedings of the 32nd International Symposium on Shock Waves (ISSW32 2019)

Research paper thumbnail of A numerical investigation of granular shock waves over a circular cylinder using the discrete element method

Journal of Fluid Mechanics

Numerical simulation based on the discrete element method (DEM) is used to investigate the flow f... more Numerical simulation based on the discrete element method (DEM) is used to investigate the flow field generated when a cylindrical obstacle is placed in a supersonic granular stream. Robust validation of the simulation model is performed by comparing numerical results with experiments. Experiments are performed using a two-dimensional set-up generating rapid granular flow owing to gravity. DEM simulations demonstrate that a rapid gas-like stream of grains suddenly decelerates across the shock wave and finally collapses into a slow-moving heap at the cylinder. The volume fraction suddenly increases across the shock layer and remains constant thereafter. The flow physics of the shock wave and the granular heap is elucidated through fundamental fluid dynamic quantities such as the velocity, volume fraction, pressure and granular temperature. It is shown that the interaction of grains with a cylindrical obstacle results in the generation of pressure, which is responsible for sustaining ...

Research paper thumbnail of Design and Analysis of Hand Gesture Controlled Quadcopter

2020 IEEE 23rd International Multitopic Conference (INMIC)

Hand control quadcopter, which is control of the motion of the hand. The user needs to wear a glo... more Hand control quadcopter, which is control of the motion of the hand. The user needs to wear a glove, which incorporates the sensors. The sensors will record the development of the movement in a particular direction, which will result in the development of the quad copter in that individual direction. The quad copter and hand motion glove are associated wirelessly by means of RF waves. The wireless correspondence empowers the user to cooperate with the quad copter in a friendlier manner. This project structured a quadcopter framework utilizing an ardupiolt mega2.8 chip with an RF transmitter with a few live control shapes accessible just as a mission organizer for autopilot control.

Research paper thumbnail of Rural Electrification through an Optimized Off-grid Microgrid based on Biogas, Solar, and Hydro Power

2020 International Conference on Engineering and Emerging Technologies (ICEET)

Renewable energy is the only solution to the problem of depleting environmental conditions and en... more Renewable energy is the only solution to the problem of depleting environmental conditions and energy shortage. Animal manure is a major output waste of rural areas and it can be converted into biogas through anaerobic digestion. Biogas is mainly CH4 which is combustible and can be used as fuel. In Pakistan, most of the rural population is relying on agriculture and cattle farming. Agriculture gives us hydro potential and cattle farming gives us biogas. And both of these resources, if used properly, can drastically improve the socioeconomic condition of rural areas. The sub-rural tehsil of Division Bahawalpur, “Mandi Yazman” is considered as a study area with the domestic load. This paper gives a techno-economic analysis of microgrid based on biogas, solar and hydropower to find out the best possible combination for lowest COE (cost of energy) and NPC (net present cost) according to the available resources in the proposed site.

Research paper thumbnail of Unit-19 Linkage in the Trade

Research paper thumbnail of Effect of Cross-Wire Tab Offset on Twin-Jet Mixing Characteristics

Proceedings of the 32nd International Symposium on Shock Waves (ISSW32 2019), 2019

Research paper thumbnail of Block-6 Development of travel and Tourism

Research paper thumbnail of Unit-5 Pilgrimage

Research paper thumbnail of Unit-20 Threats and Obstacles to Tourism

Research paper thumbnail of Unit-2 Understanding Tourism-II

Research paper thumbnail of Unit-3 Use of History

Research paper thumbnail of Parametric study and scaling of Mach 1.5 jet manipulation using steady fluidic injection

Physics of Fluids, 2022

We present the experimental investigation conducted to study the mixing characteristics of a Mach... more We present the experimental investigation conducted to study the mixing characteristics of a Mach 1.5 jet manipulation using steady fluidic injection. Two important parameters are investigated, namely, the number of injectors, N, and the mass flow rate ratio of the injector jet to the main jet, Cm, along with the expansion ratio of the main jet, [Formula: see text], where pe and pa are the nozzle exit and atmospheric pressures, respectively. The jet mixing quantified as a measure of supersonic core length, [Formula: see text], strongly depends on N, Cm, and [Formula: see text]. Two distinct regions behind the jet manipulation are identified, and a physical reasoning based on [Formula: see text] is presented using Pitot pressure measurements and Schlieren images. Empirical scaling analysis conducted on the experimental data for [Formula: see text] = f1( N, Cm, [Formula: see text], [Formula: see text]) is reduced to [Formula: see text] = [Formula: see text], where MRN is the momentum...

Research paper thumbnail of Performance Evaluation of Third Harmonic Injection PWM Technique for Three Phase Multilevel Inverter

2021 International Conference on Frontiers of Information Technology (FIT), 2021

Sensitivity of power system to various factors, such as voltage sags/swells and harmonics, has be... more Sensitivity of power system to various factors, such as voltage sags/swells and harmonics, has been increasing with rapid increase in automation. This study focuses on the reduction of harmonics of a three-phase Cascaded H-Bridge Multilevel Inverter (CHB-MLI) with Field Oriented Control (FOC) using the Third Harmonic Injection (THIPWM) technique. The aim is to increase the maximum utilization of DC bus along with the reduction of Total Harmonic Distortion (THD). The proposed design of MLI with THIPWM is compared with conventional techniques by taking THD into account for different types of loads. This research utilized MATLAB/Simulink as simulating, modelling and analyzing tool.

Research paper thumbnail of Detachment of strong shocks in confined granular flows

Journal of Fluid Mechanics, 2022

Granular flows are highly dissipative due to frictional resistance and inelasticity in collisions... more Granular flows are highly dissipative due to frictional resistance and inelasticity in collisions among grains. They are known to exhibit shock waves at velocities that are easily achieved in industrial and nature-driven flows such as avalanches and landslides. This experimental work investigates the formation of strong shock waves on triangular obstacles placed in a dry rapid granular stream in a confined two-dimensional set-up. Oblique attached shock waves are formed for mild turning angles and higher flow velocities, whereas strong bow shock waves are formed for higher turning angles and slower granular streams. A shadowgraph imaging technique elucidates interesting characteristics of the shock waves, especially in the vicinity of shock detachment. Velocity distributions in the form of scatter plots and probability distribution functions are calculated from the flow field data obtained by particle imaging velocimetry. The flow field around the granular shock wave region represent...

Research paper thumbnail of Optimized and Feasible Sustainable Energy System for Remotes Areas in Sindh by Utilizing HOMER

2020 IEEE 23rd International Multitopic Conference (INMIC), 2020

The utilization of sustainable power source is expanding everywhere throughout the world. This re... more The utilization of sustainable power source is expanding everywhere throughout the world. This research talked about the feasibility of giving power by utilizing hybrid sustainable power system to a far off small village, the populace of 15 families with a normal of five to six members in each family. The region of study, Kandhkot located in the Sindh, Pakistan. In the current scenarios, day by day vitality utilization of 500 kWh and a peak maximum load of 104 kW were taken into account. This research paper shows an approach to study different situations of sustainable power source system based on the economy, production of power, design, control, biomass accessibility and emissions of pollution. The HOMER programming software is utilized to completely simulate various situations. The output of this analysis demonstrates that the value of maximum capacity per year increases, the total present expense and levelized cost of vitality diminishes. The analysis of sensitivity parameters demonstrated that this design is the only optimized practical system under given varieties of various parameters.

Research paper thumbnail of A Study of State Feedback controllers for Pole Placement

2018 5th International Multi-Topic ICT Conference (IMTIC), 2018

A comprehensive study for pole placement of DC motor is studied using different state feedback co... more A comprehensive study for pole placement of DC motor is studied using different state feedback control techniques. It also compares the control parameters performance of the state feedback(SFB), feed-forward gain with state feedback(FFG-SFB) and integral control with State feedback controller(ICSFB). Ackermann’s formula being used for pole placement techniques. Performance level is based on the parameter of settling time, percentage overshoots and steady state error. The performance parameters are validated using Matlab/Simulink software.

Research paper thumbnail of An Optimized Off-gird Renewable AC/DC Microgrid for Remote Communities of Pakistan

2019 International Conference on Electrical, Communication, and Computer Engineering (ICECCE), 2019

Supplying electricity to rural areas can improve the socio-economic status of remote communities.... more Supplying electricity to rural areas can improve the socio-economic status of remote communities. Today, renewable energy technologies are the most focused research areas as they can play an important role in improving the quality of life by meeting the electricity demand. Indigenous renewable energy resources (RES) in these remote areas can be used to form a hybrid system that meets the electrical requirements of the community. This research explores a variety of hybrid and renewable energy systems (HRES) based on solar and wind resources to meet diverse community needs. The remote area of Pindiali (Latitude: 34 degrees 27.29 minutes North, Longitude 71 degrees 27.22 minutes East) in the Mohmand District of Pakistan is considered a study area. The system is designed and analyzed with anticipated load requirements and existing energy resources using HOMER software. The proposed system has a very low cost of energy (i.e., 0.166 $/kWh). The suggested solar wind hybrid system (SWHS) can be easily adapted to other areas of the globe with alike climates.

Research paper thumbnail of Soil stabilization using polypropylene

Submitted in partial fulfilment of the requirements for the degree of Bachelor of Civil Engineering

Research paper thumbnail of Interfacial Waves in Dual Stream Granular Flows

Research paper thumbnail of Experimental investigation of the effect of cross wire on the flow field of elliptic jet

International Journal of Heat and Fluid Flow, 2021

Abstract The effectiveness of cross wire in controlling the mixing characteristics of a circular ... more Abstract The effectiveness of cross wire in controlling the mixing characteristics of a circular and an equivalent elliptic jet is investigated experimentally. While circular jets are conventional, elliptic jets have gained attention due to their better mixing characteristics and faster decay. To further explore and augment the capabilities of elliptic jets for practical utility, it is investigated whether using an elliptic jet with cross wire control gives additional benefit in terms of mixing enhancement over an axisymmetric jet. Experiments are performed for subsonic and choked flow conditions with nozzle pressure ratios ranging from 1.2 to 7.0 . Time-averaged pitot pressures and schlieren visualization is used for diagnosis. The jet bifurcation can be seen in controlled elliptical jets at all nozzle pressure ratios (NPRs). Core length is reduced to as much as 70 % in the elliptical jet and 84 % in the case of the circular jet. The core length values estimated from the present data are compared with the previous investigations.