Projects Portfolio

PROJECTS PORTFOLIO

Computer Aided Designing

‘Developed an Aerodynamic Design for a Solar Powered Car’ The project was accomplished individually over a period of 8 months as an undergraduate research project.

Conceptualized, Optimized, Modelled, Designed and Validated an outline design for a solar powered commuter car.

Generated several initial concepts by employing hand sketching & brainstorming techniques

Modelled the shortlisted concepts in a 3d CAD software (Autodesk Inventor) as shown below

Selected the final design for overall body shape using a Decision Matrix with following as decisive criterion –

Energy Requirements, Solar Cell Area to Car Weight Ratio, Manufacturability, Safety & Stability, and Drag Coefficient.

Researched alternative methods of minimizing energy requirements (low rolling resistance tyres, minimising weight, etc.).

Authored a technical report to justify the workability, manufacturability and economic feasibility of the final car design.

Computational Fluid Dynamics / Finite Element Analysis

‘Simulated and thus analysed the three-dimensional boundary layer airflow over a wing’ Investigated flow over the wing of Lockheed 1049 Constellation under the influence of a range of Mach Numbers

The geometry of wing was modelled using CREO (ProEngineer) while CFD simulation was accomplished using ANSYS CFX. The CAD model as well as meshed domain for final problem geometry are shown below on Left Hand Side.

Lift and Drag forces were also recorded for each of the solutions. Lift produced on the wing constantly increased with increase in velocity. The behaviour of Drag Coefficient very closely matched that of experimental results as shown above on Right Hand Side.

As a qualitative analysis, the accuracy of simulated flow was investigated (i.e., the accurateness of the simulation in modelling incompressible flow for low velocities and compressible flow for high velocities), by analysing Density Contour Plots obtained using CFX-Post. The figures on Left Hand Side summarize this analysis.

Simulation results were then used to quantify the changes in flow behaviour as it transitions from incompressible to compressible regime due to increase in Mach number which results in an increase in compressibility of the fluid.

Challenges

Computer Aided Designing : 3-d Modelling of wing was a challenging and time consuming task as it consisted of different Root & Tip Airfoils).

Domain Size : Choosing the right domain size was difficult. For a flow at steady state, the pressure at all boundaries must be equal, as boundaries are assumed to be located at infinity. This would require an infinitely big domain, thus it’s preferred to have a domain as big as possible. But, bigger domains mean a bigger mesh, which in turn require more computer power. So, a compromise has to be made.

‘Analysed External Boundary Layer Flow over a Turbine Blade’The intention of this project work is to familiarize oneself with basic computational analysis of flow over a gas turbine blade. Main objectives were:

To simulate external flow over a turbine blade with a view to resolve the buffer layer region of the turbulent boundary layer using CFD resources such as CFX and TurboGrid.

To study the effects of an increasing turbulent intensity on various boundary layer characteristics (such as turbulence kinetic energy).

Figures above show the 3-d view of the model with all 67 blades, the span wise view of a single blade and the meshed domain respectively.

BladeGen was used to generate the blade model and TurboGrid was used for meshing the domain while CFD Software - CFX – was used to simulate the flow. The model was chosen to be the nozzle blade row of first stage of a low-pressure power turbine which was designed for another turbo machinery project.

Computational techniques (such as law of the wall/log law) was used to accurately capture turbulent boundary layer over turbine blades.

The changes in boundary layer characteristics (such as turbulence kinetic energy) with simultaneous changes in inlet flow conditions i.e., turbulence intensity at inlet were studied and quantified.

Effect of Increasing Turbulence Intensity on Turbulence KE can be seen in adjacent figures. Evidently, as turbulence intensity increases, turbulent velocity fluctuations become more and more dominant near the leading edge & mid-chord region of blade which results in a higher Turbulence KE in these regions.

Numerical Analysis/ Turbomachinery Design

‘Performed a Preliminary Aerodynamic Design of Axial Turbine for an Industrial Gas Turbine Engine’

A successful design for required power turbine had to satisfy the requirement of inlet total pressure & temperature (605 kPa & 1048 K) as well as engine specifications given in the table below, which were predefined.

Established basic parameters (number of stages, desirable power output per stage, number of blades per blade row, annulus geometry, etc.) by initial hand calculations and a detailed numerical analysis in MS Excel. Calculated mean line as well as root and tip flow through the turbine using

a computer code (called ‘GTE-TMLD’, initially developed for Rolls-Royce Gas Turbine Engines Ltd by Carleton University).

Carried out optimization study for Stage 1 with a view to improve the stage efficiency (improved from 0.865 to 0.88).

The final design consisted of a 5 - Stage Turbine with stage efficiencies ranging from 0.88 - 0.905

Developed a scale drawing of the overall final design (in Section View) using MS Visio & MS Excel as seen on the Left Hand Side.

Hand calculations were carried out in MS Excel by employing the meanline analysis approach which treats flow as one-dimensional and calculates basic parameters at

the mean radius→rm2=(rh

2+rt2)/2. The hand calculation results were only used as input data for TMLD, hence TMLD was explicitly used to fine-tune the first

estimate of design.

‘Performed a Preliminary Thermodynamic Design of a Turbofan Engine for a medium range airliner’

The cruise Thrust, Mach number, altitude and the fan diameter are all fixed. Moreover, the fan pressure ratio (FPR) and turbine inlet temperature (TIT) are already chosen. The engine is to use a 3-spool configuration. The cooling bleed for HP & LP turbine along with the pressure loss during combustion is specified. The efficiencies of nozzles, shafts and turbo-machinery are also given. The optimum OPR and BPR is to be obtained for this engine.

The intention of this project work was to familiarize with basic thermodynamic design of a turbofan engine for a medium range airliner (about 6000 miles). During the thermodynamic design of a turbofan, the primary goal is to obtain optimum values for the four thermodynamic parameters ‘Overall Pressure Ratio’ ‘Turbine Inlet Temperature’ ‘Fan Pressure Ratio’ ‘Bypass Ratio’, however, two of these parameters - the Turbine Inlet Temperature and the Fan Pressure Ratio were already chosen.

The Overall Pressure Ratio (OPR) and Bypass Ratio (BPR) were optimized with a view to utilize the most efficient thermodynamic cycle that may exist for the required turbofan engine at given design conditions.

The design process was iterative and detailed calculations had to be carried out over a range of OPR & BPR while keeping the FPR & TIT fixed. The numerical analysis for purpose of this project work was accomplished using MS Excel.

The following table lists key results for final chosen turbofan design, which respects the given constraints on Mass Flow, FPR, TIT and efficiencies.

Radii

Axial Length

Shaft Power Output

Mass Flow Rate

Rotational Speed

Inlet Mean Radius

Inlet Flow Area

60 MW 155 Kg/s 3600 RPM 0.5 m 0.45 sq. m

BPR OPR Thrust SFC Mass Flow Rate CNc CNh

4.8 24 0.07416 kg/hr.N 368.53 kg/s 305.329 m/s 557.915 m/s

Other Projects Undertaken

Numerical Analysis

o ‘Utilized results of potential flow theory for predicting flow separation angle using the Thwaites’ Integral Method’

o ‘Numerically analysed the supersonic and subsonic flow in a convergent-divergent nozzle using 3 different numerical solvers in MATLAB’

Lightweight Structure Design/Finite Element Analysis

o ‘Numerically analysed the supersonic and subsonic flow in a convergent-divergent nozzle using 3 different numerical solvers in MATLAB’

o ‘Designed and Optimized a Box Beam (wing box) for a Cantilever Loading Case’

o ‘Designed and Built a motor mount to fit onto a square tube shaped pylon of a glider’

o ‘Reverse Engineered an All-Terrain Crane for accomplishing an assignment on design of Lightweight Structures.’ For this assignment, Autodesk AutoCAD was used to present the findings.

Research and Benchmarking

o ‘Researched, Benchmarked and Reported the history, current technologies, applications and future trends for various types of Material Handling Equipment and Systems.’

Computational Welding Analysis

o ‘Computational Welding Analysis of a Panel Top with 4 Weld Passes using VrWeld Suite.’