PROJECTS IN RECENT PAST

1. Biomass derived aviation fuel (four different pathways of production)

The rising environmental issues result in more stringent aviation policies. There are restrictions set on emissions from the aviation sector for the future, and it is therefore imperative to implement alternative jet fuels with lesser human and environmental health impacts. Several blends of bio-jet fuels from various fuel feedstocks and pathways, have been approved as drop-in fuels by regulatory agencies. This project examines four different pathways of bio-jet fuel production, based on their human and environmental health performance. This quantitative assessment is conducted by using a Life Cycle Assessment (LCA) tool. Such quantitative studies evaluate all bio-jet fuel types based on their performance with respect to greenhouse gas emissions, criteria air pollutants, fossil fuel usage and water consumption, and this might help in the selection process of a production pathway/feedstock with the potential to positively impact human and environmental health. This might further enable the investment process in the correct technology/infrastructure towards sustainable production. Projects like these can potentially drive decision makers and researchers in technology development, and policy makers, in making more informed decisions. The following short video by Boeing educates us about the need of bio-jet fuels, its production and lastly its environmental impact.

This project so far has four publications, one each on four different pathways of bio-jet fuel production. These four pathways and respective publications are as follows:

Hydroprocessed Esters and Fatty Acids (HEFA) Synthetic Paraffin Kerosene (SPK):
A paper titled "Sustainability assessment of hydro-processed renewable jet fuel from algae from market-entry year 2020: Use in passenger aircrafts" was published in 16th American Institute of Aeronautics and Astronautics - Aviation Technology, Integration, and Operations Conference, Washington D.C. This paper explores the life-cycle performance of algae as a feedstock to produce HEFA bio-jet fuel (neat/100%). This paper can be read from here. For this paper, I received two travel grants from Georgia Institute of Technology. The first travel grant from the Dean of College of Engineering and second from Student Government Association, at Georgia Institute of Technology.
Alcohol-to-jet fuel (ATJ) SPK:
A paper titled "Assessment of feedstocks for blended alcohol-to-jet fuel manufacturing from standalone and distributed scheme for sustainable aviation" was published in AIAA Propulsion and Energy 2019 Forum, Indianapolis. This paper explores the life-cycle performance of 18 different feedstock+manufacturing plant types to produce 30% blended ATJ-SPK (approved drop-in fuel). This paper can be read from here.
Sugar-to-jet fuel (STJ) SPK:
A paper titled "Comparative assessment of manufacturing setups for blended sugar-to-aviation fuel production from non-food feedstocks for green aviation" was published in AIAA Propulsion and Energy 2019 Forum, Indianapolis. This paper explores the life-cycle performance of 24 different feedstock+manufacturing plant types to produce 10% blended STJ-SPK (approved drop-in fuel). This paper can be read from here.
Fischer-Tropsch (FT) SPK:
A paper titled "Evaluation of blended Fischer-Tropsch jet fuel feedstocks for minimizing human and environmental health impacts of aviation" was published in AIAA Propulsion and Energy 2019 Forum, Indianapolis. This paper explores the life-cycle performance of 7 different feedstocks to produce 50% blended FT-SPK (approved drop-in fuel). This paper can be read from here.

2. Evaluation of future Hybrid-electric aircraft propulsion concepts using Systems Engineering approach

In this project, an assessment of subsonic aircraft concepts with hybrid-electric propulsion (for 300 passengers) towards NASA N+3 goals (i.e. expected to enter market after year 2035) is conducted at systems-level. Systems engineering methods are used for the evaluation and therefore the selection of the best concept, from Boeing SUGAR (Subsonic Ultra Green Aircraft Research) Volt, NASA N3-X TeDP (Turboelectric Distributed Propulsion), MIT Double-bubble, and Northrop Grumman SELECT (Silent Efficient Low-Emissions Commercial Transport). The ‘Georgia Tech Integrated Product-Process Development (IPPD)’ procedure is used in this project for conceptualizing a civil aircraft that meets the N+3 goals. A study of this nature is helpful in the first phase of any project. It enables any modifications to be made to the designs in the early stages of the project. Moreover, such studies are helpful in reducing life-cycle costs. The mentioned study estimates that the NASA N3-X TeDP concept will provide greater environmental advantage, of the four design-concepts considered. A Journal article is accepted for publication and is 'In-Press' in the International Journal of Automotive and Mechanical Engineering.

Boeing SUGAR VOLT

Source: https://alchetron.com/SUGAR-Volt

Northrop Grumman SELECT

Source: https://tinyurl.com/y2q5zr6h

NASA N3X TeDP

Source: https://www1.grc.nasa.gov/aeronautics/hep/

MIT Double Bubble

Source: https://tinyurl.com/y3jrv5gx

PROJECTS UNDERTAKEN IN MASTER OF SCIENCE STUDIES

1. MS degree research problem (at Georgia Institute of Technology)

The research problem was titled 'Spatio-temporal linear stability analysis of stratified planar wakes: Velocity and density asymmetry effects'. We were exploring the effects of variable density and velocity in a bluff-body flow. The applications of this research is to NextGen aircraft combustors, for enabling cleaner combustion without any hydrodynamic instabilities. This will improve the safety of engines/aircrafts. This research involved processing experimental data and also developing computational model and validation of results. The two images below show a bluff body flow. The image on the left side below is the 'proper orthogonal decomposition' and on right side is the 'dynamic mode decomposition' of the experimental data used towards the analysis. This research was published in Physics of Fluids journal, SciTech 2015 conference of American Institute of Aeronautics and Astronautics, and US National Energy Technology Laboratory, Department of Energy (with respective links to publication).

10386369_1548565738730719_60802157593004

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2. Patent on 'Heat recuperation system for the family of shaft powered aircraft gas turbine engines'

Heat recuperation system for the family of shaft powered aircraft gas turbine engines, comprise of a shaft powered gas turbine engine, where the engine has an Annular Shaped Heat Exchanger with Finned-Tubes (ASHEFT) located in the exhaust system and a heat recovery apparatus functionally coupled to the ASHEFT. The design of ASHEFT is innovative considering its application in the annular space. The ASHEFT with working fluid recovers heat from the exhaust gas. The recovered heat vaporizes the working fluid which drives a turbo-expander. The mechanical work developed by the turbo-expander can be used for driving the propulsion systems, compressor or an electric generator. The thermal energy available after expansion work can be used to heat the inlet air into the engine to prevent ice ingestion during icing conditions. This system increases performance and life of the engine, and reduces emissions, heat released to the environment, fuel consumption and fuel cost. It has applications to future aircraft concepts like NASA N3X Turbo-electric Distributed Propulsion (TeDP), which is a hybrid-electric aircraft concept for entry-in-service after year 2035. This patent has been granted by the United States Patent and Trademark Office in July 2019 (priority/application date 29 October 2014), and is currently pending with Indian Patent office (with respective links to publication). The PCT (International Bureau) patent application can be found here. This project was completely crow-funded (raised around US $1000), and the patent was self-drafted. The patent issuing process was completed as pro-se legal proceeding towards the grant of the patent by the United States Patent and Trademark Office.

NASA N3X TeDP

Source: https://www1.grc.nasa.gov/aeronautics/hep/

3. Aero-thermodynamic analysis of a space shuttle vehicle at re-entry

Since the last two decades, aerospace agencies around the world have started planning Space-based Solar Power Systems (SSPS) as an alternative power source. The use of Space Shuttle Orbiter type re-usable launch vehicles will enable the completion of this project in a limited time span with economic feasibility. This would leave less time between successive launches, making it imperative that the aero-thermodynamic analysis of these vehicles be fast and accurate. Currently, aero-thermodynamic analysis is done by high fidelity Computational Fluid Dynamics (CFD) solvers which are accurate but take significantly more time to give necessary results. Therefore, the present CFD solvers might not be useful tools for this mission to be completed in limited time. In this project a low cost, quick and reasonably accurate model is developed when compared with the CFD results. Pressure coefficients and surface temperatures from this code are compared with results from the CFD solver of `Air Force Research Lab, Wright-Patterson'. The model developed in this project is based on hypersonic theories, which meet the requirements of this mission. The surface temperature estimation method developed in this project is called as 'streamline walking and panel number inclination logic'. A peer-reviewed paper titled "aero-thermodynamic analysis of space shuttle vehicle at re-entry" was presented and published at International IEEE Aerospace Conference 2015, and I received Leon A. Tolve fellowship for this research from Georgia Institute of Technology. The link to this paper can be found here. The image below shows the temperature distribution over space shuttle at re-entry condition at Mach 18 and angle of attack 40 degrees, and atmospheric condition at 241 K and pressure of 13.7 Pa

PROJECTS UNDERTAKEN IN UNDER-GRADUATE STUDIES

1. ‘Solar Refrigeration’ - (B.E. Project) (2011-2012)

The main objective was to provide cold storage in desert or remote areas where 24x7 electricity is not available & the use of an alternative source of energy for the most important process called ‘Refrigeration’ in any industry or domestic application. This system can be used to store fishes on the ship itself rather than catching the fish, then coming back to the port & storing it. This delay causes attack of bacteria on the fish. Furthermore, it can be used in medical field for storage of vaccines & blood. It also has agricultural application like storing seeds & fertilizers. This paper can be found here.

Various possible methods for Solar Refrigeration were studied. These included

i) A Vapor Compression Refrigerator (VCR) to be powered by solar photovoltaic cells.

ii) Harnessing solar thermal energy by means of a thermal collector (all types of thermal collectors

were studied like the flat plate collector, compound parabolic collector, Solar Parabolic Trough

(SPT), parabolid dish collector) which would power a Sterling Engine. The sterling Engine would

then be coupled to the compressor of VCR. (The efficient & cost effective of all the thermal

collectors was a SPT & thus was selected as our thermal collector).

iii) Desiccant Cooling systems.

iv) Vapor Absorption Refrigeration systems (VARs) using two fluids coupled to a SPT.

v) Triple Fluid Vapor Absorption Refrigeration system (TFVARs) coupled to a SPT, since it had no

reciprocating parts i.e was maintenance-free & noiseless & thus had possible applications in

Hospitals & schools/colleges.

vi) Organic Rankine Cycle (ORC): Turbine of ORC will be coupled to the compressor of VCR. The thermal

Energy required for the process will be provided by SPT.

The efficient of the above was the TFVARS as it was noiseless & economical. For large scale application TFVARS system & ORC are the possible solution. The fabricated system: Receiver of the SPT uses air as a thermic fluid. The SPT was with a profile of parabola having equation X^2=80Y, area = 1 sq.m (aperture= 0.5 m & length= 1 m) & concentration ration of 9.047 & was coupled to a 41 liter TFVARS. We fabricated the SPT at a much cheaper cost at about $137 which conventionally cost about $365 of the same configuration.

2. ANSYS project for the subject of Finite Element Analysis (Open Choice)

Analysis of the iron supports of the fabricated SPT was done for vertical load.
Also the thermal analysis of the receiver tube of SPT was done.
CATIA project (Open Choice): (September 2011)
Modeled & analysed the design of the structure of fabricated SPT.

3. Database Management system project using SQL & Visual Basics

Mark-sheet generating code for a University/college where one can enter the seat number of a candidate & see details like name, seat number & marks. Also there was a provision made for an authority with login service so that changes can be made to the database if required.
On the same grounds an Admission Process program was developed which included details like name, gender, date of birth, marks of the candidate.

Testing with the fabricated Solar Parabolic Trough with Profile X^2=80Y

(Without stands, manual tracking & Zero mass flow rate of air). Maximum Temperature reached was 155 degree C.

Manufactured Solar Parabolic Trough X^2 = 80Y, Area 1 sq. m, length 2m & width 0.5m. Receiver Diameter 19mm, enveloped by acrylic tube to prevent heat losses to the surrounding, Iron stands & automatic tracking with the trough to be reset once in the evening manually.

PROJECTS IN RECENT PAST

1. Biomass derived aviation fuel (four different pathways of production)

​

This project so far has four publications, one each on four different pathways of bio-jet fuel production. These four pathways and respective publications are as follows:

​

2. Evaluation of future Hybrid-electric aircraft propulsion concepts using Systems Engineering approach

​

Boeing SUGAR VOLT

Source: https://alchetron.com/SUGAR-Volt

Northrop Grumman SELECT

Source: https://tinyurl.com/y2q5zr6h

NASA N3X TeDP

Source: https://www1.grc.nasa.gov/aeronautics/hep/

MIT Double Bubble

Source: https://tinyurl.com/y3jrv5gx

PROJECTS UNDERTAKEN IN MASTER OF SCIENCE STUDIES

﻿

1. MS degree research problem (at Georgia Institute of Technology)

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2. Patent on 'Heat recuperation system for the family of shaft powered aircraft gas turbine engines'

​

NASA N3X TeDP

Source: https://www1.grc.nasa.gov/aeronautics/hep/

3. Aero-thermodynamic analysis of a space shuttle vehicle at re-entry

​

PROJECTS UNDERTAKEN IN UNDER-GRADUATE STUDIES

﻿

1. ‘Solar Refrigeration’ - (B.E. Project) (2011-2012)

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Various possible methods for Solar Refrigeration were studied. These included​

i) A Vapor Compression Refrigerator (VCR) to be powered by solar photovoltaic cells.​

﻿ ii) Harnessing solar thermal energy by means of a thermal collector (all types of thermal collectors

were studied like the flat plate collector, compound parabolic collector, Solar Parabolic Trough

(SPT), parabolid dish collector) which would power a Sterling Engine. The sterling Engine would

then be coupled to the compressor of VCR. (The efficient & cost effective of all the thermal

collectors was a SPT & thus was selected as our thermal collector).​

﻿ iii) Desiccant Cooling systems.​

﻿ iv) Vapor Absorption Refrigeration systems (VARs) using two fluids coupled to a SPT.​

﻿ v) Triple Fluid Vapor Absorption Refrigeration system (TFVARs) coupled to a SPT, since it had no

reciprocating parts i.e was maintenance-free & noiseless & thus had possible applications in

Hospitals & schools/colleges.​

﻿ vi) Organic Rankine Cycle (ORC): Turbine of ORC will be coupled to the compressor of VCR. The thermal

Energy required for the process will be provided by SPT.​ ​

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Various possible methods for Solar Refrigeration were studied. These included

i) A Vapor Compression Refrigerator (VCR) to be powered by solar photovoltaic cells.

ii) Harnessing solar thermal energy by means of a thermal collector (all types of thermal collectors

collectors was a SPT & thus was selected as our thermal collector).

iii) Desiccant Cooling systems.

iv) Vapor Absorption Refrigeration systems (VARs) using two fluids coupled to a SPT.

v) Triple Fluid Vapor Absorption Refrigeration system (TFVARs) coupled to a SPT, since it had no

Hospitals & schools/colleges.

vi) Organic Rankine Cycle (ORC): Turbine of ORC will be coupled to the compressor of VCR. The thermal

Energy required for the process will be provided by SPT.

Analysis of the iron supports of the fabricated SPT was done for vertical load.

Also the thermal analysis of the receiver tube of SPT was done.

CATIA project (Open Choice): (September 2011)

Modeled & analysed the design of the structure of fabricated SPT.

Mark-sheet generating code for a University/college where one can enter the seat number of a candidate & see details like name, seat number & marks. Also there was a provision made for an authority with login service so that changes can be made to the database if required.