Research Experience

Doctoral Student, The University of Tokyo, Tokyo, Japan

October 2022 - Present

Argon propellant exhibits poor performance in comparison to xenon, due to the high thermal velocity attained by neutral argon atoms for a given gas temperature. As such, the neutral residence time of argon atoms is low in the ionization zone is low and neutral atoms escape the zone before bombarding an electron for ionization. This doctoral research aims to develop methodologies for control the velocity of argon atom for maximum propellant utilization efficiency, beginning with improving the effectiveness of the thruster cooling system by upgrading the design of the anode water cooling system to lower the equilibrium temperature of the thruster. Furthermore, new anode design through redesigning the gas injection system and the hollow anode shape is being implemented to reduce the neutral Ar propellant temperature.

Roles

• Experimental setup (Thrust stand, Faraday probe, plasma probes).

• Anode design implementation.

• Thruster operation from discharge power ranging from 500 W to 2.5 kW.

• DSMC using OpenFoam to evaluate neutral gas dynamic behavior.

Research Assistant, The University of Tokyo, Tokyo, Japan

October 2022 - September 2024

Conventional Hall thrusters use noble gases such as xenon and krypton, but scarcity of these noble gases prompts investigation into alternative propellants. Recent research explores solid propellants like CO2, iodine, and adamantane, supplied in gas the phase to the discharge channel. In this study, we propose a method of placing a solid propellant, specifically Polytetrafluoroethylene (PTFE), directly by making the channel walls out of PTFE, or inserting PTFE just in front of default channel walls. This research aims to understand the ablation of PTFE with the plume from a Hall thruster and verify any possible improvements in ion beam current (propellant utilization efficiency) due to ionization of ablated PTFE. 

Roles 

• Experimental setup (Thrust stand, Faraday probe, Collector plate, TEFLON injection system)

• Thruster operation at sub optimal condition for maximum plume divergence.

Research Assistant, The University of Tokyo, Tokyo, Japan

May 2021 - February 2022

Hall thruster have 2 major variants, Stationary Plasma Thruster (SPT) and  Thruster with Anode Layer (TAL). The channel wall is shorter in TAL, and is conducting unlike the SPT. To understand the physics of TAL, I tried modelling of the plasma in front of the conducting walls. This study was conducted using the HALL 1D PIC (Particle in Cell) code developed by Prof. Rei Kawashima.

Roles

• Extension of HALL 1D FORTRAN code 

Made the code suitable for RAIJIN-66 Hall thruster (original code made for SPT variant)

• FORTRAN code compatible with argon as propellant (originally only worked for Xe)

Master's student, The University of Tokyo, Tokyo, Japan

October 2020 - September 2022

Theoretically, the thermal velocity of neutral gas atom increases as the temperature of the gas increases. For a Hall thruster at any given power, until the steady state condition is reached, performance continues to decrease with increase in thermal velocity, which leads to poor ionization as a result of low neutral residence time. To evaluate this experimentally, a thermal drift free thrust stand capable of real time thrust measurement (during transient operation) was developed and the thrust was measured from the beginning of the experiment, as opposed to other thrust measurements which are conducted only after steady state condition is achieved. The exponential decay in performance with gas temperature was confirmed with this study.

Roles

• Development of temperature uniform plates for thermal-drift free thrust measurement.

• Clarification of exponential decay of thrust performance.

Project Assistant, KIIT University, Bhubaneswar, India, 

July 2019 - January 2020

Mechanical and electrical designs for a micro-pulsed plasma thruster were done, which was planned to be accommodated in the KIIT University’s Nanosatellite for technological demonstration in space. Design-related calculations based on dimensional limitations of the nanosatellite, power constraints, and optimal thruster performance were done. Mechanical design included accurate computer-aided design (CAD) and physical calculations of thruster casing, miniature spark plug, and electrodes. The electrical design included the printed circuit board (PCB) design and circuit-related calculations. Analysis of both the mechanical and electrical system were done using SOLIDWORKS and PROTEUS software, respectively, for critical validation. 

Roles

• Design and FEM analysis of the Micro Pulsed Plasma Thruster.

• Evaluation of the electrical system for this Micro-PPT.

• Critical analysis of compatibility of Micro-PPT with KIIT Nanosatellite.

Research Intern, Institute of Plasma Research, Ahmedabad, India

May 2018 - July 2018

The research study reported the design of vertical vacuum chamber for basic plasma physics experiments at a pressure if 1E-6 mbar. Design of a vertical cylindrical vacuum chamber having outer diameter 50 cm and height 60 cm with eight number of diagnostic ports was done. ASME BPV code Section VIII division 1, was used for design of a vacuum chamber under external atmospheric pressure along with the mathematical calculations for thickness, end plates and ports. Finite element analysis of the vertical vacuum chamber was carried as well as validate with ASME standard. The selection of cost effective vacuum pump was done by pump down time along with conductance calculations for viscous and molecular flow.

Roles

• Chamber, flange, nozzle and window thickness calculations.

• Pump calculations for cost effectiveness.

• FEM structural analysis

Research Intern, Tokyo University of Agriculture and Technology, Tokyo, Japan

May 2017 - July 2017

This study involved experimentally characterizing the Helicon Plasma Thruster with Rotating Magnetic Field coils and m=0 coils for plasma acceleration. Although the thrust to power ratio was significantly low compared to more conventional ion thrusters, the no erosion in this thruster basically makes it a limitless thruster as long as there is propellant supply. My work involved use of emissive probes for plasma characterization and DSMC simulation to evaluate the neutral gas behavior.

Roles

• Plasma characterization with emissive probes

• Neutral gas behavior evaluation using DSMC (MOLFLOW).