George W. Woodruff School of Mechanical Engineering

Georgia Institute of Technology Atlanta, GA

Atomistic Simulation & Energy (ASE) Research Group

Graduate Research Assistant 

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(I) Concentrated Solar Power (CSP) and Solid State Energy Conversion Systems (Sponsored by DOE)

Designed and analyzed a novel solid state energy conversion heat engine for solar thermal applications

  • Contributed to the design of a high temperature (1350°C) solar receiver for CSP with liquid metal as heat transfer fluid 
  • Designed and modeled a high temperature thermophotovoltaic (TPV) system for concentrated solar power (CSP) with thermal energy storage (TES).

In press

.(II) Lattice Thermal Conductivity of Random Semiconductor Alloys (Sponsored by NSF)

Explained the reason for failure of Phonon Gas Model (PGM) and Virtual Crystal Approximation (VCA) for thermal conductivity of alloys that have been used over the last 50 years. Also discovered that the presence of impurity in crystalline materials even in dilute regime fundamentally changes the character of the modes of vibrations.

  • Calculated the thermal conductivity of InGaAs thin films with excellent agreement with experiments.
  • Performed lattice dynamics calculations on InGaP, InGaSb, AlAsSb, AlGaAsSb random alloys.
  • Collaborated with experimentalists to measure thermal conductivity of InGaAs and AlGaN alloys using Time Domain Thermoreflectance (TDTR).

(III) Phonon Transport in Amorphous Solids (Sponsored by Intel and NSF)

Utilized molecular dynamics simulation to understand heat conduction in amorphous materials

  • Developed a new computational approach to identify the propagating vibrational modes in disordered solids for the first time.
  • Studied the importance of negative phase quotient non-propagating modes (diffusons and locons) in amorphous solids (a-SiO2 and a-C) and InGaAs random alloys.
  • Calculated thermal conductivity of amorphous carbon using Green Kubo Modal Analysis (GKMA).

(IV) Empirical Potential Development

Utilized Density Functional Theory (DFT) and Genetic Algorithm to develop empirical interatomic potentials (EIPs) for molecular dynamics simulations.

  • Used Genetic Algorithm (GA) to develop interatomic potential for crystalline solids and random alloys using DFT inputs.
  • Calculated structural and thermal properties of various crystalline materials (Si, Ge, GaN, AlN, InAs, GaAs, etc) using both DFT and EIP.

University of Missouri- Columbia

School Mechanical and Aerospace Engineering, Missouri, Columbia

Multiscale Thermal Transport Laboratory (MTTL)

Graduate Research Assistant

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(I) Electronics Cooling & Thermal Management (Sponsored by NSF)    

Proposed different strategies to enhance the thermal performance of various liquid/air-cooled heat sinks

  • Proposed a metal foam air-cooled heat sinks that enhances cooling performance over 400%
  • Designed a novel octadecane-polyalphaolefin(PAO)-cooled microtube heat sink with tangential impingement
  • Optimized microchannel heat exchangers with Al2O3/CuO nanofluid coolants using entropy generation minimization approach
  • Analyzed the thermal performance of tangential microchannel heat sinks and proposed improvements to cooling efficiency 

(II) Boiling Heat Transfer and Phase Change Materials (Sponsored by NSF)  

Conducted fundamental study on phase change heat transfer using atomistic and macro-scale models

  • Developed a molecular dynamics simulation model for normal and explosive boiling over various nanostructured surfaces
  • Performed two-dimensional VOF numerical simulation of nucleate boiling
  • Conducted fundamental study on the effect of phase change slurry on heat transfer enhancement
  • Developed a numerical model to analyze thermal performance of pulsating heat pipes

Karaj Azad University

School Mechanical Engineering,  Alborz, Iran

Research Assistant

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Heat Pipes, Microchannels, Air Cooled Thermal Management, and Turbine Blade Cooling

Studied the thermal and hydrodynamics performance of various heat pipes and microchannels

  • Obtained 2D analytical solution of full Navier-Stokes and energy equations  in parallel plate and circular microchannels
  • Proposed accurate 2D closed form analytical models to predict vapor/liquid flows in flat plate heat pipes for the first time
  • Developed simplified models to predict capillary limit in circular/annular heat pipes with great agreement with the CFD
  • Developed a 3D CFD model to study film cooling on a turbine rotor blade.
  • Conducted optimization study on various liquid-cooled microchannel pin fin heat sinks with different pin geometries
  • Conducted CFD simulations to study thermal and hydrodynamic performance of elliptic pin fin heat sinks with and without metal foam insert.
  • Numerically analyzed the thermal and hydrodynamics performance of metal foam heat sinks under forced and natural convection.