Prithwish Kundu

In this role I lead the Battery and Thermal teams for the development of batteries for cargo electric vehicles. The main responsibilities include: Research and Development of liquid cooled battery pack designs for different payload categories Developing designs and manufacturing strategies for localization and supply chain optimization of battery components Active cooling systems (BCS) development, optimization and validation at high temperature operating conditions Investigation of Li-ion cell chemistries and cell ageing characteristics Development of advanced cooling strategies coupled with pulse charging Development of ultra-fast charging capabilities Liquid cooling channel and cold plate design for different battery packs Development of immersion cooled battery packs

Hypersonic Air-Breathing Propulsion - NASA Langley and US Air Force • Got funded by NASA Langley Research Center for starting key research projects in hypersonics related to integration of deep neural networks with hypersonic propulsion. Worked with NASA to implement combustion models into their in-house VULCAN CFD code for hypersonic applications. • Led the development of flamelet model implementation into NASA’s VULCAN code for scramjets. Modeled scramjet combustion including the HiFIRE 2 datasets and also carried out scalability studies. • Worked in collaboration with US AFRL to carry out LES calculations for methane-oxygen rocket RDEs. Demonstrated model validation against experimental data. Gas Turbine Combustion • Established gas turbine combustion modeling research activities in the lab as a Principal Investigator (PI) and extensively contributed to the National Jet Fuels Combustion Program (NJFCP). Modeled reacting spray flames in realistic combustors and investigated lean blowout (LBO) for traditional and bio-derived alternative jet fuels using reacting flow, LES calculations with detailed chemical kinetics. Efforts led to scientific publications and an AIAA book co-authorship. • Worked closely with NASA Glenn Research Center, FAA, AFRL and industry partners, viz. GE, UTRC, Rolls-Royce, Honeywell under the NJFCP collaboration. • Established and led a project in collaboration with the US Army to develop models for LBO in gas turbines. Collaborated with Argonne X-ray beamline scientists to obtain, first of its kind, near nozzle droplet diameters for initializing Lagrangian sprays in LES calculations. Patent with Caterpillar Inc. • Led project with Caterpillar to optimize heat transfer in engines using CFD simulations and supercomputers • Project led to a joint patent with Caterpillar : Internal combustion engine and piston having stepped combustion bowl with non-axisymmetric profile

Turbulent combustion research on cool flames and code development Carried out extensive research in the field of turbulence chemistry interactions (TCI) and their coupled effects with complex chemical kinetics, for hydrocarbons, in negative temperature coefficient (NTC) regimes Developed in-house codes based on novel chemistry tabulation of multidimensional flamelet manifolds. Developed parallel codes and coupled these reacting flow models for URANS and LES calculations in the CONVERGE CFD source code. Led the development of an unsteady flamelet code - “Argonne Flamelet Solver”, capable of handling chemistry mechanisms with 3000+ species in a parallel MPI framework. Successfully demonstrated its coupling of high fidelity flamelet based manifolds with URANS and LES modules in the CONVERGE code. Demonstrated and validated the largest LES calculation in literature, with respect to chemical kinetics mechanism, using the Argonne Flamelet Solver for an n-dodecane spray flame. Led a collaboration with Lawrence Livermore National Laboratory and US Army Research Laboratory to develop computational models and kinetic mechanisms that can accomodate the latest multi-component fuel surrogates. Spray flame validation results demonstrated the very first use of such highly detailed fuel surrogates with 1544 species in a LES framework. Mentored a PhD student in developing and implementing a two-equation soot model, where, soot equations are solved within the flamelet domain.

Combustion model development for non premixed turbulent flames: •Developed a new combustion model for non-premixed combustion based on multiple flamelet theory and tabulated chemistry. •Implemented combustion model in CONVERGE CFD code. Validated model against diesel spray injection experimental data (Sandia Spray A). •Demonstrated significant speed up with tabulation. •Developed parallel codes in C using Message Passing Interface (MPI) to generate multidimensional tabulated chemistry database for CFD combustion modeling using a 1D flamelet equation solver. Implemented efficient multiple variable interpolation schemes in CFD code for multi-dimensional look-up tables.

Combustion modeling of diesel sprays and diesel engines: • RANS and Large Eddy Simulations of diesel spray (Sandia ECN Spray A) combustion modeling with Representative Interactive Flamelet (RIF) model in CONVERGE CFD code. • Comparative study of simulation results from different combustion models, turbulence models across a wide range of operating conditions and validation of CFD model against experimental data. • Evaluation of turbulence chemistry interactions in diffusion flames for diesel engine conditions using RIF model. • Simulation of Caterpillar 3410E single cylinder diesel engine with different diesel surrogates using R.I.F. model. • Carried out comparative study of effect of different reaction mechanisms, combustion models and multiple flamelet initialization strategies with RIF on diesel engines and validation of model against experimental results. • Contributed data to Engine Combustion Network’s 3rd workshop proceedings.

The PhD thesis was focused on high-pressure spray flames. It investigated the fundamental nature and impact of strain rate history effects on high pressure flames. Multidimensional manifolds were developed to represent complex chemical kinetics. An equivalent strain rate model was developed to account for strain rate effects in multidimensional manifolds (flamelet models). This phenomenon is observed in almost all propulsion devices like jet/aero engines, diesel engines, rocket engines, etc. It also involved developing high fidelity tabulated reactive flow models and manifold generator codes in a parallel architecture. These codes were then coupled with a reacting flow CFD solver. The models were validated on high performance computing facilities at Argonne National Laboratory. This work was in close collaboration with the same institution. It led to the publication of multiple scientific journal papers and software copyrights.

Thesis: “Gas Turbine Combustion Chamber Design for Viscous Fuels” Conducted research in the area of viscous fuel combustion for gas turbines. It involved research and development of gas turbine combustion chambers capable of burning high viscosity fuels. It involved retrofitting an existing combustion chamber design with necessary modifications. A computational model was developed in Ansys CFX accounting for the spray combustion and NOx formation of viscous fuels. These models were used for combustion chamber optimization and final fabrication. Special optimization was carried out to reduce NOx emissions from the final design. The final combustion chamber was successfully tested and demonstrated in a gas turbine.