@article{hanquist2019c,
	title = {Plasma {Assisted} {Cooling} of {Hot} {Surfaces} on {Hypersonic} {Vehicles}},
	volume = {7},
	doi = {10.3389/fphy.2019.00009},
	abstract = {Electron transpiration cooling (ETC) is a proposed thermal management approach for the leading edges of hypersonic vehicles that utilizes thermionic emission to emit electrons to carry heat away from the surface. A modeling approach is presented for assessing ETC in a computational fluid dynamics (CFD) framework and is evaluated using previously completed experiments. The modeling approach presented includes developing boundary conditions to account for space-charge-limited emission to accurately determine the level of electron emission from the surface. The effectiveness of ETC for multiple test cases are investigated including sharp leading edges and blunt bodies. For each of these test cases, ETC affects the surface properties, most notably the surface temperature, suggesting that ETC occurs for bodies in thermally intense, ionized flows, no matter the shape of the leading edge. An approximate approach is also presented to assess ETC in an ionized flow and compares its cooling power to radiative cooling.},
	number = {9},
	journal = {Frontiers in Physics: Plasma for Aerospace},
	author = {Hanquist, Kyle M. and Boyd, Iain D.},
	year = {2019},
	keywords = {Computational fluid dynamics, Electron transpiration cooling, Hypersonics, Plasma sheath, Thermionic emission, etc, own},
	pages = {1--13},
}

Electron transpiration cooling (ETC) is a proposed thermal management approach for the leading edges of hypersonic vehicles that utilizes thermionic emission to emit electrons to carry heat away from the surface. A modeling approach is presented for assessing ETC in a computational fluid dynamics (CFD) framework and is evaluated using previously completed experiments. The modeling approach presented includes developing boundary conditions to account for space-charge-limited emission to accurately determine the level of electron emission from the surface. The effectiveness of ETC for multiple test cases are investigated including sharp leading edges and blunt bodies. For each of these test cases, ETC affects the surface properties, most notably the surface temperature, suggesting that ETC occurs for bodies in thermally intense, ionized flows, no matter the shape of the leading edge. An approximate approach is also presented to assess ETC in an ionized flow and compares its cooling power to radiative cooling.

@article{digiorgio2019,
	title = {An aerothermodynamic design optimization framework for hypersonic vehicles},
	volume = {84},
	doi = {10.1016/j.ast.2018.09.042},
	abstract = {In the aviation field great interest is growing in passengers transportation at hypersonic speed. This requires, however, careful study of the enabling technologies necessary for the optimal design of hypersonic vehicles. In this framework, the present work reports on a highly integrated design environment that has been developed in order to provide an optimization loop for vehicle aerothermodynamic design. It includes modules for geometrical parametrization, automated data transfer between tools, automated execution of computational analysis codes, and design optimization methods. This optimization environment is exploited for the aerodynamic design of an unmanned hypersonic cruiser flying at M∞=8 and 30 km altitude. The original contribution of this work is mainly found in the capability of the developed optimization environment of working simultaneously on shape and topology of the aircraft. The results reported and discussed highlight interesting design capabilities, and promise extension to more challenging and realistic integrated aerothermodynamic design problems.},
	journal = {Aerospace Science and Technology},
	publisher = {Elsevier Masson SAS},
	author = {Di Giorgio, Simone and Quagliarella, Domenico and Pezzella, Giuseppe and Pirozzoli, Sergio},
	month = jan,
	year = {2019},
	keywords = {CST, Design optimization, Evolutionary strategies, Hypersonics},
	pages = {339--347},
}

In the aviation field great interest is growing in passengers transportation at hypersonic speed. This requires, however, careful study of the enabling technologies necessary for the optimal design of hypersonic vehicles. In this framework, the present work reports on a highly integrated design environment that has been developed in order to provide an optimization loop for vehicle aerothermodynamic design. It includes modules for geometrical parametrization, automated data transfer between tools, automated execution of computational analysis codes, and design optimization methods. This optimization environment is exploited for the aerodynamic design of an unmanned hypersonic cruiser flying at M∞=8 and 30 km altitude. The original contribution of this work is mainly found in the capability of the developed optimization environment of working simultaneously on shape and topology of the aircraft. The results reported and discussed highlight interesting design capabilities, and promise extension to more challenging and realistic integrated aerothermodynamic design problems.

@article{schwartzentruber2007,
	title = {A modular particle-continuum numerical method for hypersonic non-equilibrium gas flows},
	volume = {225},
	doi = {10.1016/j.jcp.2007.01.022},
	abstract = {A modular particle-continuum (MPC) numerical method for steady-state flows is presented which solves the Navier-Stokes equations in regions of near-equilibrium and uses the direct simulation Monte Carlo (DSMC) method to simulate regions of non-equilibrium gas flow. Existing, state-of-the-art, DSMC and Navier-Stokes solvers are coupled together using a novel modular implementation which requires only a limited number of additional hybrid functions. Hybrid functions are used to adaptively position particle-continuum interfaces and update boundary conditions in each module at appropriate times. The MPC method is validated for 2D flow over a cylinder at various hypersonic Mach numbers where the global Knudsen number is 0.01. For the cases considered, the MPC method is verified to accurately reproduce DSMC flow field results as well as local particle velocity distributions up to 2.2 times faster than full DSMC simulations. © 2007 Elsevier Inc. All rights reserved.},
	number = {1},
	journal = {Journal of Computational Physics},
	author = {Schwartzentruber, T. E. and Scalabrin, L. C. and Boyd, I. D.},
	year = {2007},
	keywords = {DSMC, Direct simulation Monte Carlo, Hybrid particle-continuum, Hypersonics, Non-equilibrium flow, Rarefied flow, Re-entry vehicles},
	pages = {1159--1174},
}

A modular particle-continuum (MPC) numerical method for steady-state flows is presented which solves the Navier-Stokes equations in regions of near-equilibrium and uses the direct simulation Monte Carlo (DSMC) method to simulate regions of non-equilibrium gas flow. Existing, state-of-the-art, DSMC and Navier-Stokes solvers are coupled together using a novel modular implementation which requires only a limited number of additional hybrid functions. Hybrid functions are used to adaptively position particle-continuum interfaces and update boundary conditions in each module at appropriate times. The MPC method is validated for 2D flow over a cylinder at various hypersonic Mach numbers where the global Knudsen number is 0.01. For the cases considered, the MPC method is verified to accurately reproduce DSMC flow field results as well as local particle velocity distributions up to 2.2 times faster than full DSMC simulations. © 2007 Elsevier Inc. All rights reserved.