Related papers: Physics-based Model for Nonuniform Thermionic Elec…
Experimental observations have long-established that there exists a smooth roll-off or knee transition between the temperature-limited (TL) and full-space-charge-limited (FSCL) emission regions of the emission current density-temperature…
We use computational simulations to study the electron emission and propagation in planar vacuum diodes. We show how space-charge affects thermionic emission from cathodes with two different values of work function that form a checkerboard…
Thermionic emission from a polycrystalline tungsten emissive cathode immersed in a magnetized plasma column is investigated experimentally and numerically. Electrical and optical measurements of the cathode temperature show a highly…
Electron transpiration cooling (ETC) can reduce aerothermal loads on sharp hypersonic leading edges, but its performance is governed by whether thermionically emitted electrons escape the hot surface or return as cathode-directed backflow.…
In a current density versus temperature (J-T) (Miram) curve in thermionic electron emission, experimental measurements demonstrate there is a smooth transition between the exponential region and the saturated emission regions, which is…
A model of the collisional kinetics of energetic hydrogen atoms, molecules, and ions in pure H$_2$ discharges is used to predict H$_\alpha$ emission profiles and spatial distributions of emission from the cathode regions of low-pressure,…
Thermionic emission has been exploited to give rise to the theory of thermionic cooling also known as electron transpiration cooling, which can potentially serve as a powerful and engineerable cooling mode for hypersonic leading edges that…
In this paper, we propose a model to investigate the electron thermionic emission from a single-layer graphene (ignoring the effects of substrate) and to explore its application as the emitter of thermionic energy convertor (TIC). An…
The stationary thermionic electron emission currents from heated metals are compared against an analytical expression derived using a non equilibrium quantum Kappa energy distribution for the electrons. This later depends on the temperature…
This paper proposes a model that expands Godyak's collisional sheath model to the case of hot electrodes (anode or cathode) with thermionic electron emission. In the model, the electrodes are assumed to be made from refractory metals and,…
A model is constructed to describe the thermal-field emission of electrons from a three-dimensional ($3$D) topological semimetal hosting Dirac/Weyl node(s). The traditional thermal-field electron emission model is generalised to accommodate…
In this work, the thermionic cooling effect during thermionic discharges with parallel plate electrodes at 1 Torr is investigated. Time-resolved observation of electron emission and surface temperature is realized in addition to the typical…
We present the theory of out-of-plane (or vertical) electron thermal-field emission from 2D semimetals. We show that the current-voltage-temperature characteristic is well-captured by a universal scaling relation applicable for broad…
In this paper we propose new boundary conditions at the hot walls with thermionic electron emission for two-temperature thermal arc models. In the derived boundary conditions the walls are assumed to be made from refractory metals and that…
Numerical models of collisionless shocks robustly predict an electron distribution comprised of both thermal and non-thermal electrons. Here, we explore in detail the effect of thermal electrons on the emergent synchrotron emission from…
It is widely assumed that thermionic current flow through a plasma is limited by a "space-charge limited" (SCL) cathode sheath that consumes the hot cathode's negative bias and accelerates upstream ions into the cathode. Here, we formulate…
Electron emission from cathodes in high field gradients is a quantum tunneling effect. The 1928 Fowler-Nordheim field emission (FE) equation and the 1956 Murphy-Good FE equation have traditionally been key in describing cold field…
The methods of non-equilibrium thermodynamics of systems with an interface have been applied to the study of thermionic emission processes in abrupt semiconductor junctions, including the effects of surface states . Our analysis covers…
This study explores the transitional characteristics of blue-core helicon discharge, which to our knowledge was not particularly focused on before. Parameters are measured on recently built advanced linear plasma device, i.e. Multiple…
We study two techniques to create electrons in a liquid helium environment. One is thermionic emission of tungsten filaments in a low temperature cell in the vapor phase with a superfluid helium film covering all surfaces; the other is…