Physics Asked on January 6, 2022
Thermionic Conversion follows the classic Richardson-Dushmann Equation for thermionic current as a function of temperature squared:
$$J_{RD} = A_0 T^2 expleft(-frac{phi}{k_B T}right)$$
where
But thermal power loss is a function of the fourth power of temperature following the Stefan-Boltzmann law:
begin{equation}
P=Asigma T^4
end{equation}
where
Although I see a lot of talk about space charge buildup being the limiting factor on thermionic conversion efficiency, the power of 2 disadvantage from thermal radiation losses seems to make thermionic conversion a fundamentally impractical approach to approximating Carnot efficiency.
What am I missing?
According to this article, "Thermionic Energy Conversion in the Twenty-first Century: Advances and Opportunities for Space and Terrestrial Applications", the thermal radiation actually is a design concern.
You mention two power laws, and yes it does imply that at high temperatures the efficiency must drop, but it also equally implies that at low enough temperatures, the effect of the thermal radiation must become negligible.
The power of the power law is not the only thing, and in evaluating whether a technology sinks or swims, it comes down to a practical question of what are the actual coefficients, etc., and what is the final tradeoff that gets made in engineering.
Answered by Nanite on January 6, 2022
2 Asked on February 12, 2021 by sylvia
1 Asked on February 12, 2021
1 Asked on February 12, 2021 by induvidyul
1 Asked on February 12, 2021 by gigino
0 Asked on February 12, 2021 by asplund
5 Asked on February 12, 2021 by gil-kalai
conformal field theory probability research level statistical mechanics
1 Asked on February 12, 2021
2 Asked on February 12, 2021 by strangequirks
2 Asked on February 12, 2021 by coby1kenobi
0 Asked on February 12, 2021
charge electric fields electrostatics forces potential energy
2 Asked on February 12, 2021 by wilada
antimatter charge elementary particles particle physics quarks
1 Asked on February 12, 2021 by lucenalex
field theory solitons topological defects topological field theory
3 Asked on February 11, 2021
astrophysics cosmological constant cosmology space expansion
4 Asked on February 11, 2021 by monopole
1 Asked on February 11, 2021 by mohamed-obeidallah
2 Asked on February 11, 2021 by biology12323
1 Asked on February 11, 2021 by sean-e-lake
dipole electromagnetism neutrons particle physics polarization
0 Asked on February 11, 2021 by bruce-smitherson
Get help from others!
Recent Answers
Recent Questions
© 2023 AnswerBun.com. All rights reserved. Sites we Love: PCI Database, MenuIva, UKBizDB, Menu Kuliner, Sharing RPP, SolveDir