# ion_thermal_conductivity¶

plasmapy.formulary.ion_thermal_conductivity(T_e, n_e, T_i, n_i, ion, m_i=None, Z=None, B: Unit("T") = <Quantity 0. T>, model='Braginskii', field_orientation='parallel', mu=None, theta=None, coulomb_log_method='classical') -> Unit("W / (K m)")

Calculate the thermal conductivity for ions.

The ion thermal conductivity ($$κ$$) of a plasma is defined by

$κ = \hat{κ} \frac{n_i k_B^2 T_i τ_i}{m_i}$

where $$\hat{κ}$$ is the non-dimensional ion thermal conductivity of the plasma, $$n_i$$ is the ion number density of the plasma, $$k_B$$ is the Boltzmann constant, $$T_i$$ is the ion temperature of the plasma, $$τ_i$$ is the fundamental ion collision period of the plasma, and $$m_i$$ is the mass of an ion of the plasma.

Notes

This is the classical plasma ions’ ability to conduct energy and heat, defined similarly to other materials. The result is a conductivity in units of W / m / K, so if you assume you know where the heat is flowing (temperature gradient, cross-sectional area) you can calculate the energy transport in watts as conductivity × cross-sectional area × temperature gradient. In laboratory plasmas, typically the energy is flowing out of your high-temperature plasma to something else, like the walls of your device, and you are sad about this.

Returns

Return type

Quantity