Table 1.

Nomenclature.

$A$	cross-section area of corona discharge (m2)
$C_D$	drag coefficient of the cathode
$D_e$	ion diffusivity (m2 s−1)
$D_k$	ion diffusivity of charged species k (m2 s−1)
$d$	distance between anode and cathode (mm)
$E$	electric field (V m−1)
$f$	Coulomb force per unit volume (N m−3)
$F_{\mathrm{EHD}}$	volumetric force induced by ions (N)
$F_D$	drag force (N)
$I$	current (A)
$J$	current flux [C/(s•m2)]
$J_L$	current flux at characteristic length scale [C/(s•m2)]
$k_B$	Boltzmann constant
$L_c$	characteristic dimension
$N_k$	density of charged species k
$P$	pressure inside a corona discharge (Pa)
$q$	elementary charge (C)
$S$	cross-sectional area of the cathode (m2)
$T$	thrust force induced by the ions (N)
$T_e$	absolute temperature (K)
$u$	velocity (m s−1)
$v$	mean electric wind velocity (m s−1)
$\beta$	scaling factor for the characteristic length
$\epsilon$	permittivity of air [C/(V•m)]
${\mu }_b$	ion mobility [m2/(V•s)]
${\mu }_k$	ion mobility of charged species k [m2/(V•s)]
${\rho }_e$	charge density (C m−3)
$\rho$	density of fluid (kg m−3)
$\theta$	non-dimensionless quantity for the drag force
$\phi$	electric potential (V)
${\phi }_o$	corona initiation voltage (V)
${\omega }_k$	production rate of charged species