Numerical assessment of spacer grid geometry on turbulence anisotropy in a rod bundle

Open Access

Symboles table

Symbole	Variable	Units
a_ij	Anisotropic part of < u′_iu′_j>	m²/s²
b_ij	Normalised a_ij
C_w	WALE model constant
C_1c	First anisotropy weight
C_2c	Second anisotropy weight
C_3c	Third anisotropy weight
Dh	Hydraulic diameter	m
$\bar{g_{ij}}$ $Mathematical equation: $ \bar{g_{ij}} $$	Filtered velocity gradient tensor	s⁻¹
I	Turbulence intensity
k	Turbulence kinetic energy	m²/s²
k_r	Residual kinetic energy	m²/s²
l	Edge size of a cell face	m
L	Length scale for large eddies	m
L_int	Integral length scale	m
L_zz	Integral length scale based on R_zz	m
P	Pressure field	Pa
$\bar{P}$ $Mathematical equation: $ \bar{P} $$	Filtered pressure field	Pa
R	Radius	m
R_zz	Auto-correlation function of < u′_z>	m²/s²
Re	Reynolds number
Re_bulk	Reynolds number based on U_bulk
Re_L	Reynolds number based on L
Re_λ	Reynolds number based on λ
$\bar{S_{ij}}$ $Mathematical equation: $ \bar{S_{ij}} $$	Filtered rate of strain tensor	s⁻¹
S_ij^d	Traceless symmetric part of $\bar{g_{ij}}$ $Mathematical equation: $ \bar{g_{ij}} $$	s⁻²
u	Residual velocity	m/s
u′	Velocity fluctuations	m/s
U	Velocity field	m/s
< U>	Averaged velocity field	m/s
$\bar{U}$ $Mathematical equation: $ \bar{U} $$	Filtered velocity field	m/s
U_bulk	Bulk velocity	m/s
u_τ	Friction velocity	m/s
u⁺	Mean velocity normalised by u_τ
< u′_iu′_j>	Reynolds stress tensor	m²/s²
y⁺	Normalised distance from the wall
δ_ij	Kronecker symbol
Δ	Subgrid characteristic length scale	m
Δ_x	Gap between cells on x-axis	m
Δ_z	Gap between cells on z-axis	m
Δ_x⁺	Normalised Δ_x
Δ_z⁺	Normalised Δ_z
ϵ	Turbulence dissipation rate	m²/s³
λ	Taylor micro scale	m
λ₁	Highest b_ij eigenvalue
λ₂	Second highest b_ij eigenvalue
λ₃	Lowest b_ij eigenvalue
ν	Viscosity	m²/s
ν_t	Eddy viscosity	m²/s
ρ	Density	kg/m³
τ	Decay rate	s
τ_ij^r	Sub grid scale	m²/s²
τ_ij^R	Residual stress tensor	m²/s²
τ_w	Wall shear stress	Pa

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.