nabla differential operator |
; and ; | covariant and contravariant differential operators |
f | gradient of scalar f |
A | divergence of tensor A |
A | curl of tensor A |
, ii , ii | Laplacian operator |
v , ivj | velocity gradient tensor |
, (subscript) | partial derivative with respect to following index(es) |
; (subscript) | covariant derivative with respect to following index(es) |
hat (e.g. Ai , Ei ) | physical representation or normalized vector |
bar (e.g. ui , Ai ) | transformed quantity |
inner or outer product operator |
perpendicular to |
1D, 2D, 3D, n D | one-, two-, three-, n -dimensional |
t | absolute derivative operator with respect to t |
i and i | partial derivative operator with respect to ith variable |
;i | covariant derivative operator with respect to ith variable |
[ij,k] | Christoffel symbol of 1st kind |
A | area |
B , Bij | Finger strain tensor |
B1 , Bij1 | Cauchy strain tensor |
C | curve |
Cn | of class n |
d , di | displacement vector |
det | determinant of matrix |
diag [ ] | diagonal matrix with embraced diagonal elements |
dr | differential of position vector |
ds | length of infinitesimal element of curve |
d | area of infinitesimal element of surface |
d | volume of infinitesimal element of space |
ei | ith vector of orthonormal vector set (usually Cartesian basis set) |
er,e,e | basis vectors of spherical coordinate system |
err,er,,e | unit dyads of spherical coordinate system |
e,e,ez | basis vectors of cylindrical coordinate system |
e,e,,ezz | unit dyads of cylindrical coordinate system |
E , Eij | first displacement gradient tensor |
Ei , Ei | ith covariant and contravariant basis vectors |
i | ith orthonormalized covariant basis vector |
Eq./Eqs. | Equation/Equations |
g | determinant of covariant metric tensor |
g | metric tensor |
gij , gij , g ji | covariant, contravariant and mixed metric tensor or its components |
g11,g12,gnn | coefficients of covariant metric tensor |
g11,g12,gnn | coefficients of contravariant metric tensor |
hi | scale factor for ith coordinate |
iff | if and only if |
J | Jacobian of transformation between two coordinate systems |
J | Jacobian matrix of transformation between two coordinate systems |
J1 | inverse Jacobian matrix of transformation |
L | length of curve |
n , ni | normal vector to surface |
P | point |
P(n,k) | k -permutations of n objects |
qi | ith coordinate of orthogonal coordinate system |
qi | ith unit basis vector of orthogonal coordinate system |
r | position vector |
Ricci curvature scalar |
Rij , R ij | Ricci curvature tensor of 1st and 2nd kind |
Rijkl , R ijkl | Riemann-Christoffel curvature tensor of 1st and 2nd kind |
r,, | coordinates of spherical coordinate system |
S | surface |
S , Sij | rate of strain tensor |
S , Sij | vorticity tensor |
t | time |
T (superscript) | transposition of matrix |
T , Ti | traction vector |
tr | trace of matrix |
ui | ith coordinate of general coordinate system |
v , vi | velocity vector |
V | volume |
w | weight of relative tensor |
xi , xi | ith Cartesian coordinate |
x i , xi | ith Cartesian coordinate of particle at past and present times |
x,y,z | coordinates of 3D space (mainly Cartesian) |
, ij | infinitesimal strain tensor |
rate of strain tensor |
kij | Christoffel symbol of 2nd kind |
Kronecker delta tensor |
ij , ij , ji | covariant, contravariant and mixed ordinary Kronecker delta |
ijkl , ijklmn , i1inj1jn | generalized Kronecker delta in 2D, 3D and n D space |
, ij | second displacement gradient tensor |
ij , ijk , i1in | covariant relative permutation tensor in 2D, 3D and n D space |
ij , ijk , i1in | contravariant relative permutation tensor in 2D, 3D and n D space |
ij , ijk , i1in | covariant absolute permutation tensor in 2D, 3D and n D space |
ij , ijk , i1in | contravariant absolute permutation tensor in 2D, 3D and n D space |
, | coordinates of plane polar coordinate system |
,,z | coordinates of cylindrical coordinate system |
, ij | stress tensor |
vorticity tensor |
region of space |