UDS gradient ??
 

Previously i was trying to compute gradient of a UDM, but as i understand UDS gradients are pre-calculated by Fluent. And for post-processing, I want to store this gradient value in a UDM.

C_UDSI(c,t,RK) = SQRT(C_UDSI(c,t,K);

C_UDMI(c,t,DE) = SQR(C_UDSI_G(c,t,RK)[1]);

here, 'k' is the scalar for which transport eqns are being solved, and i need to compute the y-direction gradient of sqrt(k). 'de' is the UDM which i have created to store the square of this gradient value.

On compiling the UDF, I am getting an error in the second line

error C2109: subscript requires array or pointer type

Kindly tell me what i may be doing incorrectly, or alternatively any other method of computing gradient of a UDS...

Thanks a lot in advance..