This is the code I'm using to GET the values into an array:
NSEL,S,NODE,,nolatu
*DIM,u,ARRAY,15
SHELL,BOT
j=1
*DO,i,1,15,3
LAYER,j
*GET,u(i),NODE,nolatu,U,X
j=j+1
*ENDDO
SHELL,MID
j=1
*DO,i,2,15,3
LAYER,j
*GET,u(i),NODE,nolatu,U,X
j=j+1
*ENDDO
SHELL,TOP
j=1
*DO,i,3,15,3
LAYER,j...