[R] CFD Plots in R and Other Things

[Lorenzo Isella]

Dear All,

I am getting some data from fluid dynamics simulations (air mixing in
a pipe, 2D axial symmetry, geometry described by a radial coordinate r
and an axial coordinate z) which I'd like to plot and analyze with R.
Think about slicing the cylinder along its axial direction to get a
set of cross sections which are orthogonal to the z axis.
For each section, I have a set of velocity readings, i.e. the data I
would like to plot are in the form:

           v_11 v_12  v_13 ..... v_1n
           v_21 v_22  v_23 ..... v_2n
           ......................................
           v_m1 v_m2  v_m3 ..... v_mn

where v_ij is the velocity reading on the i-th position along z and
the j-th position along r.
Tipically, these sets of data are plotted in 2D with r and z as axis
and the velocity  field represented by using colours explained by a
legenda.
Can R do anything like this?
Second (and much simpler question): I have a list of data which I can
plot easily, but I would like to have the time during the day to label
the x axis (starting from 19:00 for forty hours).
How can I do that?
Many thanks

Lorenzo