How can I take advantage of the capabilities of a cluster I'm developing a model in C, and I need to run a couple of simulations (lengthy, and heavy ones). I seem to have a cluster at my disposal, but I'm not very familiar with the concept. I understand that there are different "nodes" ? My program is not designed to take advantage of this individually - it can't event take advantage of multiple processors, because the calculations have to be done in sequence. But I have to run multiple instances of the program, and I was hoping there'd be a way to run them on separate "nodes" (?) to avoid them having to share CPU time too much.

What I know : the cluster runs Red Hat Enterprise Linux for Servers 5.3.

Can anyone help?
According to my experience, clusters usually work like this: you submit a job to it (a program), and it allocates a node to run your job. You don't worry about allocating the nodes yourself.

So in your case, simply submit multiple jobs (usually they provide some method to submit batch jobs), and the cluster will allocate different nodes to each of them.