Do you need to wipe data when flashing kernels ? No. You shouldn't need to wipe cache/Dalvik either, though do it if the developer of the kernel says to in the flashing instructions for the kernel.
How to determine rom compatibility for a kernel ? Read the first page of the thread devoted to the kernel. Should tell you what it's compatible with, if it doesn't, ask in the kernel thread. The worst thing that can happen if you flash & it isn't compatible is you'll end up with bootloop. Unlikely to brick your phone outright unless you're one of the 0.000001% of people who end up with a bad flash full stop.