Of course, one of the best examples is extended surfaces of tube banks inside convection section of process fired heaters. Specifically studs and helical fins.
Simulating heat transfer phenomena in fired heater tube banks was and will remain as a challenge for engineers. As you know better than me most of the existing methods are purely empirical and any theoretical progress in this field would be warmly welcomed by engineering community. The same rule applies to shell and tube heat exchangers.