How does the thermal efficiency of an ideal cycle, in general, compare to that of a Carnot cycle operating between the same temperature limits?

Rankine cycle less efficient as compare to Carnot cycle operating betwwen same temperature limit.

Explanation:

We know that Carnot's cycle is an ideal cycle for all heat engine which operating between same temperature. It is a reversible cycle which have all process reversible that is why it have maximum efficiency.

On the other hand Rankine cycle is a practical working cycle so it is impossible to make all process reversible. In practical there will be always loss due to this any process can not make 100 % reversible. That is why Rankine cycle have low efficiency as compare to Carnot cycle operating between same temperature limits.