Abstract: This study presents a novel rotating detonation combustor configuration with continuously adjustable inlet areas to improve the operational flexibility of turbine-based rotating detonation engines. The modal evolution in the combustor, the inlet blockage characteristics, and the combustor’s performance during the continuous inlet area adjustment have been systematically examined by experiments. By varying the inlet area and equivalence ratio, three typical operational modes are identified: rotating detonation, axial pulse detonation, and deflagration. Notably, the combustor maintains its initial operation mode when the inlet area is continuously adjusted follwing the initiation. The inlet air blockage ratio increases with a decreasing nozzle-to-inlet area ratio and an increasing equivalence ratio. The enhanced inlet blockage reduces the inlet air pressure ratio, thereby strengthening the coupling between the gas plenum and the combustor. Under stable operation states, the continuous adjustable condition and the fixed-area condition yield the same inlet blockage ratio. However, due to the pressure response delay in the combustor and the gas plenum to the inlet area adjustment, the continuously adjustable condition eventually leads to a higher inlet blockage ratio. When the nozzle-to-inlet area ratio decreases due to the pressure response delay, the combustion efficiency temporarily exceeds that of the fixed-area condition during the adjustment process, eventually recovering to the fixed-condition value after the adjustment process. Meanwhile, the total pressure recovery coefficient gradually increases, but remains comparable to that under fixed-working conditions throughout the adjustment process. These experimental findings establish a fundamental basis for developing adaptive control methodologies for rotating detonation combustors under variable operating conditions, significantly enhancing their engineering viability for turbine engine applications.