Thermochromic liquid crystal (TLC) was used in the transient heat transfer experiments of rotor-stator cavity with central inlet and small mass flow rate. The effects of mass flow rate and rotation speed on rotary disk were studied. Results showed that

under the conditions concerned

changes of mass flow rate had a great impact on heat transfer in mid-radius and lower-radius region

and had a less impact on higher-radius region; increase of rotation speed intensified the heat transfer over the rotary disk; Nusselt number over the mid-radius and higher-radius region increased with radius when turbulent flow parameter was low; the experimental results were correlated by turbulent flow parameter and compared with results from Reynolds analogy

and the difference was less than 15%

verifying the applicability of Reynolds analogy on rotor-stator cavity to a certain extent.