The flow instability with a type of thermo-acoustic oscillation of aviation kerosene at supercritical pressures in a vertical upward circular tube was investigated. The formation mechanism and development process of thermo-acoustic oscillation were revealed based on the boundary layer theory. The effect mechanisms of operational parameters on thermo-acoustic oscillation border were analyzed. The prediction criterion for thermo-acoustic oscillation border was established by the sub-pseudo-critical number and trans-pseudo-critical number. The prediction problem for final state heat transfer of thermo-acoustic oscillation was solved. Results indicate that the stable flow and thermal boundary layers are destroyed owing to the drastic thermo-properties fluctuations. They lead to the thermo-acoustic oscillation flow instability phenomenon with enhanced heat transfer capability. The critical heat flux of thermo-acoustic oscillation increases with the increasing mass flow rate and inlet temperature. The thermo-properties variations tend to gentle as the pressure increases

hence the flow stability is enhanced and the thermo-acoustic oscillation does not appear easily. The critical trans-pseudo-critical number for thermo-acoustic oscillation approximately linear decreases with the increasing sub-pseudo-critical number. It consequently provides a discriminating criterion to avoid the flow instability phenomenon.