An experimental investigation into the effects of side load and heating orientation on the critical heat flux of flow boiling in a narrow rectangular groove was performed with a rotational platform. Using distilled water as working fluid

the change trend of mass velocity

the pressure drop in test section and its outlet wall temperature before and after reaching critical heat flux were obtained

the effects of side load and heating orientation on critical heat flux were investigated at different mass velocities

inlet temperatures

dynamic loads and heating orientations. Flow instability was briefly analyzed. The results show that in addition to the rapid wall temperature rise

the effective heat flux decreases as the critical heat transfer occurs. The pressure drop in test section decreases and mass velocity rebounds obviously after power cutoff. The effects of side load and heating orientation on critical heat flux are obvious. Not soon before and after the critical heat transfer occurs

the back flowing vapor increases the inlet fluid temperature

thus enhancing the flow instability.