Self-ignition and special features of flow in a planar vortex chamber

Regular self-ignition of hydrogen and kerosene was registered upon their mixing with oxygen-enriched air in a straight-flow vortex chamber of planar-radial geometry. These fuel components were injected into the chamber from tanks with room temperature and pressure 4-10 MPa. The velocity pressure, and temperature fields in the chamber were studied using experimental methods and numerical modeling on the basis of full Navier-Stokes equations. The measurement and calculation showed that a region of elevated temperatures appears in an unsteady vortex flow. The calculation was performed for Reynolds numbers up to 5 . 10(3) and revealed an increase in temperature with increase in Reynolds number. Nevertheless, both the calculated and measured temperatures were lower than the known self-ignition temperatures. The nature of the ignition observed remains unclear.