CALORIMETRIC STUDY OF BURNERS USED IN FLAME-JET DRILLING

The present paper focuses on an experimental technique for testing of the thermal performance of rocket-jet burners used in thermal spallation drilling independently of the rock type. The ability of these burners to create large cavities or to get faster penetration rates in rocks is characterized by quantifying the surface heat fluxes around the flame. A hollow-cylinder shaped calorimeter was developed, that permits the surface temperature histories to be measured. The measured temperatures serve as boundary conditions for the solution of the transient heat conduction problem numerically that ultimately supplies the surface heat fluxes as well.