Abstract: A series of experiments of flame stability in ceramic evaporaton cavity with different porosity at different osmotic oil flow rate have been completed in a model afterburner.Experimental results show that,in the case of the main oil supply only or with osmotic oil supply,there is an optimal porosity respectively,where extinction limit of lean poor mixed gas is the widest,with the osmotic oil suuly only,flame extinction limit of ceramic holder becomes wider as the porosity increases.Concerning the effect of the osmotic oil flow rate on the flame stability,the extinction limit becomes extended usually as the osmotic oil flow rate increases.