In using a vortex method for the protection of gas burners from coking process the stability of an annular vortex has been studied. An experimental device and measuring instruments have been described. Optical qualitative investigations into efflux of flat jets into cross flow have been carried out and statistical analysis of pressure pulsations at the mouth of a jet for chennals of three types has been made. Conditions, under which mouth of jets at the stable circulating flows stagnant zone formations may exist, have been identified. To prevent the coking process at the outlets of gas distribution burner openings oriented at an angle to cross flow the diffuser section is proposed to be with an axis which should be inclined towards the axis of an opening along the cross flow.