In a cold-state test furnace with height of 2680 mm and diameter of 440 mm

a test of flow field and concentration distribution of tracer gas CO has been carried out for two gasification nozzles of new type with five channels and in the outer most channel the incidence angle α is 30° and 32 ° respectively

the regularity of incidence angle's influence upon the flow field distribution

the change of back flow rate

and the concentration distribution of tracer gas being analysed.Results show that the back flow region and the back flow rate produced by the nozzle with incidence angle α=32° all are greater than that produced by nozzle with incidence angle α=30°;the influence of different incidence angles upon the gas concentration distribution is smaller

the tow kinds of nozzle all entered into fully mixed region at height/diameter ratio is equal to 2.07.The nozzle with incidence angle of 32° is more advantageous for effectively carrying out the gasification process.