Abstract: Using numerical simulation technology,a cold-state numerical simulation study is carried out on an afterburner with lobe-shaped mixer,and the flow field characteristic parameters such as temperature field,velocity field and pressure field are obtained. The research results show that,after the inner and outer culvert airflow enters the lobe-shaped mixer,it can be fully mixed,and the temperature distribution is gradually uniform. The low-speed zone formed at the rear of the flame stabilizer is conducive to flame generation and propagation. Inside the combustion chamber,the pressure distribution along the gas flow direction gradually tends to be uniform. Through the numerical simulation of this type of afterburner,the internal flow field distribution is familiarized,and its cold working characteristics are clarified.