Abstract: A combustor of tumbling flow and recirculating flow was designed to satisfy the need of compact structure of diesel engine and to solve driving power shortage problem in the plateau with gas turbocharging system. Firstly, the internal temperature field and exit temperature distribution were analyzed by CFD numerical simulation and the main structural parameters of the combustion chamber were determined. Then the cold flow field of the combustor's dome was measured by the particle image velocimetry (PIV) to testify the tumbling flow, recirculating flow and capable steady blaze sections existing in the combustor's dome. Finally, a combustion experiment was implemented to analyze the oil deficient ignition and flameout. Experimental results show that, in a certain flow range, the gas oil ratio of both lean ignition and lean blowout is proportion to Mach number. Compared the total pressure recovery coefficient of the designed combustor with that of a same-sized recirculating-flow combustor, in the same flow, the total pressure of the designed combustor can increase by an average 2%.