Based on the idea of single cavity trapped vortex combustor, a advanced vortex combustor which is constitute by three blunt bodies and double concave cavity is proposed. And the interior combustor flow characteristics are analyzed. The results shows that the flow field characteristics changed a lot before and after combustor modification, and D2=20mm, D3=4mm are respectively the best modification scheme on the second and third blunt body.

Three-dimensional numerical study is performed for heat transfer and resistance characteristics as well as comprehensive performance of two kinds H-type (single and double) finned tube. It is found that the heat transfer and resistance characteristics as well as comprehensive performance of H-type finned tube are influenced by the Reynolds number of gas. With the growth of Reynolds number, the air-side Nusselt number rises gradually and the heat transfer performance gets better and better, whereas the air-side Euler number drops step by step until close to a fixed value. The comprehensive performances of both single H-type finned tube and double ones are weaken progressively. When Reynolds number value is same, the convective heat transfer, pressure drop, air-side Nusselt number and Euler number of single H-type finned tube are bigger than those of double ones. The single H-type finned tube expression is much better than double ones in comprehensive performance and heat transfer.

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Dynamic mesh and moving wall technique were employed to simulate the unsteady flow field of moving particle with finite size. For freely moving particle, it does not come into being particle wake. Middle particle can move straightforward outlet, but left and right particles move disorderly in a restricted region. Vortex location varies with the change of particle location. Turbulence energy and pressure is decreased gradually from inlet to outlet. But for moving particle with slip velocity between gas and particle, particle wake comes into being. Turbulence enhancement by particle wake effect is studied by numerical simulation of gas turbulent flows passing over particle under various particle sizes, inlet gas velocities, gas viscosity, gas density and the distance of particles.