The tar decomposition of low-pressure ejection type burner was researched. The burner used software to simulate and analyse impact of the nozzle diameter d, the gas flow rate V and the distance of the nozzle to the wall L on tar cracking. The orthogonal test were used for design parameters d, V and L, the optimization values of these three parameters were carried out, and experimental method was used for test the numerical simulation results. Numerical simulation and experimental results showed that the greatest impact on tar cracking is the nozzle diameter d, the minor effect is the distance of the nozzle to the wall L and the weakest effect is the gas flow rate V, and when the nozzle diameter d=4 mm, the distance L=18 mm and the gas flow rate V=0.10 m3/h, the tar cracking is the most efficiency.

The mixed arrangement irregular heat-pipe flue gas heat transfer was researched, using numerical simulation method. The irregular heat-pipe: triangle heat pipe; square heat pipe. The heat pipe equivalent diameter of flue gas heat transfer is 20 mm, the speed of inlet flue gas is 11 m/s, the inlet temperature of flue gas is 500 K. the results show mixed arrangement irregular heat-pipe can enhance heat exchanging, the optimal parameters of mixed arrangement structure in the condition of given working condition: the first row is triangle heat pipe, the second row is circular heat pipe, the third row is triangle heat pipe, row 4 is square heat pipe, the line spacing of the first row and second is 40 mm, the line spacing of the second and third row is 40 mm, the line spacing of the third row and the fourth row is 35 mm, and the row spacing of the tube is 40 mm. the heat transfer efficiency of the optimized irregular heat-pipe-exchanger raised 40 ~ 60%.

With dry woody particles as fuel and air-steam as gasification agent, the higher heating value biomass gas gasifier used software to simulate the height position h of the steam from the entrance in the gasifier, the steam inlet flow rate Vs and the air inlet flow rate V0. These three parameters impact on the volume concentration of CO, H2 and CH4 and its gas calorific value were analyzed. The orthogonal test were used for design parameters h, Vs and V0, the optimization values of these three parameters were carried out, and test its volume concentration and gas calorific values. Numerical simulation and experimental results showed that when the height position h=180mm, air inlet flow rate V0=0.94m3/h, and steam inlet flow rate Vs=1.30m3/h, the combustion of biomass gas calorific value arrives its top, the value is Q=10.98MJ/m3, which is 114.87% higher than when single gas agent is used.

The array configuration of delta wing and elliptical cylinder vortex generator in the spiral surface channel was studied. By changing the assembly distance s, the triangle wing vortex generator angle of attack α, the elliptical cylinder vortex generator angle of attack β to research the heat transfer and resistance properties under different working conditions. The research model as follow: the heat-medium is water-vapor [H2, the cold medium of flow is air, Steam temperature is 400K and air inlet temperature is 293K, the Reynolds number ranging from 4000 to 7000.The optimum structure was determined by using numerical simulation method and orthogonal experiment method. The result shows the optimization structure of the combination vortex generator: α=45°, β=45°, s=90mm. Compared with the normal structure, the heat transfer enhancement comprehensive effect of the optimization structure raised about 36.2%~47.6%.

The semi-elliptic cylinder shell vortex generator set in the interpolation-tubular air pre-heater was studied. And by changing the high-width Ratiov, dip angleα, attack angleβ, spacingsof vortex generator to research the heat transfer and resistance properties under different working conditions, and the optimization structure of vortex generator was determined. The heating medium of the air pre-heater is the flue gas that passes across tube outside, and the cooling air as the cooling medium in the tube longitudinal scoured. The Reynolds number range is 25000 ~ 40000. The research shows that: semi-elliptic cylinder vortex generator can obviously improve the heat transfer performance, the optimization structure of the semi-elliptic cylinder vortex generator: high-width ratiov= 0.45, attack angleβ= 65 °, dip angleα= 15 °, spans= 90 mm, the heat transfer enhancement comprehensive effect raised about 43.2%~72.6%.