Research Of Multifunctional Biomass Gasification Stove

After entering the21^st century, many issues including the shortage of energy and thepollution of environment are faced by all nations and required solutions urgently. Relativelypositive actions are being done. Being friendly to environment and with no location limitsare the main advantages of biomass energy, so it is paid more attentions. China, as a greatcountry of agriculture and forestry, possesses significant amount of the biomass energy.However, most of the biomass energy is used in a traditional way in countryside. The energyefficiency is so poor that the devices which could insure biomass energy used efficiently andclearly should be spread widely, which can promote the economy and accelerate thecountryside building.The problems, involving single function, low energy efficiency and the instablegasification and burning under a high power working condition, are analyzed in this paper.To solve those issues, we have improved the multifunction biomass stove which wasdesigned and manufactured by the researchers from Thermal Engineering at Jilin University,according to the burning characteristics of corncob. This stove can work in two mode-gasification mode and burning directly mode, possesses multifunction-cooking, heating, bath,etc.In this thesis, we mainly research the biomass gasified stove. On the testing bench,many performances of the stove were tested, such as heat engineering, emission, gasification,etc. The results reveal that the stove’s working condition under high power and natureventilation could be optimized by varying the thickness of the fuel and the opening of theflue valve. Under the best condition, the effective power and heat efficiency could reach thedesign target, even though companying by little higher CO in the exhaust smoke. Under alow power working condition, through changing the quantity of gasification agent tomeasure heat input strength of the fuel. In the best quantity of gasification agent case, theheat input strength is closed to the target value. The main reason of the difference is diffusion burning. The fire is large and high, the released heat could not be used efficiently,which is the main reason why the heat input strength is lower than the design value.We researched the causes of relatively large quantity of CO in the exhaust smoke underhigh power condition by CFD. The software-Fluent6.0-was used to simulate the air flow in acooling condition. From the results, many areas no air flow zone were detected, which causethe volatilizations could not mix with the air in the stove absolutely. Then it results inincompletely burn and the high level CO in the exhaust smoke. To increase the turbulence inthe stove, three kinds of fire channel were designed and separated CFD simulations wereconducted. The results showed that new fire channels reduce the no flow zones and theturbulence was enhanced. The experiments of the remodel indicated that the heat efficiencieshave been raised by4%and to76.92%, the CO went down under600ppm, indicating thechanging did work.All in all, in order to improve the flaming, the emission and the heat transfer, thecombination of experiments and simulation was conducted in the research of multifunctionbiomass stove. All of this is valuable for future design and operation management of biomassstove.