本文選題：內(nèi)循環(huán)流化床 + 顆�；旌���； 參考：《沈陽航空航天大學(xué)》2017年碩士論文

【摘要】：內(nèi)循環(huán)流化床在處理垃圾衍生燃料(RDF)燃燒方面具有獨特的優(yōu)勢,床內(nèi)氣固兩相流動特性直接影響相間傳熱傳質(zhì)以及化學(xué)反應(yīng)速率。本文著重研究了冷態(tài)隔板式內(nèi)循環(huán)流化床中單組分顆粒流動機(jī)制和雙組分顆粒混合特性,并通過計算流體力學(xué)耦合離散單元方法(CFD-DEM)對床內(nèi)顆粒運動的流場及混合進(jìn)行了數(shù)值模擬。其中歐拉方法處理連續(xù)氣相場的同時用拉格朗日方法直接跟蹤離散顆粒場的單個顆粒運動,從多組分顆粒層面對內(nèi)循環(huán)床內(nèi)混合機(jī)制進(jìn)行了研究。本文首先以Goldschmidt等人建立的三維矩形噴動流化床為實驗基礎(chǔ),對圓柱狀RDF顆粒的混合機(jī)制進(jìn)行了CFD-DEM數(shù)值模擬,驗證了計算結(jié)果與實驗結(jié)果的吻合性。然后自主設(shè)計并搭建了冷態(tài)隔板式內(nèi)循環(huán)流化床實驗臺,利用高速攝像機(jī)進(jìn)行了可視化觀測,重點討論了示蹤顆粒特性以及高低進(jìn)氣配風(fēng)比對于孔口處顆粒循環(huán)量的影響。最后進(jìn)行了相同工況下的CFD-DEM數(shù)值模擬,結(jié)果表明,合理的高低進(jìn)氣配風(fēng)比是實現(xiàn)顆粒內(nèi)循環(huán)混合的關(guān)鍵因素,同時指出雙組分顆�；旌隙葧S著孔口處顆粒循環(huán)量的增大而得到有效改善。內(nèi)循環(huán)流化床能夠進(jìn)一步改善床內(nèi)的物料混合狀態(tài),通過內(nèi)循環(huán)流化床進(jìn)行的實驗和數(shù)值模擬取得的研究成果,將對今后燃料顆粒在床內(nèi)混合提供實際應(yīng)用價值。
[Abstract]:The internal circulating fluidized bed has a unique advantage in the treatment of garbage derived fuel (RDF) combustion. The gas-solid two-phase flow characteristics in the bed directly affect the heat and mass transfer between phases and the chemical reaction rate. In this paper, the flow mechanism of single component particles and the mixing characteristics of two components particles in a cold partition type inner circulating fluidized bed are studied. The flow field and mixing of particles in the bed are simulated by the coupled discrete element method (CFD-DEM). The Euler method is used to deal with the continuous gas phase field and the Lagrangian method is used to directly track the single particle motion of the discrete particle field. The mixing mechanism in the inner circulating bed is studied from the multi-component particle level. In this paper, the mixing mechanism of cylindrical RDF particles is numerically simulated by CFD-DEM based on the 3D rectangular spouted fluidized bed established by Goldschmitt et al, and the agreement between the calculated results and the experimental results is verified. Then we design and build the cold partition type inner circulating fluidized bed test bed, and make visual observation with high speed camera. The characteristics of tracer particles and the effect of high and low intake air distribution ratio on the particle circulation at the orifice are discussed in detail. Finally, the numerical simulation of CFD-DEM under the same working condition is carried out. The results show that the reasonable ratio of high and low intake air distribution is the key factor to realize the cycle mixing in particles. At the same time, it is pointed out that the mixing degree of two-component particles will be improved effectively with the increase of particle circulation at the orifice. The internal circulating fluidized bed can further improve the material mixing state in the bed. The research results obtained through the experiment and numerical simulation of the inner circulating fluidized bed will provide practical application value for the future mixing of fuel particles in the bed.
【學(xué)位授予單位】：沈陽航空航天大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：X705

【相似文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 韋光超;流化床顆粒流動混合特性實驗與數(shù)值研究[D];沈陽航空航天大學(xué);2017年

，

本文編號：2100141