化工进展
化工進展
화공진전
CHEMICAL INDUSTRY AND ENGINEERING PROGRESS
2014年
2期
328-332
,共5页
锥形流化床%水平射流%最小流化速度%最大压降
錐形流化床%水平射流%最小流化速度%最大壓降
추형류화상%수평사류%최소류화속도%최대압강
conical fluidized bed%horizontal jet%minimum fluidization velocity%maximum pressure drop
在一个160 mm×300(20) mm×30 mm(高×宽×厚)、锥角为60°的二维锥形流化床中研究了两侧水平射流条件对3种不同粒径颗粒流化特性的影响。临界流化曲线结果表明:压降随着流量增大而迅速升高,到达一个最大值后略有下降。另一方面通过实验观察,提出“沸腾核心”假设,并推导出颗粒达到起始流化状态时,流速沿床层高度的变化规律。在假设的基础上,根据厄贡方程推导得出最大压降的计算式,计算结果表明计算值略大于实验值。另外,实验中还发现二维锥形流化床的最小流化速度随颗粒粒径增大而增大,随填料体积的增大也略有增大。
在一箇160 mm×300(20) mm×30 mm(高×寬×厚)、錐角為60°的二維錐形流化床中研究瞭兩側水平射流條件對3種不同粒徑顆粒流化特性的影響。臨界流化麯線結果錶明:壓降隨著流量增大而迅速升高,到達一箇最大值後略有下降。另一方麵通過實驗觀察,提齣“沸騰覈心”假設,併推導齣顆粒達到起始流化狀態時,流速沿床層高度的變化規律。在假設的基礎上,根據阨貢方程推導得齣最大壓降的計算式,計算結果錶明計算值略大于實驗值。另外,實驗中還髮現二維錐形流化床的最小流化速度隨顆粒粒徑增大而增大,隨填料體積的增大也略有增大。
재일개160 mm×300(20) mm×30 mm(고×관×후)、추각위60°적이유추형류화상중연구료량측수평사류조건대3충불동립경과립류화특성적영향。림계류화곡선결과표명:압강수착류량증대이신속승고,도체일개최대치후략유하강。령일방면통과실험관찰,제출“비등핵심”가설,병추도출과립체도기시류화상태시,류속연상층고도적변화규률。재가설적기출상,근거액공방정추도득출최대압강적계산식,계산결과표명계산치략대우실험치。령외,실험중환발현이유추형류화상적최소류화속도수과립립경증대이증대,수전료체적적증대야략유증대。
The influences of two sides horizontal jet on the fluidization characteristics of three different-sized particles were studied by using a two-dimensional conical fluidized bed with the size of 160 mm × 300(20) mm× 30 mm (height × width × thickness) and cone angle of 60°. The critical fluidization curve showed that pressure drop increased rapidly with increasing flow rate and decreased slightly after reaching a maximum. On the other hand,the hypothesis of“boiling core”was proposed based on experimental observations,and the change of flow rate with variation of bed height when the particles reached an incipient fluidization state was deducted. Based on the hypothesis,the calculation equation of maximum voltage drop was deducted according to the Ergun equation,and the calculation results showed that the calculated values were slightly higher than the experimental values. In addition,the minimum fluidization velocity of the two-dimensional conical fluidized bed increased with increasing particle size,but increased slightly with increasing filler volume.