There are many bottom-blown smelting furnaces in metallurgical industry. When oxygen or air sprays from the jet nozzle into the bottom of the furnace, the melting phase will be frozen and a hemispherical porous zone w...There are many bottom-blown smelting furnaces in metallurgical industry. When oxygen or air sprays from the jet nozzle into the bottom of the furnace, the melting phase will be frozen and a hemispherical porous zone with a mushroom head shape will be formed around the nozzle. The mushroom head can pro- tect the jet nozzle and mitigate the liquid spray on the surface of melt. In order to analyze the formation process of a mushroom head in the bottom-blown smelting furnaces, a hydraulic experiment system was designed and the formation of the mushroom head was investigated by hydraulic experiment. The hydrau- lic experiment results show that the formation process is mainly divided into generating crushing genera- ting process and stable mushroom head generation process. The formation of stable mushroom head re- quires certain thermodynamic condition and water splash is more intense without a mushroom head than with a mushroom head. The size, porosity and diameter of the mushroom head are affected by the flow rate, temperature and heat capacity of the bottom-blowing gas and the temperature of the superheat and the physical parameters of the melt.展开更多
底栏栅式渠首是新疆粗颗粒山溪性河流引水防沙枢纽的首选类型,但实践运用表明,当引水量超过30 m 3/s时,渠首冲沙有利、工程布置紧凑的优势逐渐丧失,后期运行管理效益大打折扣。为此在保留原有布置优势的情况下,以扩大底栏栅引水流量为目...底栏栅式渠首是新疆粗颗粒山溪性河流引水防沙枢纽的首选类型,但实践运用表明,当引水量超过30 m 3/s时,渠首冲沙有利、工程布置紧凑的优势逐渐丧失,后期运行管理效益大打折扣。为此在保留原有布置优势的情况下,以扩大底栏栅引水流量为目标,提出了“⊥”型廊道新结构及优化布置方案,新结构在原垂直水流方向“—”型廊道结构基础上增设了顺水流方向“|”型廊道(根据流量的大小可布置双排甚至多排“|”型廊道),并结合底栏栅水流动力方程及取水流量计算方法得到了“⊥”型廊道取水流量的计算方法。随后以新疆头屯河渠首为例,在保持原平面布置不变的情况下引入“⊥”型廊道新结构,其引水量可达48.96 m 3/s,提升了39.89%,工程造价降低了63.46%。“⊥”型廊道新结构及布置方案突破了传统底栏栅式渠首设计引水流量相对较小的限制,拓宽了底栏栅式渠首的适用范围,还提高了经济效益,可为此类工程提供新的工程方案。展开更多
基金supported by the Fundamental Research Funds for the Central Universities(No.FRF-TP-15-022A3)
文摘There are many bottom-blown smelting furnaces in metallurgical industry. When oxygen or air sprays from the jet nozzle into the bottom of the furnace, the melting phase will be frozen and a hemispherical porous zone with a mushroom head shape will be formed around the nozzle. The mushroom head can pro- tect the jet nozzle and mitigate the liquid spray on the surface of melt. In order to analyze the formation process of a mushroom head in the bottom-blown smelting furnaces, a hydraulic experiment system was designed and the formation of the mushroom head was investigated by hydraulic experiment. The hydrau- lic experiment results show that the formation process is mainly divided into generating crushing genera- ting process and stable mushroom head generation process. The formation of stable mushroom head re- quires certain thermodynamic condition and water splash is more intense without a mushroom head than with a mushroom head. The size, porosity and diameter of the mushroom head are affected by the flow rate, temperature and heat capacity of the bottom-blowing gas and the temperature of the superheat and the physical parameters of the melt.
文摘底栏栅式渠首是新疆粗颗粒山溪性河流引水防沙枢纽的首选类型,但实践运用表明,当引水量超过30 m 3/s时,渠首冲沙有利、工程布置紧凑的优势逐渐丧失,后期运行管理效益大打折扣。为此在保留原有布置优势的情况下,以扩大底栏栅引水流量为目标,提出了“⊥”型廊道新结构及优化布置方案,新结构在原垂直水流方向“—”型廊道结构基础上增设了顺水流方向“|”型廊道(根据流量的大小可布置双排甚至多排“|”型廊道),并结合底栏栅水流动力方程及取水流量计算方法得到了“⊥”型廊道取水流量的计算方法。随后以新疆头屯河渠首为例,在保持原平面布置不变的情况下引入“⊥”型廊道新结构,其引水量可达48.96 m 3/s,提升了39.89%,工程造价降低了63.46%。“⊥”型廊道新结构及布置方案突破了传统底栏栅式渠首设计引水流量相对较小的限制,拓宽了底栏栅式渠首的适用范围,还提高了经济效益,可为此类工程提供新的工程方案。
