摘要
为优化纸机干燥部气罩气流参数和零位控制系统,在对密闭气罩内外空气条件测量的基础上,分析了机械通风情况下气罩内外压差变化曲线,量化分析了气罩内空气温度和进排风量差变化对零位高度的影响,建立了零位控制量化模型。结果表明:上层气罩内空气温度变化幅度约为进风温度变化幅度的55%,罩内温度与零位高度成反比关系;进风湿度变化引起进排风量差的变化值约为12.5%,进排风量差与零位高度成正比关系;零位高度的偏离可通过设置前馈控制系统、调节进排风量差来进行补偿和调整。
In order to optimize airflow parameters and zero-position control system of the closed steam hood in paper machine’s dryer section, the air condition both inside and outside of the hood was firstly analyzed. The pressure-difference changing curve between inside and outside of the hood was established under mechanical ventilation. On the other hand, the influence of air temperature or volume-difference between supplied and drawn air on zero-position was also quantitatively analyzed. Finally, the quantificational zero-position control model was established. The results indicated that the air temperature inside upper hood, the variation of which is about 55 % of the variation of supplied air temperature, is directly propotional to the level of zero-position. The variation of supplied air moisture can cause the volume-difference between supplied and drawn air changing by about 12.5 % which has an inverse propotion to the level of zero-position. According to the principle of adjusting the volume-difference between supplied and drawn air, the deviation of zero-position can be quickly regulated by setting feed-forward control system.
出处
《南京林业大学学报（自然科学版）》
CAS
CSCD
北大核心
2010年第2期95-100,共6页
Journal of Nanjing Forestry University：Natural Sciences Edition
基金
南京林业大学江苏省制浆造纸科学与技术重点实验室开放基金项目(200812)
关键词
造纸机
干燥部
气罩
压差曲线
零位控制
量化模型
paper machine
dryer section
steam hood
pressure-difference curve
zero-position control
quantificational model
