热羽流与置换通风作用下油雾颗粒预测模型
Prediction model of oil mist particles under the effects of heat plume and displacement ventilation
王非 1孟钦鹏 1翁文兵 1耿宇 1王昕1
作者信息
- 1. 上海理工大学环境与建筑学院,上海 200093
- 折叠
摘要
高大空间机械厂房采用置换通风系统时,存在竖直方向油雾颗粒浓度分布不均匀的现象.这种现象会影响以降低室内颗粒浓度为目的的需求通风量.为了快速预测竖向油雾颗粒浓度分布,采用区域模型建模方法,考虑壁面流区、热羽流区和主流区等主要区域,基于质量平衡与能量平衡方程,建立了竖向油雾颗粒浓度分布预测模型;同时在实验舱内进行了实验验证,模型计算结果与实验结果趋势相符,最大相对误差不大于 20%,表明该模型能够基本满足工程要求;以 5 种颗粒散发率工况为例进行节能分析,发现引入预测模型后计算得到的置换通风系统需求通风量可比传统变风量系统通风设计方法计算的减少 18.83%～44.41%.该预测模型能较为准确地预测高大厂房中置换通风时竖向不同高度的油雾颗粒浓度,可应用于需要快速预测竖向颗粒平均浓度的场景.
Abstract
The vertical inhomogeneous particle concentration in a large-space machining workshop with a displacement ventilation system will increase the required ventilation volume for indoor particle concentration reduction.The present work presents a particle concentration prediction model using a zonal modeling method that can rapidly predict the vertical particle concentration distribution for the energy-saving performance analysis of the ventilation system.The model,which takes the wall heat plume zone,heat source heat plume zone,and main airflow zone into account,can obtain the inter-regional airflow based on the energy balance and continuity equations and predict the zonal particle concentration based on the mass balance equations using particle emission rates and inter-regional airflow.A validation experiment conducted in a scaled chamber demonstrates that the relative error of the prediction model is less than 20%,it shows that the model can basically meet the engineering requirements.Further study of the prediction model by a case study under five particle emission conditions showed that the required air volume supply can be reduced by 18.83%to 44.41%compared to the traditional method used on variable air volume system.Overall,the prediction model can accurately and rapidly predict the vertical particle concentration distribution in large-space machining workshops under displacement ventilation,showing promising prospects in optimizing the performance of the ventilation system.
关键词
机械加工/油雾颗粒/垂直分布/区域模型/热羽流Key words
machining/oil mist particles/vertical distribution/zone model/thermal plume引用本文复制引用
基金项目
国家自然科学基金面上项目(52278116)
机械工业联合会重点实验室创新平台项目(2019SA-10-07)
出版年
2024
国家科技期刊平台
NSTL
万方数据