摘要
多孔材料在电厂高温余热回收领域具有广泛的应用,对其内部流动和传热特性的研究对于提高能量利用率,降低环境污染,实现“双碳”目标具有重要意义。通过仿真模拟的方法研究了模拟烟气、水蒸气及含尘烟气三类高温流体在多孔氧化铝陶瓷材料内的流动及传热特性。结果表明:随孔隙率增大,流体平均流速加快,流体进出口温降减小。三类流体中,水蒸气流速最大,在最大孔隙率下其流速达到66.64 m/s;烟气温降最显著,当孔隙率为0.3时,其进出口温差达到最大值85.6 K。随压差增大,流体流速加快,其中受粉煤灰颗粒影响的含尘烟气流速增幅较小,流速仅从0.23 m/s增至0.93 m/s;另一方面,压差增大导致流体与壁面的热传导减少,模型内流体温降减小。含尘烟气流体扰动较大,当增大孔隙率和压差时,流速呈线性增长;粉煤灰颗粒的存在使含尘烟气的温度在分子相互作用下发生显著变化。
Porous materials are widely adopted in the recovery of high temperature waste heat in power plants.The research on the internal flow and heat transfer is of great significance for the improvement of energy utilization,environmental pollution reduction and realization of“carbon peaking and carbon neutrality”.The characteristics of flow and heat transfer of simulated flue gas,water vapor and dust-laden flue gas in porous alumina ceramic materials were studied by means of simulation.The results show that the average fluid velocity increases,while the fluid temperature difference between the inlet and outlet decreases with the enlargement of materials porosity.Among these fluids,the velocity of water vapor is the largest which reaches 66.64 m/s at the maximum porosity,the temperature drop of flue gas between the inlet and outlet is the most significant which is 85.6 K when the porosity is 0.3.The fluid flow rates increase the rising of pressure differences,and the flow rate of the dust-laden flue gas is slightly affected by the increase of fly ash particles which is from 0.23 m/s to 0.93 m/s.The heat conduction between the fluid and the wall is weakened due to the increase of velocity,and the temperature drop of the fluid is also reduced.The fluid disturbance of dust-laden flue gas is relatively larger,and the flow velocity increases proportionally with porosity and pressure difference.While,the molecular interaction makes the temperature of dust-laden flue gas changes significantly besides the presence of fly ash particles.
作者
井冲霄
李景明
严彬彬
JING Chong-xiao;LI Jing-ming;YAN Bin-bin(College of New Energy,Xi'an Shiyou University,Xi'an 710065,China)
出处
《科学技术与工程》
北大核心
2023年第15期6542-6548,共7页
Science Technology and Engineering
基金
国家自然科学基金联合基金(U20B2036)
陕西省自然科学基础研究计划(2020JM-541)
西安石油大学研究生创新与实践能力培养计划(YCS21112069)。
关键词
多孔陶瓷
高温流体
孔隙率
压差
porous ceramics
high temperature fluid
porosity
pressure difference
