循环流化床内气粒两相传热的萘升华模拟实验研究

The Experimental Study of Gas-Particle Inter-Phase Heat Transfer in Circulating Fluidized Beds Using Naphthalene Sublimation Technique

在循环流化床试验台上对床中气体与颗粒两相间的传热特性进行了试验研究,试验中首次将萘升华热质类比技术应用于循环流化床内气粒两相间传热的研究中,考察了不同的固体颗粒循环量、一次风风速和床料平均粒径对气粒间换热的影响。试验表明:随着一次风风速的增加,循环床中气体和颗粒之间的表现热换系数变大,当固体颗粒循环量增加或颗粒平均粒径减小时,表征相间换热特性的Nu数增大。

The gas-particle inter-phase heat transfer characteristics was investigated in a circulating fluidized bed experimental set-up. The naphthalene sublimation technique was used to study gas-particle inter-phase heat transfer in circulating fluidized beds for the first time. The experiment investigated how the particle circulation rate, primary airflow and praticle size affect the heat transfer between gas and particles in circulating fluidized beds. The results showed that the apparent convective heat transfer coefficient would become larger when the primary airflow increased, and the Nusselt number would get larger while the particle circulation rate increased or the average particle diameter decreased. Figs 5, table 1 and refs 4.