Fluid Flows in an Industry Hydrothermal Autoclave with Seed Crystals and Raw Lascas

Abstract

The fluid flows in hydrothermal growth vessels have significant effects on growth quality. This article presents a numerical investigation on the fluid flow and heat transfer in an industry hydrothermal autoclave. The focus is on the modeling of the seed crystals in the growth chamber, the raw lascas in the dissolving chamber, and their effects on the turbulent flows. The fluid and heat transport processes in the autoclave at representative stages of a growth run are simulated. Results show that the growth chamber has one flow cell at the beginning and another flow cell is developed later in a growth run. The dissolving chamber has a cell flow in the fluid region. A wall layer and core flow structure is established in the raw material region which carries significant heat transfer resistance. The transport through the baffle opening is between two flow cells. The fluid transport processes varies, and the thermal environment in the growth chamber changes significantly as the raw material bed is dissolved and the seed crystals grow.

Notes

The middle of a growth run (φ _S  = 0.683, φ _R  = 0.40, and H _R /D = 2.5).