A good understanding of the natural convective flow in hydrothermal autoclaves is essential
for the control of the growth rate and the quality of the grown crystals. This paper presents a
numerical simulation of turbulent natural convection in industry-size autoclaves with various
aspect ratios. A simplified 2D axisymmetric model was developed. Numerical results were
obtained for autoclaves with aspect ratios ranging from 2 to 20. Results show typical two
counter-flow cells in both the bottom and upper chambers. Heat conduction through the …