This paper presents a conjugate heat transfer model for industry size hydrothermal autoclaves. The electric heating on the wall outside surfaces is represented by constant heat fluxes. The circumferential heat flux deviation is introduced for the asymmetric factors from the surroundings. The results indicate that the temperature at the solution/wall interface is far from uniform. Circumferential temperature deviation is large enough to establish an asymmetric flow. To accurately simulate flows in industry autoclaves, one needs to use the conjugate model. The growth environment in current industry autoclaves, however, can be improved by establishing a uniform temperature on the wall/solution interface. (c) 2005 Elsevier Ltd. All rights reserved.