中文摘要：

氮化镓晶体是继单晶硅之后的一种新型的半导体材料。本文利用有限体积法模拟了氨热法生长氮化镓晶体中流场的瞬态特性,研究了隔板开孔10%时流场结构、温度场、浓度场。发现对于隔板开孔率（10%）的情形,中心开孔及边缘间隙的平均速度表现为振荡的特性,中心开孔速度大多是正的,边缘开孔大多是负的。大的温度梯度发生在在高压釜壁面与液体的交界处与隔板周围。物质由多孔介质区向生长区输运。

英文摘要：

Gallium nitride（GaN） crystal is a new semiconductor material after silicon single crystal. This paper has simulated the transient characteristic of flow field in an autoclave using the finite volume method,we analyzed the flow field,temperature field and concentration field with a baffle opening of 10%.In the case of baffle opening of 10%,the mean flow velocities in the center hole and ring gap have the oscillation behavior.The velocities in the center hole are almost positive while those in ring gap are almost negative.Large temperature gradients exist at the the fluid/autoclave interface and baffle.