A 72-hour numerical simulation of Typhoon Damrey is performed by using WRF (V3. 1. 1). The possible mechanism resulted in the rapid intensification is explored. The results show that: (1) Interaction between easterly waves and typhoon's circulation at upper-levels during the slowly intensify stage induced a broad range of northeast-southwest direction outflow channel, which increased divergence at upper-levels and was favorable to the intensification; the vertical wind shear reduced in the first 12 hours, and the rapid intensification lagged behind the vertical wind shear decrease. (2) The water vapor flux toward the typhoon's center at lower-levels increased magnificently during the rapid intensify stage; the heat flux, latent heat flux and moisture flux, at the sea surface were growing constantly, and the contribution of latent heat flux was greater than that of heat flux. (3) The mechanism of conditional symmtrical instability excited the tilted updraft; the development of slantwise vorticity induced the significant increment ofrnrelative vorticity near the typhoon center and promoted the strengthening process.%利用WRF模式(V3.1.1)对0518号台风“达维”(Damrey)进行了72 h的数值模拟.重点分析了影响台风强度迅速加强的可能机制,结果表明:①缓慢加强阶段,东风波与台风高层环流相互作用形成一条东北一西南走向的外流通道,加强台风高层辐散流出,有利于台风强度加强；垂直风切变在积分前12 h减小,台风迅速加强与垂直风切变减小间存在滞后性.②迅速加强阶段,低层指向台风中心的水汽通量大大增加；海表面热通量、潜热通量和水汽通量持续增强,海表面潜热通量对台风的能量贡献远大于热通量.③台风眼壁附近的条件性对称不稳定机制激发斜升气流,倾斜涡度发展引起中心附近相对涡度增大,台风整体强度得到加强.
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