In this talk, Prof. Chen will examine the role of increased inner-core diabatic cooling in TC SEF and ERC by using idealized numerical simulation in WRF. The experiment with the low-level inner-core diabatic cooling increased is characterized by the low-entropy air and downward motion in the inner-core region whereas the convergence and active convective updrafts in the outer-core region. In collaboration with the favorable dynamic ambient conditions and unbalanced boundary layer dynamics induced by the outer rainbands, the concentric convective ring is triggered and contracts inward to replace the inner eyewall, and the deep-tropospheric radial outflows driven by the strong outward-directed agradient force give rise to a largely outward-tilted eyewall then, eventually forming a large-eyed storm. The sensitivity of SEF and ERC to the strength and radial location of low-level cooling is further investigated.