A new shell structure of converged-diverged tube bundle supported by twisted-leaves in shell-and-tube exchanger is proposed.The characteristics of heat transfer and flow resistance of converged-diverged tube bundle supported by four types of twisted-leaves and ring respectively for air turbulent flow in the longitudinal direction were investigated experimentally and compared with each other.The results indicated that the compound heat transfer enhancement of the converged-diverged tube bundle supported by 270-20.3 or 180-20.3 twisted-leaves was obvious.Especially for 270-20.3

the heat transfer enhancement valuation factor was higher than that of converged-diverged tube bundle supported by ring by 18% when Reynolds number was in the range from 2000 to 20000 for air turbulent flow.