The teeter bed zone is the critical component of the teetered bed separator (TBS), and the calculation of its height plays an important role in optimizing structure of TBS and improving separation performance of coarse slime. This paper simulates the velocity profile in TBS using jet theory and discusses the relationships between velocity profile and axial height as well as fractional open area. The separation of 2-0.3 mm coals using TBS with different bed lengths was also performed. The simulation results show that flowing behavior in the teeter bed zone through the distributor could be simplified as single round hole jet in con-current ambient; the fractional open area and axial height of TBS are two important influencing factors, and the even velocity distribution could be easily achieved with greater axial length and larger fractional open area. The height of the teeter bed zone could be calculated using H-tb = exp(1.0164-phi/0.2089) x d(0), showing that the teeter bed height increases with an increase in hole diameter and a decrease in fractional open area. The experimental results show that good performance with Ep value of 0.117 is achieved using the TBS with bed length of 1000 mm, due to the even velocity distribution with minimum flow disturbance resulted from the use of larger bed length. (C) 2016 Elsevier B.V. All rights reserved.