Phase coexistence in fluidization
Feng Lu, Chenxi Zhang, Yao Wang, Weizhong Qian, Fei Wei
Abstract
Abstract The coexistence and interaction of a granular liquid‐like phase (emulsion) and a gas‐like phase (bubbles) in fluidization is a spontaneous symmetry‐breaking dissipative state, contributing to excellent mixing behavior in fluidized beds. In the present study, a universal granular state equation to describe the phase coexistence at far away from the critical point is developed by taking both the inelastic solid collision and asymmetrical instability into consideration. Besides, a cold‐flow experiment using particles of the Geldart's A group at 0.1–1 MPa pressure is performed to verify the granular state equation, where the solid volume fraction ( ε s ) and solid pressure ( p s ) are obtained by a dual optical probe and a special pressure transducer, respectively. Based on both theoretical analysis and experimental study, a phase diagram is produced to serve as a useful guide for the design and operation of efficient fluidized‐bed reactors.