Motion characteristics and residence time of particles in the new cross structure under constant-pulse condition

Abstract

The residence time of particles in the flow field is highly sensitive to the fluid’s flow characteristics and the particles’ motion. We proposed a dynamic entry mode with the constant-pulse (CP) condition in response to the conditions of symmetric impinging streams and asymmetric impinging streams. Single-particle motion behaviors and particle residence time in a novel cross-type structure reactor we designed were studied and discussed in this article. This was done by looking at how these variables changed depending on the impulse inlet velocity conditions, the reactor geometry, and the particle properties. The results demonstrate that when particle relaxation time is short, those particles without oscillatory motions were directly accelerated to leave the active area. When its relaxation time is reasonably set, even a single particle can hugely elevate the oscillatory motions. With the structure of the novel cross type, the particle merely exhibits three oscillatory under the condition of the symmetric pulse inlet flow and asymmetric pulse inlet flow, notwithstanding, CP contains at least three oscillatory motions. The t_tot is the duration that an individual particle spends in the working region. The t_tot and active area were affected by inlet velocity, parameters of particles and the shape of the reactor parameters of particles and the shape of the reactor. The t_tot raised with τ* increased in a certain range. T is the inlet velocity variation period. The particle resides time at T = T_b reaches a maximum in the CP. The maximum residence times T_b was affected by particle relaxation time, under CP with a diameter ratio of 5 and inlet velocity difference of 0.8. The particle retention time in the novel cross-type structure reactor was heightened by 7 times. The CP and the novel cross-type structure reactor can improve the retention time of particles in the flow field.

Keywords:

• CFD
• constant-pulse condition
• particle motion
• residence time
• turbulent agglomeration

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This research was supported by Natural Science Foundation of Liaoning Province (2022-MS-461), China Postdoctoral Science Foundation (2020M672084), Liaoning Key Laboratory of Chemical Additive Synthesis and Separation (ZJKF2005), Natural Science Foundation of Panjin (202101018), LiaoNing Revitalization Talents Program (XLYC 2203159).