Flow simulation and experimental study of a dynamic asymmetric impinging stream

Abstract

Classical impinging stream technology can effectively enhance heat and mass transfer and is widely used in various chemical fields. The energy of a particle is rapidly reduced after penetrating the reverse jet due to the fluid resistance in a steady symmetrical impinging stream reactor; thus, the effective particle motion range is restricted. In this paper, we propose a new dynamic asymmetrical impinging stream reactor with dynamic sinusoidal variation in the inlet velocity. We investigated the flow field structure and characteristics of the dynamic asymmetric impinging stream reactor based on numerical simulation and experimental verification. The impingement surface was instantaneously moving in the axial region of the impinging stream reactor, thereby increasing the range of motion of the main active area. In this paper, we discuss the axial turbulent kinetic energy distribution and single particle motion behavior in the context of a dynamic asymmetrical impinging stream with an instantaneously moving impinging surface. In the simulation, the maximum turbulence kinetic energy was still located in the impingement region in the dynamic asymmetric impinging stream reactor (in agreement with that of the steady symmetric impinging stream technology), and the position variation in the maximum turbulent kinetic energy was consistent with that of the impinging surface. In addition, the notable improvements in the particle residence time and motion distance in the main active area have obvious practical advantages in engineering compared with using steady symmetrical impinging stream technology.

Additional information

Funding

This work is supported by the National Natural Science Foundation of China [Grant No. 51506072 and 51375183] and the National Basic Research Program of China (Project No. 2015CB251504).