Abstract A novel rotational hydrodynamic cavitation device (called WLAC, composed of rotor and stator) was designed for treatment of wastewater, as well as two other structures with different lead angle based on WLAC, namely, LLAC and HLAC. The velocity characteristics, cavitation number, cavitation bubbles distribution, and production capacity of the hydrodynamic cavitation device were analyzed. Experimental results showed that the concentration of ·OH increased with treatment capacity as the water was decomposed into ·OH and ·H due to cavitation, which indicated the feasibility of the designed cavitation. The high velocity was mainly distributed around movable teeth and decreased to both sides in WLAC but was distributed between the groove of fixed teeth in LLAC and HLAC, as well as the cavitation region. Meanwhile, the cavitation intensities of HLAC and LLAC were significantly higher than WLAC; especially, the cavitation bubbles generated by HLAC were 54% higher than those generated by WLAC. In addition, the production capacity of hydrodynamic cavitation device decreased with the increase of Re. Due to the stronger capability of cavitation cloud generation and suppression of short circuit flow, the HLAC had higher production capacity of cavitation. The results presented here may provide a workable reference regarding the cavitation generation mode on higher cavitation performance and production capacity for wastewater treatment.
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