Sonochemical Reactor Acoustic Field Of Research

Sonochemical reaction is a new interdisciplinary that developed in the1980s. Sonochemical reaction can increase the rate of chemical reaction and shorten the reaction time, improve the reaction selectivity. And can stimulate a specific chemical reaction only in the presence of ultrasonic. It is widely attracted due to unique response characteristics and is one of important research areas in synthetic chemistry. The main mechanism of the sonochemical reaction is the cavitation generated by ultrasonic wave in liquid, and because of the change of the reaction conditions caused by cavitation. it results the thermodynamic change in the chemical reaction, and improves the chemical reaction rate and productivity. But the cavitation is an extremely complex nonlinear dynamic process, there is not thoroughly research for it so far. At present it is still a hot topic in nonlinear acoustics. However, the cavitation sound field is extremely important in the sonochemical reactor both in the entire response system and the reaction effect. Therefore, it is significant to research the Influence factors of cavitation sound field in sonochemical reactor. Considering the reactor wall, the transducer device lineup, the reaction liquid height, we researched on the sound field characteristics affect the reactor.This paper duces theoretically and simulates the directivity of a circular piston sound source located in the bottom of the reactor in the form of matrix. Using the laboratory sonochemical reactors as the research objects, from the numerical simulation and experimental two aspects, researches the space dire ctional characteristics of the matrix circular piston specifically Specific work and conclusion as follows:(1) It deduced the sound pressure and directivity function of matrix circular piston combination of sound sources in space at any point theoretically, and used matlab software to map out the sound field of three-dimensional point function image with different values of ka and transducer numbers in high-frequency (ka>1) and low-frequency (ka<1) caseand compared the directionality images of high frequency and low frequency. The results show that the higher radiation frequency of the sound source and the more number of transducers, the stronger directivity and the higher concentration of sound energy.(2) Taking the rectangular sonochemical reactors as the research objects, using Ansys finite element software to simulate its internal sound pressure amplitude distribution. It showes that the sound field strength and uniformity of rigid tank wall is better than the slot wall with the transducer do forced vibration, The main reason is that the bending vibration incident wave of the slot wall is absorbed by the wall, converts into heat, makes the groove wall around less acoustic energy; The more number of transducer device, the better the sound field intensity and uniformity.(3) Taking One-dimensional acoustic wave equation as the theoretical basis and combining with acoustic boundary conditions, we deduced the sound pressure distribution in the vertical direction when the circular piston transducer paste at the bottom of the reactorThe results show that pressure into a standing wave mode distribution in vertical direction.(4) Numerical simulation the sound pressure amplitude distribution of different liquid level in a cylindrical sonochemical reactor. Compared the liquid surface height effect on the acoustic field distribution within reactor, and with aluminum foil corrosion method measuring the sound field distribution in the diverse liquid level, found the simulation results are same with the experimental results. Results show that when the reactor size and number of transducers had a certain value, the liquid surface height would get a best value, at this time the sound field intensity and uniformity to the best.