Ultrasonic Intensity Detection and Cavitation Estimation in Biologic Engineering

Sonochemistry is widely used in material science and technology. Acoustic cavitation in the liquid medium is one of the most important factors of sonochemistry for biomaterial processing with ultrasound. It is well known that the degree of acoustic cavitation is determined with some physical parameters (such as ultrasonic intensity, wave type, vibration frequency and medium characters). Detection and control of the relative parameters are necessary for ultrasonic processing engineering. In the paper, the methods of detecting acoustic intensity are discussed and an intelligent method of estimating acoustic cavitation degree is introduced. The intensity detection system is made up of hydrophone, signal buffer, programmable amplifier, filter, amplitude demodulation, frequency detection, and temperature compensation circuits. The software for system management, control and digital signal processing is designed in assembly and C⁺⁺ language. Based on the hardware and software mentioned above, an intelligent system is set up. The advantage, stability and reliability of the system are proof-tested through debugging and application. It is proved that the measurement precision of acoustic intensity is better than plusmn3% in 10-100kHz. The performance is better than what of expectation.