Salicylic acid can ease the dynamic activity of cavitation. Furthermore, it is possible to measure dynamic activity trough the products of OH radical reactions with salicylic acid. With radicals forming when cavitation bubbles implode, releasing big amounts of energy. In the experiment we were changing the concentration of salicylic acid and air in the solution. An apparatus was assembled that pumped distilled water through the Venturi nozzle, where cavitation formed in the constricted area. This was also the part of the nozzle that was filmed with a fast camera. With a program in Matlab we processed the images taken with the camera to make pictures of cavitation average location and standard deviation. From these pictures it was easier to distinguish in which solutions the dynamic activity was higher. In the second part of the experiment we analyzed the samples of salicylic acid with HPLC method to determine the concentrations of 2,3-DHBA, 2,5-DHBA and catechol as they were the products of salicylic acid reacting with OH radical. We wanted to see if there is a correlation between the amounts of products that were yielded with the dynamic activity seen on the pictures made in Matlab. It was noticed that high dynamic activity on pictures did not lead to more products. Radicals could have rearranged before salicylic acid had the chance to trap them. Also higher concentration of salicylic acid didn't always yield more products. In the visualization part it was also noted that most dynamical active pictures were actually those with higher salicylic acid concentrations, which wasn't the case in some of previous similar experiments.
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