Washing machines are one of most common devices on the globe. At the same time, washing machines are big energy and water consumers. In this doctoral thesis, we investigate potential to improve washing machine performance using cavitation. Cavitation is due to extreme conditions that occur at bubble collapses, generally perceived as harmful phenomena. However, when generated under controlled conditions, cavitation can intensify energy-intensive processes. Similarly, we could harness cavitation to improve the efficiency of washing machines. For this purpose, we designed a special rotary generator of hydrodynamic cavitation. The following effects of cavitation have been studied experimentally: influence of cavitation on the detergent dissolution kinetics and its mechanism; influence on the degradation of the sodium dodecylbenzenesulfonate, the most important component of laundry detergents, and the influence of wash bath preparation with cavitation on the washing performance. The results show that the cavitation intensifies the detergent dissolution with a mechanism similar to the cavitation erosion. Cavitation causes detergent degradation, but the amount is so small that it should not affect the laundry process. Finally, we confirm that using cavitation enhances stain removal. This could lead to considerable reduction of time required for laundry.
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