Sanchez B., Llado J., Garcia J., Pina C., Monterde F.

Induction cooktops have many advantages over other cooking appliance methods, including efficiency, controllability, and safety, but as drawback their sound power level is the highest, and this reason could be a deciding factor in the purchase of other conventional cooktops. Nowadays, it does not exist a standard procedure to evaluate the sound power level of an induction cooktop. Therefore, this work has been focused on analyzing the time evolution of the sound pressure emitted by an induction hob, to determine the most significant periods, and to define the way of measurement. At a semi-anechoic room, the tests were performed with two types of pots filled with 2 liters of water, and placed on the bigger cooking zone. During the heating of the water at maximum power, the sound pressure level was recorded with the microphone at position one according to the international standard ISO 3744. It was found that the evolution of this parameter not only depends on the induction cooktop but also on the type of cookware, being the enameled pots more silent than the stainless steel pots with sandwich bottom. Once the sound pressure level was characterized, the next step was to evaluate the sound power emitted by both elements. The sound intensity emitted by the cooktop and the pot, was measured with an intensity probe according to ISO 9614, and it was determined that the sound power was similar for both elements. In base to these results, it is necessary to improve the design of both elements from an acoustical point of view. The future work proposed is the identification of the noise sources of the cooktop in order to know which component is the responsible for its sound emission, and the theoretical analysis of different types of pots by means of noise prediction software.