Abstract
<jats:p>Research on automobile whistling and suction sounds has been conducted in the past. For cavity resonance, a type of whistling sound, the cavity resonance frequency has been determined using Rossiter's empirical formula. Therefore, we limited our study to the two-dimensional case and clarified the physical phenomena that arise by solving a set of partial differential equations that explain the phenomenon. As a result, we found that the horizontal resonance frequency becomes proportional to the speed of sound as the mainstream velocity increases, and the vertical resonance frequency decreases as the mainstream velocity increases, but when the Mach number exceeds 1, the resonance frequency no longer exists as a real number, and vertical resonance does not occur. Finally, we discussed the conditions under which resonance increases. Finally, we were able to confirm the conditions under which resonance increases through numerical calculations.</jats:p>