Method and device for detecting air tightness of waterproof breathable film based on variable dielectric constant

The invention discloses a waterproof breathable film airtightness detection method and device based on a variable dielectric constant, and the method comprises the following steps: S1, placing a waterproof breathable film in a test region, and enabling the test region to be divided into a first region and a second region; s2, a water outlet is formed in the second area, and a pair of parallel capacitor plates are arranged outside the second area and located on the two sides of the water outlet; s3, water is introduced into the first area, after the waterproof breathable film is fully covered with the water, the first area is filled with air pressure needing to be tested, and then measurement is started; s4, monitoring a capacitance value between the parallel capacitor plates, and if the capacitance value is increased, determining that the waterproof breathable film leaks; if the capacitance value is not changed, leakage does not occur; and S5, after the test is finished, drying the test area, and then carryin