The effect of sweat on the performance of the interface between skin and flexible membrane

Upon realizing the importance of the sweat in controlling the performance of the interface crack between skin and flexible membrane, the effect of sweat on the crack opening under action of the far-field tensile stress is analysed in present paper. Application of the complex variable method and the principle of superposition gives the crack opening displacement and the stress intensity factors, which are functions of the surface tension, contact angle, location and size of the sweat. The location of sweat has important influence on the stress intensity factors, although it induces very little changes in the shape of the crack opening. Without or with the action of a small far-filed tensile stress, the sweat can induce the crack partial closure. With the increase of the far-field tensile stress, the crack opening displacement will be large enough to cause the disruption of the sweat, even induce the crack growth. So, the far-field tensile stress, which can split the sweat, is derived in present paper.