I recently asked a question on a canvas water bag and I realized that there was something really interesting that I didn’t understand. When a dry water bag gets filled, it leaks a lot of water; however, after sometime the water stops leaking and some of the water seeps and is cooled by evaporative cooling.
My question here is that in order for the water to stop leaking, the canvas fibers must “expand” to stop the water. It can’t be a linear or thermal expansion since this is occurring at the same temperature. Is it the unfolding of canvas fibers or something else? That is, what type of expansion occurs in a water bag to stop it from leaking?
Furthermore, is this the same process that occurs when doors swell during the rainy part of the year? That is, why do doors swell when they get wet?