Meaning of Capillarity
In order to understand the meaning of the term capillarity, it is necessary, first of all, to discover its etymological origin. In this case we can say that it is a word that comes from Latin and is the result of the sum of three components of that language:
-The noun “capilus”, which can be translated as “hair”.
-The suffix “-aris”, which is equivalent to “relative to”.
-The suffix “-dad”, which is used to indicate “quality”.
According to DigoPaul, capillarity is called the phenomenon that makes the surface of a fluid, when in contact with a solid body, rise or fall according to whether or not the element in question is wetted.
The concept derives from capillary, which in one of its meanings refers to a very fine conduit. It is also said that a phenomenon is capillary when it occurs by capillarity.
It can be stated that this property is dependent on the surface tension of the liquid, which makes the liquid face resistance when increasing its surface. The surface tension, in turn, is linked to the cohesion of the fluid.
According to the surface tension, the liquid may descend or rise through the capillary tube. This phenomenon is what we know as capillarity.
When the cohesion between the molecules is less than the adhesion of the fluid to the tube, the liquid wets and, therefore, moves up the conduit. This rise will continue until the surface tension balances as a consequence of the weight of the fluid.
On the other hand, if the molecular cohesion of the fluid is greater than the adhesion to the tube, the surface tension causes a decrease in the liquid.
Capillarity makes the water, in a capillary tube, rise. This is why plants can absorb groundwater. The phenomenon, on the contrary, causes the mercury to descend in a glass duct.
The curve that is generated on the surface of a fluid as a reaction to the surface of the container is called the meniscus. The meniscus is concave when the molecules in the fluid and those in the tube attract each other (as in the case of water in a glass container) and convex if the opposite occurs (mercury in a glass tube).
Capillarity is also a very common term used in the construction sector. Thus, it is used to refer to a specific problem that can appear in buildings and homes. We are referring to the so-called capillary humidity.
This problem occurs because the water that exists in the land on which the construction has been carried out is a lot and that brings with it that it evaporates in the areas that perspire and that it gradually becomes present on ceilings and walls. The usual thing is that it is shown by means of dark colored spots, with dampness in what would be the so-called baseboards and even with bulging of the paint. All these manifestations that, to a greater or lesser extent, spoil the image of the home or the premises itself.
In order to put an end to this problem of capillarity and humidity, what will remain is to carry out an exhaustive analysis of the construction to be able to know the causes and take the appropriate measures. Among those alternatives would be to undertake a good insulation by waterproofing the affected walls and ceilings.