Sunday, March 21, 2021, 00:06
They have certainly seen that Silos decorate the agricultural landscape, ports, factories, etc., the very high number of accidents (explosions) with enormous human and economic losses is less known. Between 1900 and 1956, for example, they appeared in the US, in Granensilos, 1,120 explosions with 640 deaths and 1,700 injured. Due to the economic interest and, to prevent risks, science and technology have devoted a lot of attention from the start. Remember that Silos storage dressed materials of various nature and size: grains, sand, pelets, pills, stones, etc.
The construction of silos in the field, the railway stations and the Zeevoorten started in the second half of the nineteenth century, When grain crops started to have been abundant and their transport by rail and boat was generalized. The first designs were that the saved grain behaved like a normal liquid. Soon the silos, full of grain, became a laboratory for granular physics. For example, When the grain column in the silo is at rest, it behaves like a strange solid: the grain-hyone interaction breaks the symmetry imposed by gravity. This effect transfers the weight of the column to the side walls of the silo generation, for two reasons, important discomfort for the farmer. On the one hand, it prevents you from getting the weight of the grain that it saves and on the other hand the walls cannot support the normal force exerted by the grains on it. Let’s see what happens when the silo is downloaded by a hole (hole) in the background. In this case, the flowing grains behave like a special liquid. Even if the size of the holes greater than that of the grains, there is, for example, an interference effect that can interrupt the discharge. There are currently formulas that relate the speed of the grain exit current with the hole diameter during discharge. This current will be continuous if the diameter is larger than the so -called critical diameter, the spherical grain value of which is the diameter of a simple grain between four and five times. Moreover, the discharge speed is independent of the height of the grain column. This mysterious effect, which contrasts with what is happening with a liquid, is due to the fact that the grains are inelastic and what grain structures are called are formed.
We have seen some examples that justify the scientific interest that has aroused granular physics. If we add the economic importance of silos and hoppers, it is clear that the storage and discharge of silos have been strongly studied since the end of the 19th century. Today they continue to study because there are still problems without understanding and therefore solving. He Silo Design uses a lot of science and technology related to a ‘new science’: the physics of granular materials.
