Diseño y construcción de un generador de hielo en bloque para el laboratorio de refrigeración.

Abstract

In this thesis the process of design, construction and testing of a block ice machine is detailed in order to develop laboratory practices, and calculate the speed of water cooling and ice formation speed. The system control is performed by a temperature controller to maintain the brine solution within the established range; a level sensor to avoid spills and a temperature sensor for the end of ice formation. A matrix with 12 sensors in all three directions was made for data acquisition led by an Arduino. The equipment capacity is 10 kg, distributed in two molds of 5 kg each one. The tests were conducted with softened water and normal water (from the tap) at different temperatures from brine solution. The tests were conducted repeatedly obtaining different data, but similar curves, where zones with characteristics very different from each other can be noticed. That is why three zones were found in the normal water cooling, and two zones with softened water. In the ice formation as well as with normal water as with softened water, its behavior determines four zones, which are mentioned as: cooling phase, change of state phase, sub cooling phase and balance phase; in each one of them varying the process speeds. The normal water cooling related to the softened water is 30% faster, existing in both cases a fast cooling that lasts around 10 minutes, with an average speed of 1,379 °C/min ± 10%. In the ice formation can be noticed that from the normal water is obtained ice a 9,26% faster than with softened water, but affecting its strength. The ice average formation speed is of 0, 5556 kg/h.