The design strategy and testing of an efficient floor anti-freezing ventilation system in a large cold store

In this study, an optimization strategy of mechanical ventilation was carried out to reduce frost heaving and heating power in a large cold storage operation. Then, a response surface method is used to determine influential factors and mechanisms of mechanical ventilation by using a standard pre-assembled cold storage system as a test case. Results show that the main factors affecting the soil surface temperature critical to frost-heaving prevention include the soil temperature, airflow speed, pipe diameter, and pipe spacing. For a case study, the spacing of the ventilation pipes has the most significant influence on the surface temperature of the soil layer. In contrast, the soil temperature at a depth of 3.2 m has a minor impact on the surface temperature. Especially for the design criteria that the soil surface temperature cannot be less than 2 degrees C, the diameter of the ventilation pipe should be greater than 0.28 m, the spacing of the ventilation pipe should be less than 1.01 m and the airflow speed should be greater than 2.09 m<middle dot>s-1.