Study of the Vertical Distribution of Air Temperature in Warehouses

Warehouses are usually large, plain industrial buildings commonly used for storage of goods. Vertical distribution of air temperature is an important aspect for indoor environment design, which must be taken into account by architects and engineers in the early stages of warehouse design. The aim of this work is to analyze the vertical temperature gradients existing in warehouses, quantifying their value and analyzing their evolution along the year. To do so, the study outlines the monitoring of several warehouses with different building typology and height located in different areas of Spain for a complete annual cycle. The results obtained when applying a simple linear regression analysis to 175,200 vertical temperature profiles show that there is a strong influence of the outdoor temperature over the stratification of the indoor air. During warm months, the ceiling and the upper strata get warmer, whereas the cold air accumulates in the lower levels, increasing the stratification of indoor air (maximum values between 0.3 °C/m and 0.7 °C/m). During cold months, the ceiling gets cold due to its contact with the outdoor air, therefore, the colder, heavier air moves down to the lower strata, registering insignificant vertical temperature differences. Air conditioning of the warehouse, besides controlling the temperature, limits the influence of the outdoor environment on the stratification of temperatures. The results of the study may be of great use for warehouses for products sensitive to temperature, which may suffer a different evolution, conservation or maturation when the temperature differences are maintained for a long time.