International Scientific Journal

Thermal Science - Online First

online first only

Smart capacitive moisture sensor calibration in mineral wool and green roof soil substrate

The environmental benefits of green roofs have been widely recognized. In recent years, increasing attention has been paid to moisture management in the green roof systems. The moisture in the green roof has an influence on its thermal and hydrological performances. An accurate measurement of water content in green roof substrate is important for irrigation monitoring, optimal irrigation management, and plant growth. Knowing the performance and characteristics of the sensor for the chosen substrate layer in a green roof system is essential. This paper presents laboratory calibration of the capacitive moisture sensor in two types of the green roof substrate layer. The volumetric water content of several mineral wool and soil samples, with the water content from low until saturated, were measured using the gravimetric method and related to frequency obtained by the sensor. The results have shown that the capacitive moisture sensor has a good response to water content variation. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no.III42008: Improving the energy performance and the indoor air quality of educational institution buildings in Serbia with the impact on health]
PAPER REVISED: 2020-07-10
PAPER ACCEPTED: 2020-07-24
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