Pyroelectric sensor for entropy measurements

In this contribution we propose a system to measure entropy fluctuations in thermal systems. The system consist of a pyroelectric sensor and a temperature sensor. The pyroelectric convert thermal variations into electrical signals so that thermally induced charge is measured and monitored and heat variation can be obtained. Temperature is independently obtained with thermistors. Combining heat and temperature measurements, it is possible to infer thermal thermodynamic entropy variations in the sensor. Two types of measurements are carried out: volume, to measure entropy bulk changes and surface, to measure entropy flux through the system wall. Model simulations agree with experimental results. These results open the possibility to entropy monitoring in thermal process to improve systems performance.