Dynamic modeling of thermal behavior of a solar floor heating system for a HAMMAM in Marrakech

This paper deals with the energy performances and thermal behavior of a solar system for space heating of a Turkish bathroom (Hammam) through a heated floor, in Marrakech. Two configurations with or without thermal storage were compared. Moreover, an optimization study has been made for the collector area, the inclination of the solar collectors, storage tank, pipes material and pumps flow rates. Dynamic simulation of the Hammam coupled with the floor heating system was conducted using TRNSYS software. The Hammam was monitored via air temperature and humidity measurements during four days of the 2015 winter season. Simulations and monitoring results are compared using in-situ measured weather data, while the parametric study was performed along a typical meteorological data (TMY). Comparison between simulation and experimental results showed good accordance with a maximum deviation of 1.5 °C and a maximum relative difference less than 4%. Simulation results show that the system without thermal storage allows the Hammam operative temperature to reach the desired one, since it ranges between 36 °C and 39 °C for a sunny day in winter; while the system with thermal storage leads to at least 10 °C operative temperature lower compared to system without thermal storage. In addition, the former allows having quasi-constant floor temperature that depends on the storage volume, so it avoids day/night temperature large fluctuations thanks to thermal storage inertia. Nevertheless, the configuration of the floor heating system with a storage tank does not achieve the desired temperature for the floor of the Hammam. Furthermore, results of simulations show that the use of serpentine of PEX tubes, 4 m2 water solar collectors with 80 kg.h-1 flow rate works properly for the configuration without thermal storage, since the Hammam air temperature has to be maintained at around 37 °C.