Identification of thermal characteristics of traditional Russian stove based on computational fluid dynamics and energy performance analyses

The energy utilization increases day by day based on the increment of population. The new technologies focus on finding the efficient ways on energy usage to reduce the energy consumption. The energy consumption of the residential sector occupies 25% of the total energy consumption all over the world. Likewise, the space heating consumption is the major consumption component in the residential sectors of cold climates. These circumstances indicate the necessity of the research to improve the energy performance of the heating systems. In this study, energy performance of a traditional heating system, Russian stove, is examined based on its unique architectural detailing and energy performance. Russian stove is a commonly used heating system in Kars region where it is located at the east side of Turkey. This study is divided in two steps as computational fluid dynamics and energy performance analysis to evaluate the performance of the Russian stove. Furthermore, a comparative analysis between Russian stove and conventional chimney with a steel casting stove were done. A meticulous investigations were performed on applied materials and architectural design of the chimneys. The main material of the Russian stove is firestone, however, the steel casting is used in the case of contemporary stove. Addition to the applied material analysis, the chimney design of the stoves were specifically analyzed. Russian chimney has a labyrinth path design while the steel casting stove has a straight path. The uniqueness of the chimney is arisen by its S shaped flue path, as mentioned above. S shaped flue path lets the heated air move slowly through the outlet of the chimney. Therefore, heated air, which is like 450°C, stays at the inside of the stove for a longer period by achieving a better heat transfer. Furthermore, S shaped design creates more internal surface area rather than straight chimney design that this design provides a better heat transfer with increased transfer surface area. In this research, the original design of Russian stove was investigated in terms of energy efficiency and thermal comfort. Hence, computational fluid dynamic Software was used to evaluate the generated heat flux, thermal gradient and predicted mean vote by transient solution mode in a two story building. The evaluation was performed for both heating and standby period, separately. Besides, the thermal mass characteristic of the stoves were assessed to show the features of the used material. In computational fluid dynamics analysis, Low Re k-epsilon turbulence model was used. Also, Petrov-Galerkin solution method, which uses second order differential equations, was chosen. Thus, the natural ventilation and occurred secondary flows in the stove were examined. Addition to the computational fluid dynamic analysis, the heating demand of the building was simulated by energy performance simulation software and the results were compared in this purpose. The mesh enhancement study was performed to provide the accuracy on the results. The mesh enhancements were repeated until the mesh independency was obtained at the level of 5%. The analyses showed that, in the case of straight chimney steel casting stove, an overheating formation was observed after 3 hours and the temperature was found as 29.87°C after 6 hours heating period. Also, overheating affected the predicted mean vote as 2.71, negatively during the heating period. On the standby period, the temperature reduced significantly to 16.50°C in 6 hours and the predicted mean vote value was -1.4. In the case of Russian stove, a homogenous heating was formed in the building and by the result of homogeneous heating, the predicted mean vote was obtained 0.3 in the heating period. Addition to this, it was observed that the generated temperature gradient was kept for 6 hours during the standby period in the building and the predicted mean vote was found as -1. In the comparison of Russian stove and steel casting stove results, the generated heat flux was found more in the Russian stove case stove by 22% In the conclusion of these results, in the case of Russian stove it is seen that the used material creates a thermal mass based on the high specific heat value and the unique S shape design of the Russian stove has a major effect on the thermal comfort. The existing literature of the Russian stove was limited only by hand workmanship information. However, this research extended it to the scientific knowledge by identifying the major specifications of the system's thermal performance. The research was utilized the energy performance and computational fluid dynamics analyses. Consequently, it is shown that this system is an example of a collaborative work between architecture, material science and engineering disciplines to obtain a high performance heating system. The integration of this system to the apartment building that has multiple residential units can be studied as the next step of this research.