The coupling heat transfer of hot water heating system based on thermal utilization of a burning cave in a rural house of northern China

摘要

In order to solve the practical problems on the utilization of a burning cave, such as overheated floor, uneven heat distribution, and serious heat lose, a hot water heating system integrated with a burning cave has been designed based on the principle of energy cascade utilization. However, there is no prediction and calculation method for designing this combined heating system. In this paper, through theoretical calculation, the response formula of time-temperature on the hot water heating system changed with the radiation intensity on biomass fuel combustion layer has been deduced and verified by experimental data. Besides, the impacts of the radiation temperature on fuel combustion layer, the height of fuel layer, pipe diameter, pipe spacing and water flow velocity on the heat transfer performance of this heating system have been respectively discussed. The thermal efficiency can be up to 39.3%. (C) 2015 Elsevier B.V. All rights reserved.