| Huizhou traditional dwellings, as significant parts in Chinese traditional culture,are the wisdom of ancestors. In recent years, the administration of Huangshan city in Anhui province newly issued a series of policies and different projects to protect Huizhou traditional dwellings, like “Protecting one thousand dwellings distributed in one hundred villages” as well as “Reinforcing the non-Huizhou architecture and surroundings to shape traditional Huizhou”. However, these polices usually emphasize the unique architectural styles and ignore the design strategies. The passive energy efficient strategies are supposed to inherit and develop in modern architectures.Based on the research on formation mechanism of indoor environment in winter, the solutions are supposed to be proposed and evaluated in this study to facilitate the heritage and renovation of traditional dwellings.Filed measurement is firstly carried out to study the indoor environment situation in Huizhou traditional dwellings in winter. Computational Fluid Dynamics(CFD)software is then adopted to study the impact of ventilation on indoor thermal environment. Building simulation(BS) method is applied to investigate the impact of thermal performance of building envelop, intensity of internal heat source and ventilation rate on indoor thermal environment. The mathematical model between outdoor wind speed and ventilation rate is developed in Fluent, which is imported into Trnsys to calculate the coupling of ventilation and thermal environment. The coupling model can be used to evaluate and obtain these optimal solutions.The index of Predicted Mean Vote(PMV) is-3 and Predicted Percentage of Dissatisfied(PPD) is 100% are obtained from the measured data of traditional houses,i.e. indoor temperature, humidity, thermal comfort, air tightness, wall temperature and ground temperature, indicating that the indoor temperature and humidity cannot satisfy the requirement of current standards. On the condition of closing openings,ACH(air change rates) is 10.1 times /h and 2.5 times /h in the halls and rooms respectively, which indicates that air change rates in both halls and rooms is poor. In addition, thermal insulation of the building envelope cannot meet the requirement of energy conservation in residential construction. Therefore, ventilation calculation models of single wing opening, two openings hall, patio opening are developed in this study to investigate the regular pattern of indoor air temperature in two simulationconditions(i.e. openings are fully open, openings are fully closed) as well as the air temperature and speed distribution of the door openings. Results show that air flow passage in the hall is the main reason leading to a lower indoor temperature in winter.Temperature under the condition of opening closed is higher than open by2?.Meanwhile, the maximum air flow of rooms' openings is located at the top and bottom of the openings. The increase of air tightness of the room, heat intensity and thermal performance of building envelope can cause an increase in the indoor temperature, and air change rates have a significant impact on the indoor temperature.Several solutions are proposed for the current poor indoor thermal environment of Huizhou traditional dwellings in winter on the basis of the design codes in Germany passive houses. They are listed as follow: converting the heat transfer coefficient of building envelope to 0.15W/(m2·K), ensuring the ventilation rate with0.6 times/h as well as controlling the heat intensity within 10W/m2. Applying the above setting parameters, the average indoor temperature is obtained to be 20.8? and the relative humidity is 31.12% by Trnsys simulation, which meets the requirement of the current standard. Specially, the increases of air tightness, supplementary heat source and thermal performance of building envelope account for 67%, 7% and 26%respectively for the contribution on the increase of indoor temperature. |
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