Kunping Lin

Experimental study on the thermal performance of the shape-stabilized phase change material floor used in passive solar buildings

The novel shape-stabilized phase change material (PCM) has the following salient features: large apparent specific heat for the phase change temperature region, suitable thermal conductivity, and the ability to keep the shape stabilized when it undergoes a phase change. In this technical brief, we put forward a kind of shape-stabilized PCM floor that is able to absorb solar radiation energy in the daytime and to release the heat at night in winter. The thermal performance of a prototype room using such a floor was studied. The experiments show that the mean indoor temperature of a room with the PCM floor is about 2°C higher than that of the room without a PCM floor, and the indoor temperature swing range is obviously minimized. Therefore, installing shape-stabilized PCM in a room may increase the degree of thermal comfort and reduce space heating energy consumption in winter In addition, the experimental results provide data for modeling and simulation research for such PCM floor systems.

Experimental Study of Underfloor Air Supply System With Air Solar Collector and Shape-Stabilized PCM

In this paper, a new kind of solar energy heating system with shape-stabilized PCM is put forward. It can absorb the solar energy in the daytime and release the heat at night in winter. The solar radiation energy was gained by air solar collector, and the heated air was sent to the underfloor space of the room with ducts at daytime. Then the thermal energy was stored in the shape-stabilized PCM plates. The shape-stabilized PCM can keep the shape stabilized when PCM undergoes a phase change because it is microencapsulated by the supporting material. At night the heat energy stored in the PCM could be released into the room by the ductless air supply. The thermal performance of a room using such system was experimentally studied. The experiments show that the thermal comfort degree of solar buildings can be improved when applying shape-stabilized PCM suitably. The conventional space heating energy consumption in winter can be greatly saved. Besides, the experimental results provide the data for further modeling and simulation research of such kind of system.Copyright

Influence of Additives on Thermal Conductivity of Shape-Stabilized Phase Change Material

Shape-stabilized phase change material (PCM) is a kind of novel thermal energy storage material. Its thermal conductivity is low, which tends to be bottleneck of applying it in many conditions. In this paper, additives with high thermal conductivities were doped in it to improve its thermal conductivity. The thermal conductivity was measured by a thermal probe. The experimental results show that the thermal conductivity of the shape-stabilized PCM can be improved greatly by adding exfoliated graphite. An empirical equation was got for calculating the effective thermal conductivity of the shape-stabilized PCM with different mass fraction of graphite additive. By using the so-called numerical element method, a theoretical equation was obtained for predicting the effective thermal conductivity, which agrees well with the experimental results. The empirical equation and the theoretical prediction are useful for “designing” and controlling the thermal conductivity of the shape-stabilized PCM.Copyright

Model and Simulation on Thermal Performance of Shape-Stabilized Phase Change Material Floor

Shape-stabilized phase change material (PCM) is a kind of novel PCM. It has the following salient features: large apparent specific heat for phase change temperature region, suitable thermal conductivity, no container. In the present paper, a kind of floor based upon shape-stabilized PCM is put forward which can adsorb the solar radiation energy in the daytime and release the heat at night in winter. Therefore, in winter the indoor climate can be improved and the energy consumption for space heating may be greatly reduced. A model of analyzing the thermal performance of this shape-stabilized PCM is developed. By using the model, the influence of various factors (thickness of PCM layer, melting temperature, heat of fusion, thermal conductivity of PCM etc.) on the thermal performance is analyzed. The model is verified with the experimental results. The model and the analysis are helpful for the application of shape-stabilized PCM based floor in solar energy buildings.Copyright

Experimental Research on Thermal Performance of Shape-Stabilized Phase Change Material Floor

Experimental study was conducted on the thermal performance and energy saving effect of a room with shape-stabilized phase change material (PCM). The results showed that the mean indoor temperature of the room with PCM floor was about 2°C higher than that of the room with normal floor and the indoor temperature swing range narrowed greatly. The results also manifested that by applying shape-stabilized PCM in room suitably, the thermal comfort level could be raised and space heating energy in winter could be saved. Finally, the experimental results enriched the database for the further modeling and simulation research.Copyright