Recently in Japan, it has been popular to install VRF (Variable Refrigerant Flow) heat pump system to office buildings regardless of size and shape, because many Japanese regard it as the virtue to turn off the air conditioner frequently for energy saving if it is not necessary. This system consists of packaged outdoor unit and multi indoor units connected by refrigerant pipe, and there are some merits for users and owners. For example, it is easy to design for planning building system because of standardized system. Moreover, this system contributes to saving energy and to increasing comfort for users, because it can be operated adequate indoor unit as necessary. On the other hand, because refrigerant flow rate changes dynamically depend on load condition, this system needs complicated control system for keeping stable operation under many manipulating elements. For that reason, it is too difficult to find adequate each elements' condition by only experimental study. In order to evaluate VRF system by easy way, we build the numerical simulation model based on law of physics and we research adequate control condition under various sorts of cooling condition. It is said that conventional control method occurs uns table manipulating condition in case of changing load condition. In this report, we reproduce unstable condition of expansion valve by simulation study.
|出版ステータス||Published - 2018 1 1|
|イベント||9th Asian Conference on Refrigeration and Air-Conditioning, ACRA 2018 - Sapporo, Hokkaido, Japan|
継続期間: 2018 6 10 → 2018 6 13
|Other||9th Asian Conference on Refrigeration and Air-Conditioning, ACRA 2018|
|Period||18/6/10 → 18/6/13|
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