超臨界状態は、圧力が臨界圧以上、温度は臨界温度付近（あるいは以上）の状態を指す。超臨界流体は超臨界抽出、汚染物処理など化学プロセス、超臨界水ボイラ・遷臨界CO2ヒートポンプなど幅広く応用されている。 超臨界流体の物性の温度、圧力依存性および流動・伝熱特性の解明が重要である。

本研究は、超臨界圧状態のCO2、水および新冷媒の加熱、冷却過程における熱移動現象を理論解析、数値計算と実験測定により解明する、また、超臨界流体を利用遷した臨界CO2ヒートポンプ、熱回収ランキンサイクルのサイクル特性と、超臨界流体に適する最適な熱交換器形状などを検討する。

具体的な取り組みは下記の通りである：

• マイクロスケールチャネルにおける超臨界流体の流れ、伝熱特性の解明．
• 排熱回収発電サイクル用超臨界冷媒の伝熱特性の研究．
• 排熱回収発電サイクルのサイクル特性の研究．
• 遷臨界CO2ヒートポンプのサイクル特性の研究．

参考文献

Xiaoxiao Xu, Yangyang Wu, Chao Liu, Kaizheng Wang, Chaobin Dang, Wanjin Bai, " Experimental investigation on heat transfer characteristics of supercritical CO2 cooled in horizontal helically coiled tube "，International Journal of Refrigeration, In press (2016) [doi: 10.1016/j.ijrefrig.2016.03.010]

Kaizheng Wang, Xiao Xiao Xu,Yangyang Wu, Chao Liu, Chaobin Dang, " Numerical investigation on heat transfer of supercritical CO2 in heated helically coiled tubes";Journal of Supercritical Fluids ; 99, 112-120 (2015) [doi:10.1016/j.supflu.2015.02.001]

Chaobin Dang, Keitaro Hoshika, Eiji Hihara, "Effect of lubricating oil on the flow and heat transfer characteristics of supercritical carbon dioxide" International Journal of Refrigeration 35, 1410-1417 (2012)

Chaobin Dang, Eiji Hihara, "Predicting the cooling heat transfer coefficient of supercritical CO2 with a small amount of entrained lubricating oil by using the neural network method " International Journal of Refrigeration 35, 1130-1138 (2012)

Chaobin Dang, Eiji Hihara, "Numerical study on in-tube laminar heat transfer of supercritical fluids," Applied Thermal Engineering 13, 1567-1573 (2010)

Chaobin Dang, Koji Iino, Eiji Hihara, Effect of PAG-type lubricating oil on heat transfer characteristics of supercritical carbon dioxide cooled inside a small internally grooved tube, Int. J. Refrigeration 33, 558-565 (2010)

Chaobin Dang, Koji Iino, Eiji Hihara, Study on two-phase flow pattern of supercritical carbon dioxide with entrained PAG-type lubricating oil in a gas cooler, Int. J. Refrigeration. Vol.31, No.7, 1265-1272, (2008).

Chaobin Dang, Koji Iino, Fukuoka K., Eiji Hihara., Effect of lubricating oil on cooling heat transfer of supercritical carbon dioxide, Int. J. Refrigeration. Vol.30, pp.724-731, (2007).

Chaobin Dang, Eiji Hihara, In-tube cooling heat transfer of supercritical carbon dioxide，part 1: experimental measurement, Int. J. Refrigeration, Vol.27, pp.736-747. (2004).

Chaobin Dang, Eiji Hihara, In-tube cooling heat transfer of supercritical carbon dioxide，part 2: comparison of different turbulence models, Int. J. Refrigeration, Vol.27, pp.748-760. (2004).

Chaobin Dang., Eiji Hihara., Cooling heat transfer of supercritical carbon dioxide, Refrigeration, Vol.79，No.920，pp.7-8, 2004. (Japanese)

Chaobin Dang, Eiji Hihara, Cooling heat transfer of supercritical carbon dioxide, 1st report: Numerical calculation and experimental results，Transactions of the Japan Society of Refrigerating and Air Conditioning Engineers, Vol.20，No.2，pp.163-173. (2003), (Japanese)

Chaobin Dang, Eiji Hihara, Cooling heat transfer of supercritical carbon dioxide, 2st report: A new correlation for heat transfer coefficient and the effect of lubricant oil, , Transactions of the Japan Society of Refrigerating and Air Conditioning Engineers，Vol.20，No.2，pp.175-183, (2003).