成果報告書詳細 |
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管理番号 | 20120000000395 |

タイトル | *平成23年度中間年報 開発項目 高効率ノンフロン型空調機器技術の開発/冷媒の性能、安全性評価/エアコン用低GWP冷媒の性能および安全性評価 |

公開日 | 2012/6/9 |

報告書年度 | 2011 - 2011 |

委託先名 | 国立大学法人東京大学 |

プロジェクト番号 | P11008 |

部署名 | 環境部 |

和文要約 | 和文要約等以下本編抜粋：
1. 研究開発の内容及び成果等 (1) エアコンの性能評価法確立（東京大学担当） (1a）エアコンの使用実態把握 エアコンの使用実態を明らかにするため、関東地区に75台、信越地区に25台のルームエアコンを一般家庭に設置し、1年半にわたって使用時間を測定した。 |

英文要約 | (1) Performance evaluation method of air-conditioners (University of Tokyo)
The characteristics of the flow boiling heat transfer of R1234yf/R32 refrigerant mixtures are experimentally investigated. Experiments were conducted under a wide range of heat fluxes from 6 to 24 kW/m2 and mass fluxes from 100 to 400 kg/m2s in horizontal stainless steel tubes with inner diameters of 2 and 4 mm. The results revealed that the heat transfer coefficients of the mixture were 30?50% lower than that of pure R1234yf. The characteristics of the condensation heat transfer of an R1234yf/R32 refrigerant mixture are experimentally investigated. The experimental results are compared with the existing condensation heat transfer models. (2) Numerical simulation of diffusion of refrigerant leaking in a room (University of Tokyo) When flammable refrigerant leaks from an air conditioner, flammable region is generated, and ignition risk occurs. The risk is estimated from the size of flammable region and the existence probability of ignition source. The flammable region is numerically calculated at the leakage of flammable refrigerant from an air conditioner into habitation or inhabitable space. The simulation method of permeation of leaked gas into the room was investigated. (3) Flammability of 2L class refrigerants (AIST) Considering practical use of low GWP refrigerants, humidity effect on flammability of R-1234ze(E) has been examined. The calculated heat of combustion increases from 10.2 MJ/kg up to 10.7 MJ/kg by addition of humidity. Flammability limits have been measured by ASTM-E681 method. R-1234ze(E) was nonflammable in dry air. By addition of humidity it became flammable and its flammable range increased with increasing absolute humidity. At 23 degree C and 90% RH, the lower and upper flammability limits have been obtained as 5.9 and 12.6 vol%, respectively. The burning velocity increased as the absolute humidity increased. The maximum burning velocity of R-1234ze(E) was 5.2 cm/s at 7 vol% under the absolute humidity of 0.03. On the other hand, humidity did not affect the flammability properties for R-32. (4) Ignition energy of 2L class refrigerants (AIST) Lewis and Elbe presented two theoretical equations for minimum ignition energy based on a minimal flamelet model. However, the theoretical values derived by these equations are at least several times larger than the experimental values. We have revised the size of the minimal flamelet to find that the theoretical values obtained by one of the equations agree well to the observed values. In addition, the theoretical values by the other equation applying the revised flamelet size agree well to the observed values for strong fuels. |

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