Experimental investigations have been carried out for impingement heat transfer characteristics of an enclosed dual swirling flame for various enclosure configurations. Effects of the size of the enclosure (D_E = 70 mm, 90 mm, 90 mm, 110 mm and 150 mm) and the level of gap between the top of the enclosure and the target surface (G = 12, 16, 20, 24 and 28 mm) have been examined at fixed other operating conditions (Re(o), H/D_h and S). In addition to this, the effects of variation in outer swirling flame Reynolds numbers (Re(o) = 7000–13,000), dimensionless separation distances (H/D_h = 2–5) and the swirl number (S = 0.86, 1.54 and 2.4) have also been examined. Impingement heat transfer characteristics strongly depend on the size of the enclosure (D_E) and the level of gap (G). Larger sized enclosures (D_E of 110 and 150 mm) with smaller gap levels (G of 12 and 16 mm) perform much better than small sized enclosures (D_E of 70 and 80 mm) with larger gap levels (G of 24 and 28 mm). Heat transfer performance continuously increases with an increase in Re(o) in presence of an enclosure in contrast to unenclosed flames where performance deteriorates at high Re(o). The heat transfer enhancement effect in presence of enclosure is more pronounced at larger separation distances (H/D_h of 4 and 5) because of the formation of the outer recirculation zone (ORZ). The effect of the presence of enclosure on impingement heat transfer enhancement becomes more significant at higher levels of swirl.

已经进行了针对各种封闭结构的封闭双涡旋火焰的冲击传热特性的实验研究。外壳尺寸（D _E  = 70毫米，90毫米，90毫米，110毫米和150毫米）以及外壳顶部和目标表面之间的间隙水平（G = 12、16、20，在固定的其他操作条件下（Re（o），H / D _h和S）检查了24mm和28mm ）。除此之外，外部回旋火焰雷诺数（Re（o）= 7000-13,000），无量纲分离距离（H / D _h  = 2-5）和回旋数（S = 0.86、1.54和2.4）也已经检查过。碰撞传热特性在很大程度上取决于外壳的尺寸（D _E）和差距水平（G）。具有较小间隙水平（G为12和16毫米）的大尺寸外壳（D _E为110和150毫米）比具有较大间隙水平（G为24和28）的小尺寸外壳（D _E为70和80毫米）要好得多毫米）。与在高Re（o）下性能下降的未封闭火焰相反，在封闭环境下，传热性能随着Re（o）的增加而连续提高。由于存在外部再循环区（ORZ），因此在较大的分隔距离（H / D _h为4和5）下，存在外壳时传热增强效果更加明显。外壳的存在对冲击传热增强的影响在更高的旋流水平下变得更加明显。