| 1 | The Effect of Non-equilibrium Condensation on the Drag Coefficient in a Transonic Airfoil Flow显示文摘In this study,a transonic flow past NACA0012 profile at angle of attack α=00 whose aspect ratio AR is 1.0 with non-equilibrium condensation is analyzed by numerical analysis using a TVD scheme and is investigated using an intermittent indraft type supersonic wind tunnel.Transonic flows of 0.78-0.90 in free stream Mach number with the variations of the stagnation relative humidity(Φ0)are tested.For the same free stream Mach number,the increase in Φ0 causes decrease in the drag coefficient of profile which is composed of the drag components of form,viscous and wave.In the case of the same M∞ and T0,for more than Φ0=30%,despite the irreversibility of process in non-equilibrium condensation,the drag by shock wave decreases considerably with the increase of Φ0.On the other hand,it shows that the effect of condensation on the drag coefficients of form and viscous is negligible.As an example,the decreasing rate in the drag coefficient of profile caused by the influence of non-equilibrium condensation for the case of M∞=0.9 and Φ0=50% amounts to 34%.Also,it were turned out that the size of supersonic bubble(that is,the maximum height of supersonic zone)and the deviation of pressure coefficient from the value for M=1 decrease with the increase of Φ0 for the same M∞. | I.W.Kim M.M.A.Alam S.J.Lee Y.D.Kwon S.B.Kwon | 2012 | Journal of Thermal Science2012，21，6： | 1 |
| 2 | 短纤维胶料的疲劳耐久性和粘弹滞后性能显示文摘由短纤维和橡胶组合构成的材料(短纤维胶料或称 SERC),如同由连续帘布和橡胶构成的复合材料那样,其性能得到改善。例如,这些复合材料的刚性要比纯橡胶的高。对于短纤维,很多年来人们已对它作了深入的研究。将短纤维加到橡胶中要比在连续帘布上擦胶容易。因此,可望轮胎公司会在充气轮胎的结构中增加对短纤维胶料的使用。但是,目前轮胎制造厂还不曾大量使用短纤维胶料。其原因之一是,短纤维在作为橡胶的增强材料为产品提供某些理想性能的同时,还使周期性应变过程中的粘弹滞后现象(VH)加剧。 | Y.D.Kwon 张洪珍 | 1991 | 橡胶译丛1991，，4： | 0 |
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