滑行艇气层减阻试验

通过对三种艇型及不同的喷气方式的模型试验，研究了断阶滑行艇模型气层减阻的实施途径及减阻效果，取得了总阻力减少25％以上 结果，提出了一种适合于采用气层减阻技术且阻力性能优良的艇型。垂向舭板可减少滑行艇的高速阻力，但阻力减少的程度与艇型有关。底部斜升角较小时，有利于气层减阻。气层减阻率大于舭板减阻率，对底部斜升角较大且艇底扭曲、艏部设置适当的纵向防溅条、舯部设置楔形板的深Ⅴ型艇，垂向舭板对其阻力的影响不大，这种深Ⅴ型艇的阻力性能较佳，若喷气，其总阻力还可进一步减少15％。孔喷时，孔径采0.5mm或1.3mm对模型阻力的影响甚微，采用0.4mm缝叶的模型阻力比用孔喷时略大，采用较大孔喷或缝喷有利于工程上的喷气实施。

Experimental Study on Resistance Reduction of Planing Craft by Air Injection

The effect of air injection on the resistance reduction of stepped planing craft models with different hull forms is investigated experimentally. Different air injection metheds are used. The total resistance is reduced up to 25%. A new type of planing craft, which is suitable for adopting resistance reduction by air injection and has high resistance performance, is proposed. The resistance of the planing craft at high speed can be reduced by vertical bilge barrier,but this kind of resistance reduction is related to the hull form of the craft. Low deadrise angle is favorable to resistance reduction by air injection. The percentage of resistance reduction by air injection is larger than that by the bilge barrier. To the deep V craft with twisted bottom, suitable bow spray strip and wedge at the mid ship, vertical bilge barrier has little effect on its resistance;this kind of deep V craft has excellent resistance performance, furthermore, its total resistance can be reduced by 15% with air injection. The difference of model resistance by using 0.5mm pore for air injection and 1.3mm pore is very small. The model resistance by slot injection is somewhat larger than that by pore injection. It is favorable in engineering application to adopt large pores or slots for air injection.