An Experimental Study On Low Surface Energy Coatings To Influence Of The Drag And Noise Reduction Effect

The object moves in viscous fluid will accepting two kinds of resistance, one kind is the friction drag that the fluid applied to the object directly, one kind is the pressure drag that because of separating the fluid and taking from, and this drag force can create the flow noise. This article considers the requriments of flow noise and resistance reduction for underwatert moving target with up-to-data material science research result to test and analyse flow noise and resistance reduction effect of the low surface energy dewatering coating.Firstly, this article analyses the relation between physical properties of the material and flow resistance and flow noise on theoretical aspect. The conclusion is that the surface material has the effect of reducing the flow resistance and noise because of its experimental on reducing the mutual action between fluid and solid surface under given conditions.Secondly, use the gravitational low noise water tunnel test condition and adopt torpedo model, many times test the flow noise, pressure pulsation and shell vibrationon of the torpedo model under diversity flow rate with have coating or not, and use strain gauge to measure the change of the fluid resistance.Finally, get coating flow noise and resistance reductiong effect change relation with different flow rate and coating thickness by analysis the large amount of measurement data. The test indicate that the low surface energy dewatering coatings have the certain drag and noise reduction effect under the high flow rate , and with the flow rate power-up ,the effect of the drag and noise reduction becomes better and better.but under the low flow rate ,the coating increase the drag and noise. The super-hydrophobic coating have noise reduction effect under all flow rate,and the effect become better and better with increasing of flow rate.