Research on the Scale Effect of Drag Reduction of Ships by Microbubbles Technology
Mixture gas-liquid two-phase flow model and RNG k-e turbulence model were selected,and the numerical model of microbubble drag reduction was constructed considering the two-phase force.The reliability of the method was verified by the experimental data of flat microbubble drag reduction.The drag reduction of ship model microbubbles with different scales under the same Froude number was simulated,and the calculation results of different scales and different working conditions were compared to analyze the similar law of ship microbubble drag reduction.The results show that the small-scale ship model is easy to reach gas flow saturation,and the drag reduction rate is not affected much by increasing the air injection volume.When the scale ratio λ is 20,the maximum drag reduction rate can reach 16％.With the scale of the model gradually increasing,when λ is 20,15 and 10 respec-tively,the drag reduction rate of the ship model has a decreasing trend of about 1.5％under the condi-tion of satisfying the same Froude number and jet speed.
万方数据
维普
