Research On Scale Impact Of Wave Distorted Model Test

In recent years, the unceasing expansion of construction on port and harbor works (such as dayaowan project) causes the water areas which the wave physical model test involved become larger, considering that the depth and wave height of undistorted model may be too small to satisfy precision on the condition of limiting laboratory space, distorted model test need to be used. However, on the condition that the influence of wave refraction diffraction and reflection are obvious, the actual deviation of calculation results between distorted model and prototype may be great so that the results of distorted model test aren't accepted widely at present, because the similitude relationships of the wave movement are difficult to satisfied simultaneously. With the development of computer technologies and the progress of calculating methods, numerical model with the advantages of multi-plan short period and less investment is becoming a main method on solving problem of water project. Consequently, it is very significant for studying the distortion ratio of model test with numerical model and conducting physical testFirstly, based on the Boussinesq module in MIKE21 software system, distorted models of different distortion ratio under the main condition of refraction or diffraction are established and the numerical simulations of wave height distribution in the harbors of different distortion ratio models are done by the traditional similitude relationship of the wave movement. The incident wave is irregular waves, and the range of distortion ratio is 1³. By comparing the calculation results of different distorted models as well as undistorted model with prototype, the influence of distortion ratio on test results is discussed and the application range of distortion ratio is presented in different conditions.In the second place, the numerical computations for different models of dayaowan harbor are carried out on the above basis. It is concluded that the calculation results of undistorted model and prototype are in good agreement, but the error is larger for distorted model. Accordingly, a new similitude relationship( λ_l = λ_l, ·λ_thkh ) of wave movement is presented in the way that the time scale of undistorted model is applied to calculate wave length scale of distorted model. The computations of distorted model in different wave length scales show that the error between distorted model and prototype under λ_L = λ_l· λ_thkh is less than that under wave refraction and diffraction similitude. Furthermore, the similitude relationship is also proved on the condition of different incidence wave direction and differentdistortion ratio. In addition, the influence of wave parameter on test result is studied on the basis of \=A,- Xthkh, it shows that the effect of incident wave height on computation resultsof distorted model is small, but the effect of wave period is obvious.Finally, the numerical computations for wave distorted models of Jingtang harbor are carried out under the condition of different wave length scales in which the phenomenon of wave refraction, diffraction and reflection are also obvious. It is concluded that the error between distorted model and prototype under \ = ^,- ^,m is also less than that under the condition of wave refraction and diffraction similitude by comparing the computation results of different distorted models.