Database of real ship vibration prediction method

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Database of real ship vibration prediction method

Operator, additional water quality by the △ v = (1 + B / Zd) (1 +2.1 S (B / D a 0.275) (D / £)) estimates. Residual standard deviation of the regression test s smallest, the largest correlation index r, the best curve fitting station. Especially with the increase in tonnage, lower and lower natural frequency of the hull girder, the corresponding linear regression model has been unable to forecast the frequency value of the intercept B below (Figure 2), making the regression model to predict the scope has been limited. Summary of the analysis, the system uses the Y-Xe regression model to predict the characteristics of a variety of natural frequency values. The regression equation is as follows: - /. Figure 2 Frequency intercept of Dalian University of Technology 35, f a (, / BDE / (L.)) E (4) where: E is equivalent instead. Regression model taking into account the special nature of the limitations and sample, the system will be more reasonable to return to touch type and parameter list of the different equations are calculated using the weighted average of the results of these equations forecast inherent characteristics of the new real ship, that is f = 1Σ (5) where: Ⅳ is the number of ways; for a variety of methods weight; forecast results for a variety of ways. Described below are the different stages in the design of the natural frequency of forecast model instead of the equivalent of several selection. (1) design early prediction of natural frequency of vertical vibration of ED, 』; mound for a D. (2) The design natural frequency of vertical vibration of the final prediction of E a / (b D); E2 = where / (1 + a (i +1)) (6)-E / G · where / (As) (7 ) where: A is the shear area; is the elastic modulus; G is the shear modulus {i for the calculation of order form. (3) preliminary design level of natural frequency prediction E = B, 』; mound one. (4) final design level of natural frequency prediction of E: a / (rib). 3 An example of a tanker in Table 2 for the elements of the main scale, Table 3 is the application of the vibration characteristics of SDBASE system prediction results of Table 4 is the size of a ship superstructure and the superstructure with SDBASE system prediction values of the longitudinal natural frequency of vibration. Table 2 oil tankers principal particulars of a superstructure in Table 4 with the longitudinal vibration natural frequency scale projects drum m value L/mB/m/4/md/md/tCb/vbf221_02957l646l24466507O. 8l82l5.4l420.10 calculated bagel: (model child 1) 9.217 № (model 2) 8.804Hz Xie real value & 83H Table 3 Hz natural frequency value of the No. 5 Ma Jun et al: Prediction of vibration of the real ship The example shows that the database approach, the application SDBASE system has a natural frequency of forecasting accuracy, the error can be controlled in less than lO, and with the real data to enrich the ship, its accuracy can be further improved prediction for ship design provide the basis for the vibration . 4 Conclusion vibration data according to the actual prediction of the ship natural frequency characteristics of new vessels, not only can dynamically select the parameters in the regression equation coefficients, and the mother can choose a different type, more rational prediction of the vibration characteristics of new vessels, the error can be controlled 1O less. Features such as new ship natural frequency depends on the predictions of the accuracy of data in the database, the amount of representation and the size of the data itself, a more reasonable prediction should have five or more of the same type mother ship data, the possible elements of the main scale appropriate restrictions, such as captain, tonnage should not be too bad,[link widoczny dla zalogowanych], so the mother ship of the type of boat and the new Q have a good similarity.