Study On Correction Methods Of Ship Speed Trial Results

The general philosophy, correction items, calculation process, advantages and disadvantages of different correction methods are compared and analyzed.Based on ISO method, some improvements are made to evaluate speed and power performances more simply. A speed correction calculation model is presented. The most comprehensive correction items, such as wind, current, wave, steering, drift, water temperature & salt content, vessel condition, shallow water effect, and so on, are considered in this method.Gerritsma-Beukelma method is applied to predict added resistance in wave. A relevant ship model test is carried out to verify the method above. It is concluded that the theoretic method is acceptable by comparing with model test results.A correction calculation program is developed using VC language and applied to two different examples of ship speed trial data analysis. It is shown that this program is reliable and practical.