SWATH船的縱向運動仿真及穩定性分析

論文字數:17610,頁數:50

SWATH船的縱向運動仿真及穩定性分析

摘  要：SWATH船是一種具有優良耐波性的新型高性能船舶。SWATH船縱向運動的穩定性，是SWATH船穩定性的主要決定因素，本文根據勞斯-赫爾維茨判據分析了SWATH船縱向運動的穩定性，給出了適合工程應用的縱向運動穩定性簡化判據和臨界巡航速度的計算方法。
 SWATH船縱向運動仿真主要是在規則浪中和不規則浪中對SWATH船的縱向運動性能進行仿真，通過仿真結果分析船的縱向運動性能，以及加穩定鰭和不加穩定鰭對SWATH船縱向運動性能的影響。
 由于其水線面積較小，船的縱傾恢復力矩相應減少，隨著速度的增加，作用在水下潛體上的Munk力矩迅速增大，是導致SWATH船縱向和橫向運動不穩定的重要原因。為保證穩定性，可以通過增加穩定鰭來解決這一問題，同時，也可以進一步改善SWATH船的耐波性能。
 另外，穩定鰭的安裝位置、展弦比、面積等參數都影響SWATH船縱向運動的穩定性。其中，首鰭的作用一方面促進失穩，但另一方卻可以提高振蕩響應的收斂速度 ，通常都與尾鰭組合使用，其面積比尾鰭明顯��；尾鰭面積增大和位置后移均有利于提高穩定性，但它們都受到船舶結構的限制。
關鍵詞：小水線面雙體船；Munk力矩；縱向運動；穩定性判據

Longituidnal motion simulation and stability analysis of SWATH
Abstract: SWATH is a kind of new high performance ship with the excel seaworthiness.The stability of the longitudinal motion of SWATH is the important part of SWATH stability. This paper analyzes stability of longitudinal motion of SWATH according to Routh – Hurwitz stability criterion. A simplified method to determine stability of longitudinal motion and to calculate the critical speed for engineering purpose is introduced.
 The simulation of longitudinal motion of SWATH is mainly about the simulation of the longitudinal motion performance of SWATH in regular and irregular wave. According to the simulation results, the longitudinal motion performance of SWATH and the distinction between the situation with stabilizing fins and that without stabilizing fins were analysed
 The restoring moment of the longitudinal motion of SWATH is small because of the small waterline area. With the speed increasing, MUNK moment acted on the lower hulls increases quickly. The MUNK moment is the main factor that results in the unstability of SWATH. In order to ensure the stability of SWATH, the stabilizing fins can be adopted. And this all can improve the seaworthiness of SWATH.
 In addition, the parameters such as position, aspect ratio, area etc. affect stability of longitudinal motion. For example, the forward fin can promote unstability, but it can accelerate the convergence of the longitudinal motion oscillation SWATH. And it is usually used in combination with the tail fin. The area of forward fin is also smaller than the tail fin. Increasing the tail area can also improve the stability of SWATH, but it cann’t exceed the structure limit of SWATH.
 Keywords: small waterplane area twin-hulls;  Munk moment ; longitudinal motion ; Stability criteria

目    錄
 
1  緒論 1
1.1  課題的來源、意義和研究現狀 1
1.2  SWATH船的結構及特點 2
1.3  SWATH船的發展趨勢 4
1.4  課題的基本內容 5
2  SWATH船縱向運動的模型及穩定性分析 6
2.1  波浪中SWATH船的縱向運動數學模型 6
2.2  靜水中SWATH船的縱向運動數學模型 7
2.3  SWATH船縱向運動的穩定性判據 8
2.4  SWATH船縱向運動的三個特征參數 10
2.5  航速對SWATH船縱向運動穩定性的影響 10
2.6  本章小結 15
3  MATLAB仿真 16
3.1  海浪仿真 16
3.2  長峰波隨機海浪中垂蕩力（ZZ）和縱搖力矩（MM）的仿真 17
3.3  SWATH船的縱向運動仿真 29
3.4  利用特征根分布圖分析SWATH船的穩定性 34
3.5  本章小結 39
結  論 40
致  謝 41
參 考 文 獻 42
附   錄 43