本文選題：動力定位供應(yīng)船　切入點：流載荷　出處：《武漢理工大學》2014年碩士論文　論文類型：學位論文

【摘要】：本文以計算流體動力學Fluent為平臺，計算一定雷諾數(shù)范圍內(nèi)動力定位供應(yīng)船流載荷系數(shù)，并研究船型參數(shù)、呆木參數(shù)以及雷諾數(shù)對流載荷系數(shù)的影響規(guī)律，最終得到流載荷系數(shù)的估算方法。在計算動力定位供應(yīng)船之前，先對一艘有試驗資料的油船進行0~180°內(nèi)的流場計算，借由與試驗資料對比，對數(shù)值計算方法的合理性進行驗證，并通過分析船體表面壓力及剪切力，，總結(jié)粘壓阻力系數(shù)和摩擦阻力系數(shù)隨流向角的變化規(guī)律。然后以一艘動力定位供應(yīng)船為母型船，通過控制排水量和船長不變，對裸船進行船型變換，采用CFD方法計算一定雷諾數(shù)范圍內(nèi)裸船流載荷系數(shù)。通過變換母型船的呆木面積及形心位置，計算不同呆木參數(shù)下的流載荷系數(shù)。最終在考慮呆木參數(shù)及雷諾數(shù)的影響下，采用偏最小二乘回歸（PLS）對單個角度下的流載荷系數(shù)進行回歸，線性插值得到任意角度下的流載荷系數(shù)。數(shù)值計算方法及計算結(jié)果如下： （1）數(shù)值計算方法：計算域選擇內(nèi)域圓柱形，外域方形，當計算不同流向角下的流載荷時，只需轉(zhuǎn)動內(nèi)域網(wǎng)格。對于網(wǎng)格劃分提出了幾點不同于直航時的要求：稍微降低緊鄰船體表面區(qū)域的網(wǎng)格密度；減少平行中體處的網(wǎng)格間距；增加船體外圍的網(wǎng)格密度。選擇SST湍流模式進行定常計算，即適合低雷諾也適合高雷諾數(shù)。（2）針對動力定位供應(yīng)船的縱向流載荷系數(shù)，在小角度時，摩擦阻力系數(shù)占主要成分，在40°和130°時粘壓阻力系數(shù)劇增，40°~130°時，粘壓阻力系數(shù)占主要成分，且粘壓阻力系數(shù)與船首尾壓差在縱向上的投影相關(guān)。（3）針對動力定位供應(yīng)船的橫向流載荷系數(shù)，在60°左右達到峰值，該方向上的摩擦阻力系數(shù)較粘壓阻力系數(shù)為小量，可忽略不計，粘壓阻力系數(shù)由船首尾壓差在橫向上的投影決定；（4）添加的呆木，改變尾部壓力分布，增加尾部的漩渦阻力，導致流載荷系數(shù)增加，并回歸呆木的影響因子，且驗證估算公式的預(yù)測性良好；（5）雷諾數(shù)主要影響摩擦阻力系數(shù)，且隨著雷諾數(shù)的增加而減少；（6）影響流載荷系數(shù)的船型參數(shù)主要是方形系數(shù)Cb和船長船寬比L/B，通過偏最小二乘方法對單個流向角下的流載荷系數(shù)進行回歸，線性插值可得到任意角度下的流載荷系數(shù)，最終編寫流載荷系數(shù)計算程序。
[Abstract]:In this paper, based on the computational fluid dynamics (Fluent) platform, the flow load coefficients of the supply ship in a certain range of Reynolds numbers are calculated, and the influence of ship form parameters, stonewood parameters and Reynolds number convection load coefficients are studied. Finally, the method of estimating the flow load coefficient is obtained. Before calculating the dynamic positioning supply ship, the flow field of a tanker with test data is calculated within 180 擄, and the rationality of the numerical calculation method is verified by comparing with the test data. By analyzing the surface pressure and shear force of the hull, the variation law of the viscous pressure coefficient and friction resistance coefficient with the flow angle is summarized. Then a dynamic positioning supply ship is taken as the mother ship, and the displacement and the captain are not changed by controlling the displacement. In this paper, the ship form transformation of bare ship is carried out, and the flow load coefficient of bare ship is calculated by using CFD method in the range of certain Reynolds number. By changing the area and center of shape of the parent ship, Finally, considering the influence of parameters and Reynolds number, the flow load coefficient at a single angle is regressed by partial least square regression (PLS). The flow load coefficients at any angle are obtained by linear interpolation. The numerical method and results are as follows:. 1) numerical calculation method: the inner cylinder and the outer square are chosen in the computational domain. When calculating the flow load at different flow angles, It is necessary to rotate the mesh in the inner domain. The requirements of grid division are different from those of direct navigation: reducing the density of the grid near the hull surface, reducing the mesh spacing between the parallel bodies and the center of the ship, reducing the mesh density of the adjacent hull surface, reducing the space between the meshes. Choosing SST turbulence model for steady calculation, that is, suitable for both low Reynolds and high Reynolds number, for the longitudinal flow load coefficient of dynamic positioning supply ship, friction resistance coefficient is the main component when the angle is small. At 40 擄and 130 擄, the viscous pressure resistance coefficient accounts for the main component at 40 擄and 130 擄, and the longitudinal projection correlation between the viscous pressure coefficient and the pressure difference between the front and the tail of the ship is related to the transverse flow load coefficient of the dynamic positioning supply ship. At about 60 擄, the friction resistance coefficient in this direction is smaller than the viscous pressure coefficient, which can be ignored. The viscosity pressure coefficient is determined by the projection of the ship's head and tail pressure difference on the transverse side to change the tail pressure distribution. Increasing the swirl resistance in the tail leads to the increase of the flow load coefficient and the regression of the influence factors of the stumped wood, and it is verified that the prediction formula has a good predictability and the Reynolds number mainly affects the friction resistance coefficient. With the increase of Reynolds number, the ship form parameters affecting the flow load coefficient are mainly square coefficient CB and the captain's ship width ratio L / B. The flow load coefficient under a single flow direction angle is regressed by partial least square method. The flow load coefficient at any angle can be obtained by linear interpolation. Finally, a program for calculating the flow load coefficient is compiled.
【學位授予單位】：武漢理工大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：U662.2

【參考文獻】

相關(guān)期刊論文 前8條

1 周素蓮;聶武;白勇;;深水半潛式平臺系泊系統(tǒng)設(shè)計研究[J];船舶力學;2010年05期

2 王先福,楊建民,王磊;海上浮體動力定位外力計算[J];海洋工程;2005年03期

3 傅慧萍;楊晨俊;;雷諾數(shù)對船舶阻力和伴流場的影響[J];上海交通大學學報;2009年10期

4 繆燕華;吳斐文;;動力定位工程船設(shè)計技術(shù)研究[J];上海造船;2010年01期

5 王海燕;楊方廷;劉魯;;標準化系數(shù)與偏相關(guān)系數(shù)的比較與應(yīng)用[J];數(shù)量經(jīng)濟技術(shù)經(jīng)濟研究;2006年09期

6 曹明強;王磊;王亮;;深水半潛平臺海流載荷試驗分析[J];實驗室研究與探索;2009年08期

7 楊利敏;;單點系泊船舶在風浪流聯(lián)合作用下的平衡位置和受力計算[J];中國水運(學術(shù)版);2007年04期

8 劉元丹;劉敬喜;譚安全;;單點系泊FPSO風浪流載荷下運動及其系泊力研究[J];船海工程;2011年06期

本文編號：1565919