Investing the Influence of Ship Wake Velocities in Waves Considering Ship/Hull Interactions to Propeller Performance and Unsteady Forces(II)

瀏覽統計 Email 通知 RSS Feed

簡歷

基本資料

Project title

Code/計畫編號

MOST109-2221-E019-018

Translated Name/計畫中文名

由分析船舶運動時與螺槳互動之艉跡流探討其對於螺槳性能與非定常受力之影響(II)

Project Coordinator/計畫主持人

Ching-Yeh Hsin

Funding Organization/主管機關

National Science and Technology Council

Department/Unit

Department of Systems Engineering and Naval Architecture

Website

https://www.grb.gov.tw/search/planDetail?id=13543092

Year

2020

Start date/計畫起

01-08-2020

Expected Completion/計畫迄

31-07-2021

Bugetid/研究經費

1044千元

ResearchField/研究領域

機械工程

所提出之計畫，主要目標是希望藉由分析船舶運動時與螺槳互動的船艉跡流，了解其組成的成分，並進一步探討其對於螺槳性能的影響。而完成這些探討後，最終是希望提升螺槳於波浪中的性能。所提之計畫對於靜水與波浪中船舶與螺槳互動的計算，將應用三種不同的方法，Phase I方法應用黏性流對疊船模方法計算船舶與螺槳互動之阻力，勢流興波阻力程式計算興波阻力，波浪附加阻力也應用勢流方法進行計算。Phase II方法(或是“固定法”)應用黏性流方法計算船舶與螺槳互動之阻力以及興波阻力，波浪附加阻力仍然應用勢流方法進行計算。此方法中，波浪中的自推僅加上波浪附加阻力進行力的平衡計算，而不考慮船舶運動，也就是，船舶事實上是固定住，不隨來波運動的。Phase III方法(或是“運動法”)則完全應用黏性流RANS方法進行計算，船舶會隨來波而運動。本計畫的自推模擬將應用體積力的方法，以體積力的形式代表螺槳的受力。在過去主持人相關的研究中，比較重視力的計算，以及計算方法的建立與確認，而所提出的此計畫中，將著重於艉跡流的細節流場分析，藉由不同計算方法的差異，試圖了解以下的主題：一是在波浪中沒有螺槳運作時的波浪誘導速度與有螺槳運作時的波浪誘導速度之間的差異，以及不同螺槳負荷的影響。二是考慮船舶運動時，船舶運動在不同狀況下所誘導的速度為何，例如螺槳的不同負荷，不同波長的來波，以及節能裝置以及船型的影響。三則是這些誘導速度，黏性與勢流的效應又各自為何。本計畫預期兩年完成，應用的計算案例包含貨櫃輪KCS、具節能裝置貨櫃輪P-Hull、大型油輪KVLCC2，以及散裝貨輪JBC於靜水中與來波中的自推計算與跡流分析。KCS並考慮不同波長來波中的自推計算與跡流分析。 In this proposed project, the analysis of ship wake at propeller plane in ship motions will be carried out to understand its components. Once the components are clarified, their contributions to the propeller performance and propeller unsteady forces can be investigated. Three different approaches will be adopted for this project. For the first approach (Phase I), the RANS method is used for computing the viscous hull drag, and potential flow methods are used for both wave-making resistance and wave added resistance computations. For the second approach (Phase II，or “Fixed method”), RANS method is used for computing the hull drag in calm water, and potential flow methods are used for wave added resistance. In this method, the self-propulsion in waves is carried out only by considering the wave added resistance, but not considering the ship motions, that is, the ship is not moving with the incoming waves. For the third approach (Phase III, or “Moving method”), only the viscous flow RANS method is used for computations. In the “Moving method”, the ship will move with the incoming waves. The body force method is used to represent the propeller effects. In the previous researches carried out by the principal investigator, the focuses are on the force balance in self-propulsion and establishment of the computational methods. In this proposed project, the focus will be on the wake velocities. The computed velocity differences by different approaches will be analyzed to understand the following topics. First, the difference between the wave induced velocity in waves with and without a propeller, and the influence of the propeller loadings. Secondly, the velocities induced by ship motions at different conditions, such as different propeller loadings, different wave length and effects of energy-saving devices and ship types. Finally, the viscous and potential effects of these velocities. This is a 2-year project, and the wake analysis cases include self-propulsions of different ships in calm water and in waves. These ships include the container ship KCS, the containership with an energy-saving device P-Hull, the large tanker KVLCC2, and the bulk carrier JBC. For the computations of KCS, different wave length will also be considered.

Keyword(s)

螺槳
自推試驗
艉跡流
船舶運動
邊界元素法
RANS
體積力
propeller
self-propulsion test
ship wake
ship motion
Boundary Element Method
RANS
body force

DSpace CRIS

Investing the Influence of Ship Wake Velocities in Waves Considering Ship/Hull Interactions to Propeller Performance and Unsteady Forces(II)

基本資料

Description