[雙語翻譯]--外文翻譯--一個浮動式海洋平臺的新設計（原文）

1、1 Copyright © 2016 by ASME A NEW DESIGN FOR FLOATING OFFSHORE PLATFORMS S.V. Khonsari, Member, ASME Department of Civil Engineering Sharif University of Technology P.O. Box 11155-9313 Tehran 14588-89694, Iran

2、F: +98-21-8880 3629, E: vaheed_k@yahoo.co.uk G.L. England, Member, ASME Department of Civil & Environmental Engineering Imperial College London London SW7 2BU, UK F: +44-20-7594 5989, E: g.england@imperial.

3、ac.uk E. Moradkhan Department of Civil Engineering Sharif University of Technology P.O. Box 11155-9313 Tehran, Iran E: a.moradkhan@gmail.com A.R. Valikhani Department of Civil Engineering Sharif University of Tech

4、nology P.O. Box 11155-9313 Tehran, Iran E: valikhanialireza@yahoo.com M.R. Bahadori Department of Civil Engineering Sharif University of Technology P.O. Box 11155-9313 Tehran, Iran E: bahadori.mr@gmail.com ABSTRACT

5、 While for shallow waters the use of old offshore jackets still seems efficient and justifiable, for deep and ultra-deep waters such platforms cannot be used. During the past few decades the old generation of fixed

6、offshore platforms was succeeded by the new floating platforms and new designs such as FPSOs. A new family of floating offshore platforms has been developed. These should be able to respond to size, weight and space

7、 for operating equipment, i.e. they can be constructed to have a wide range of load-bearing capacities. Use is made of the old concept of Life Saving Tubes, which in their simplest form can be a toroidal shaped tyre

8、inner tube. The Torus- shaped idea can be further extended to other shapes obtained either by revolving any plane closed curve or poly-line about a coplanar axis which does not intersect it, or by extruding the curve/

9、poly-line through a closed path. The preliminary ‘structural’ calculations carried out on various samples of the torus-shaped members of this family of platforms showed that theoretically they can be designed to carry

10、 as much load as required and provide the users with the required space on the water. Moreover, basic studies of the stability of such systems in water showed their large metacentric heights as well as large righting

11、moment arms, hence their high degree of stability. This stability can be further increased by using other versions of this idea with more efficient toroidal shapes. Furthermore, apparently, much study is required how

12、ever to establish this idea as a viable, cost- effective and efficient alternative for current generations of offshore floating platforms. Keywords: Floating offshore platforms, torus-shaped and toroidal-shaped hulls,

13、buoyancy, metacenter, stability in water. Proceedings of the ASME 2016 31st International Conference on Ocean, Offshore and Arctic Engineering OMAE2016 July 1-6, 2016, Rio de Janeiro, Brazil OMAE2016-83698Downloaded Fr

14、om: http://asmedigitalcollection.asme.org/ on 05/20/2016 Terms of Use: http://asme.org/terms3 Copyright © 2016 by ASME Figure 1- The conceptual design of the proposed floating hull. (a) the original concept with t

15、orus-shaped geometry, (b) an improved design with larger buoyancy force, (c) a torus with triangular cross section, (d) triangular cross section used with triangular plan. Figure 2- A modular (segmental) version of th

16、e devised platform with four constituting segments connected to each other through a truss-type structure. LOAD-BEARING CAPACITY a- Donut-Shaped Hulls In order to have an initial estimate of the load-bearing capacit

17、y of the original version of this type of platform, the following simple basic calculations are presented. Three cases have been studied. 1- Semi-submerged, h=r, (Fig. 3(a)). 2- 3/4 height submerged, h=3/2r, (Fig. 3

18、(b)). 3- Fully submerged, h=2r, (Fig. 3(c)). Buoyancy force, b F (variable for the 3 cases), and the weight of the steel hull, s W (constant for the 3 cases) and hence the load-bearing capacity of either case, C, ar

19、e calculated as below, 1- Semi-submerged hull w w d b R r V F ρ π ρ 2 2 = = (1)s s s s rRt R t r R r W ρ π ρ π ρ π 2 2 2 2 2 4 ) ( 2 2 ≈ ? ? = (2)s w s b r rRt R r W F C ρ π ρ π 2 2 2 4 ? = ? = . (3)2- 3/4 height submer

20、ged hull = + = = w w d b A A R V F ρ π ρ ) ( 2 2 1w r r R ρ α α π πα π π ? ?? ? ?? + 2+ = cos sin ) ( 2 2 2 2 (4)w b r r R F ρ π π π α ? ???? ??? + = → /6 = 2 2 43 ) ( 32 2 (5)s w s b r rRt r r R W F C ρ π ρ π π 2 ? ? ??

21、?? ??? + = ? = 4 43 ) ( 32 2 2 2 5 . 1 . (6)3- Fully-submerged hull w w d b R r V F ρ π ρ 2 2 2 = = (7)s w s b r rRt R r W F C ρ π ρ π 2 2 2 2 4 2 ? = ? = . (8)Downloaded From: http://asmedigitalcollection.asme.org/ on