Comparative investigation of the stagger variation influence on the hydrodynamic interference of high speed trimaran

• Main Authors: K.A. Hafez, A.A. El-Kot
• Format: Article
• Language: English
• Published: Elsevier 2012-09-01
• Series: Alexandria Engineering Journal
• Subjects: High speed trimaran (HST); Hydrodynamic interference factor (HIF); Calm water resistance of trimaran; Stagger of outriggers; Wigley©-st model; AMECRC©-09 model; NPL©-4a model
• Online Access: http://www.sciencedirect.com/science/article/pii/S1110016812000154

This paper numerically investigates the influence of stagger variation of the outriggers on the hydrodynamic interference of high speed trimaran (HST). The slender body method (SBM) embedded in the Hullspeed© [1] module of the Maxsurf© [2] package is used for calculating the resistance of three symmetric trimaran series moving in a calm free surface of deep water. Each individual trimaran series comprises of 4681 configurations generated by considering 151 staggers covering the interval (−50% ⩽ α ⩽ +100%), and 31 separations covering the interval (100% ⩽ β ⩽ 400%) for 81 Froude numbers covering the interval (0.20 ⩽ Fn ⩽ 1.0). In developing the three trimaran series, Wigley©-st [3], AMECRC©-09 [4,5], and NPL©-4a [6,7] models are used separately for both the main and side hulls of each individual series models. Seeking automation, a computer macro-named Tri-PL© is developed from scratch based on the Visual Basic for Applications© [8] programming language. To generate each model of the individual series together with its detailed hydrostatic particulars, Tri-PL© automatically interferes the Maxsurf© [2] module. To calculate the resistance components together with the associating wave pattern for each model of the individual series, Tri-PL© automatically interferes the Hullspeed© [1] module. To benchmark Tri-PL© macro-together with the mathematical procedures embedded therein, and to rely on the analysis outcomes, the numerical results of both Wigley©-st [3] and AMECRC©-09 [4,5] models are validated. To visualize the significant data of the analysis properly, a graph template of the SigmaPlot© [9] is created to read the numerical results of the Tri-PL©, and then automatically prepares all the necessary analysis graphs.