| Summary: | Possibility of a collision restricts multiple aspects of ship design. An LNG tank must be situated at a fifth of a ships breadth away from the ship side regardless of the ship type. Effects of ship type on collision performance are expected to be relevant and are thus evaluated here with means of nonlinear finite element method (FEM). Application of FEM allows the modelling of elastic and plastic material response with the crucial addition of material failure. Coarse mesh and material failure modelling provide difficulties in the simulation which have been lately researched actively. Background for the material effects are first discussed with the numerical method used to solve the structural responses. Next, constant displacement quasi-static ship-to-ship side collision simulations are performed for three different ship types. The ships in question are an icebreaker, a ropax vessel and a cruise ship. Force-penetration curves are produced for different collision scenarios and the energy spent in these collisions is analysed. Comparison of energy absorption in the collision events is then performed between the ship types. Simulations were conducted successfully and the results confirm the original assumption of ship type effect in collision performance. Icebreaker collision is found to involve similar amount of energy at B/10 level as the cruise and ropax vessels at B/5. The result is of a very relevant scale and for an LNG tank the difference could translate into 33 % bigger tank capacity. For future work the relevant collision scenarios regarding design could be investigated more and the material and fracture models enhanced even further. Törmäyksen mahdollisuus vaikuttaa moniin laivanrakennuksen osa-alueisiin. LNG tankkien tulee sijoittua viidesosan laivan leveydestä etäisyydelle laivan kyljestä riippumatta laivan tyypistä. Laivatyypin oletetaan kuitenkin vaikuttavan oleellisesti laivan suorituskykyyn törmäystilanteessa. Vaikutusta tutkitaan tässä työssä epälineaarista elementtimenetelmää (FEM) hyödyntäen. ...
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