Evaluation of wind loads on ships by CFD analysis

Effect of wind loads on marine structures and ships has to be considered during design. Static and dynamic effects of wind forces and moments are incorporated into the rules and regulations of governing authorities by various means. The weather criterion of IMO, part of the mandatory requirements of 2008 IS Code, considers the effect of wind and waves on stability of ships and has been in use for a long time. The criterion is simply based on static heel angle due to pre-defined wind pressure and moment balance concept with respective roll motion. There has been a lot of criticism about the assumptions and therefore validity of the criterion especially for the standard wind pressure of 504 Pa and linear distribution of heeling arms curve irrespective of heel angles. This paper deals with these questionable issues of the weather criterion. CFD analyses have been conducted on several different type of vessels in order to predict the wind forces. The results are then compared with those mandated by various criteria.