Vol.:(0123456789) 1 3 Environmental Earth Sciences (2018) 77:776 https://doi.org/10.1007/s12665-018-7967-4 ORIGINAL ARTICLE Numerical modeling of sediment scouring phenomenon around the ofshore wind turbine pile in marine environment O. Aminoroayaie Yamini 1  · S. Hooman Mousavi 1  · M. R. Kavianpour 1  · Azin Movahedi 1 Received: 5 May 2018 / Accepted: 17 November 2018 © Springer-Verlag GmbH Germany, part of Springer Nature 2018 Abstract In recent years, with daily progress in technology, application of wind turbines for energy generation has become common all around the world. Installation of these turbines at sea encountered a great deal of challenge. One of the most important challenges is scouring around the piles of these turbines due to sea waves and current interaction. Many studies have been conducted in this respect; however, the results are insufcient, and the phenomenon remains poorly understood in tripod wind turbines. In this work, an attempt is made by combining the waves and currents, and changing the substructure of the turbine and the type of the bed materials, to extend the investigation of this phenomenon. The current research is focused on presenting the trend of changes in the amount of scouring. By changing the conditions (including variation in the wave height, variation of the current velocity, variation of the pile diameter, and variation in the size of bed particles), one can arrive at an appropriate estimate and prediction of the shape and the depth of the scour pit. Keywords Wind turbine · Sediment scour · Waves · Current Introduction After becoming industrialized, humans have utilized new energy sources. Wood, coal, oil, and gas have been among the primary energy sources; however, advancements in the new energies’ science, such as nuclear energy, have emerged. All these energy sources are fnite; thus, unlimited energies or, in other words, the renewable energies such as the solar energy are welcomed. One of the novel methods is the use of wind energy which has been utilized in many countries of the world including The Netherlands, Denmark, Britain, etc. The method used in this way includes turbines with great heights installed against the wind direction and the wind energy causes rotation of the turbine blades whose rotation provides the needed energy. Nevertheless, use of this method has some disadvantages. Wind farms need large spaces, and this becomes problem- atic for small countries like The Netherlands. In addition, rotation of the turbine blades and the nearby power plants produce noise which could create problems for the neighbor- ing inhabitants. After many discussions and research works, ofshore wind turbines became the focus of attention. Installation of turbines at sea does not occupy land, the noise produced is outside of the urban environments, and they would not endanger the lives of the neighboring inhabitants. Perhaps, the most important issue is the wind which is up to 20% stronger in the marine environment and this makes it an ideal place for turbine installation. Nevertheless, installation of the turbines at sea is not an easy task. Transport of the long piles and gigantic turbine blades needs special operations. Also working in the marine environment doubles the hardship of work. The major prob- lem is to fnd an appropriate land for installation of the tur- bine and precise design of the turbine pile according to the regional conditions. In addition, the efects of sea waves and currents on the foundation and the installed turbine pile are another issue associated with working in the marine envi- ronment. The waves create vorticity around the turbine’s pile and cause scour of the soil around the pile and make it unstable. Scour around the turbines piles is a serious issue in relation to the ofshore wind turbines. * O. Aminoroayaie Yamini o.aminoroaya@mail.kntu.ac.ir 1 Faculty of Civil Engineering, K.N. Toosi University of Technology, Tehran, Iran