Document Type : Original Manuscript

Authors

Mechanical Engineering Department, Abadan Faculty of Petroleum, Petroleum University of Technology, Abadan, Iran.

Abstract

Offshore oil terminals are used as a cheaper and safer solution than shore terminals for unloading and loading tankers. There are different types of offshore terminals. Therefore, comparing the dynamic response of these terminals will be effective in identifying their strengths and weaknesses. The present study is to compare the dynamic response of the structures of three common offshore oil terminals, including CALM, SALM, and CMBM in environmental conditions under the Persian Gulf region. Simulation is used in OrcaFlex software to obtain structural responses including the tension created in the mooring line and hawser, motion the tankers connected to them. The results show that considering the same operating conditions, the maximum tensions created in the SALM terminal mooring are 2.7 and 1.3 times higher than the CALM and CMBM terminals, respectively. Also, the maximum tension in the SALM terminal hawser is 1.5 and 4.3 times higher in the CALM and CMBM terminals, respectively. As the environmental conditions become more critical, the SALM terminal mooring shows the most stability. By increasing the tonnage of the tankers from 45,000 to 320,000 tons, the maximum tension created in the CMBM mooring has the least change; This is while the maximum tension created in the terminal mooring of CALM and SALM increases by 100% and 156%, respectively. Comparing the displacement created in the tankers (during operation), it results that the displacement in the tanker connected to the CMBM terminal has a minimum size and the displacement in the tankers connected to CALM and SALM is almost the same.

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