抄録
Open characteristics of non-symmetric propeller, which adjacent blade geometries are different, are studied in this paper. Four bladed non-symmetric propeller was designed for 60 type panamax bulk carrier together with three bladed conventional propeller and five bladed conventional propeller such that two large blades of the four bladed non-symmetric propeller absorbed eighty percent of engine output and the other two small blades absorbed twenty percent of engine output. Results of propeller open tests show that efficiency of the 4 bladed non-symmetric propeller is from one to two percent higher than those of the other two propellers. Lifting surface of the four bladed non-symmetric propeller was solved by iteration method. Calculated open characteristics of the four bladed non-symmetric propeller agreed well with the experimental results. Calculation results also show that the small blades contribute to the efficiency increase of the four bladed non-symmetric propeller.
