A Practical Approach for Design of Marine Propellers with Systematic Propeller Series
Original scientific paper Although there have been important developments in marine propellers since their first use in 1850, the main concept has been conserved. Parallel to the developments in the computer technologies in the past 50 years, methods based on the circulation theory are often used for the design and analysis of propellers. Due to the ability to predict the propulsion performance with just a few design parameters, the use of systematic propeller series based on open water model experiments is still widespread. The design with standard propeller series is usually made with diagrams developed from model experiments. Reading errors during the use of these diagrams are inevitable. In the presented study a practical approach is developed for preventing reading errors and time loss during the design with standard propeller series. A practical approach based on empirical formulas for the design and performance prediction for four-bladed Wageningen B propeller series is presented, and design applications for three propellers with different loading conditions are realized. The results obtained from the presented method are compared with those of open water diagram data and a good agreement between the results is observed.
ANALISA NILAI MAXIMUM THRUST PROPELLER B-SERIES DAN KAPLAN SERIES PADA KAPAL TUGBOAT ARI 400 HP DENGAN VARIASI DIAMETER, JUMLAH DAUN, SUDUT RAKE MENGGUNAKAN CFD
Aspek yang paling penting dalam pembuatan kapal itu sendiri ialah aspek perencanaan dibidang sistem propulsi. Adapun aspek dari sitem propulsi itu sendiri ialah Perencanaan desain Propeller. Propeller merupakan salah satu aspek yang wajib direncanakan dengan baik guna mencapai tujuan fungsi kapal dalam hal kecepatan. Kecepatan pada kapal tidak terlepas dari desain propeller yang baik agar mendapatkan gaya dorong (Thrust) optimal yang dihasilkan oleh gerak propeller.Tujuan dari penelitian ini adalah untuk mengetahui nilai thrust optimum untuk Propeller TB Ari 400 HP dari analisa model variasi yang dibuat sehingga dapat mengetahui dari model tersebut manakah yang memiliki nilai thrust tinggi dan torque terendah serta untuk mengetahui perbandingan nilai Thrust yang dihasilkan dari variasi model Fpp B-series dan Fpp Kaplan Series dengan variabel variasi diameter, sudut rake dan jumlah daun. Hasil dari penelitian ini menunjukkan Nilai thrust tertinggi dihasilkan pada model Propeller Ka5 50 Series diameter 1m sudut rake 0 0 dengan nilai thrust tertinggi sebesar 14608,8 N pada putaran 500 RPM. Nilai torque terendah dihasilkan pada model Propeller B4 50 Series sudut 10 0 diameter 0,813m dengan nilai 513,967 Nm pada putaran 500 RPM. Nilai perbandingan thrust dan torque tersebut  di dapatkan dari model dengan parameter analysis dimensi yang sama dan Putaran 500 RPM. Dan mendaptkan Nilai efisiensi tertinggi diperoleh pada model propeller b4 50 sudut rake 12 0 diameter 0,813m yaitu sebesar 0,6764 pada putaran 500 RPM
Accurate measurements of output characteristics and detonations of motorbike high-speed racing engine and their optimization at actual atmospheric conditions and combusted mixture composition
Abstract At a motorbike high speed racing engine there is very important an output engine characteristics which depends significantly on a detonation combustion rate, atmospheric conditions and a combusted mixture composition. The combustion process has got a relevant influence on a wear degree of main engine parts or on their damage eventually. The detonation combustion rate is very important because this kind of burning can be not only destructive but a useful phenomenon, as well. If the process of detonation burning is kept on a certain level, it can help significantly to the next increasing of an engine power output. In this article there is described the measurements of output characteristics of a high-speed racing engine which were performed by means of a data-recording system and the detonation combustion was evaluated using a quantitative method. The actual values of atmospheric conditions and the mixture composition were added to the measured values. Then the obtained values are compared visually with a damage degree of an engine piston caused by the detonation burning. The result is a limit value expressed in a number of detonation units related to a run distance interval of the vehicle driven by the high-speed racing engine. In framework of this run distance interval there is the process of detonation burning profitable. As well as it increases an engine power output and together it is not destructive with regard to engine design parts.