TY  - JOUR
T1  - Computation of Steering and Braking Forces of Tractor  Type Escort Tugs
AU  - Aydın, Çağrı
AU  - Karabulut, Utku Cem
AU  - Ünal, Uğur Onal
AU  - Sarıöz, Kadir
PY  - 2017
DA  - December
JF  - Gemi ve Deniz Teknolojisi
JO  - GDT
PB  - TMMOB Gemi Mühendisleri Odası
WT  - DergiPark
SN  - 1300-1973
SP  - 21
EP  - 36
IS  - 210
LA  - tr
AB  - This paper presents two practical computational proceduresto predict the steering and braking forces applied by tractor type escort tugsto large vessels, particularly oil tankers. The essential part of the escortperformance prediction methodology is the computation of hydrodynamic forcesgenerated by the tug’s hull and the appendages such as skeg. These forces canbe converted into the steering and braking force components which define theescort performance of the tug. The hydrodynamic forces can be estimated byscaled model tests however this approach is not suitable for early designstudies because of cost and time restrictions. The first methodology presentedin this paper is based on semi-empirical methods, obtained from model testmeasurements and full-scale test results, and developed in order to be used atearly design stages where limited design information is available. Acomputational technique based on Reynolds-Averaged-Navier-Stokes (RANS)equations is recommended for the later stages of design process in which moreprecise definition of hull and appendages geometries are available. Thisapproach, which takes local flow characteristics into account, can be used forthe optimisation of hull and appendages geometries. In this study, two differentapproaches are presented and used on a given escort tug.
KW  - Escort Tug
KW  - Hydrodynamic Forces
KW  - RANS
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UR  - https://dergipark.org.tr/tr/pub/gdt/issue//379742
L1  - https://dergipark.org.tr/tr/download/article-file/405679
ER  -