Fully Automated Ship Resistance
Prediction sing the Naval Hydro Pack
Inno GATIN
a,1
, Vuko VUK
ˇ
CEVI
´
C
a
, Vanja
ˇ
SKURI
´
C
a
, Hrvoje JASAK
a
a
Faculty of Mechanical Engineering and Naval Architecture - University of Zagreb,
Croatia
Abstract. A numerical environment for efficient assessment of ship resistance us-
ing CFD is presented in this paper. Predicting ship resistance in calm water with the
Naval Hydro Pack can be performed within a few hours, including grid genera-
tion, computation and post–processing of results. Being able to rapidly predict ship
resistance renders CFD a cost-effective design tool, since a hull form designer can
evaluate multiple variants of hull geometry quickly. The process of setting up, run-
ning and post-processing is accelerated by automating the process to a high level,
significantly decreasing the number of manual work effort. In this paper the capa-
bilities of the Naval Hydro Pack are demonstrated by calculating steady resis-
tance for three different benchmark hull forms, where time for pre-processing, pro-
cessing and post-processing is reported. On average, it took two and a half hours to
obtain steady state results per hull form, including set–up, computational time and
data analysis. Results are validated against available experimental data showing
accuracy with errors below 4%, which is acceptable for early design stage.
Keywords. Steady Resistance, Computational Hydrodynamics, CFD, Naval Hydro
Pack
1. Introduction
This paper presents a highly automated procedure for assessing ship resistance in calm
water using Finite Volume (FV) based CFD. Naval Hydro Pack based on open–source
foam-extend [1] software is used as the CFD module, while cfMesh [2] is used for au-
tomatic grid generation. Python based top–level algorithm is used to automate the proce-
dure from input geometry to result post–processing. High level of automation reduces the
number of man–hours, while the efficiency of the code keeps the required computational
resources at a low level. With a capable CFD engineer, ship resistance can be assessed
accurately in two to three hours in total, taking as low as one man–hour for set–up and
post–processing. Hence, the numerical framework provides highly efficient ship design
tool, allowing multiple hull forms with high–fidelity performance assessment in the early
design stage.
The numerical environment is demonstrated by performing resistance calculations
for three benchmark ships with available experimental data. The three benchmark hull
forms are: KCS (KRISO Container Ship), JBC (Japan Bulk Carrier) and DTMB (David–
1
Corresponding Author: Inno Gatin, Faculty of Mechanical Engineering and Naval Architecture - University
of Zagreb, Croatia; E-mail: inno.gatin@fsb.hr
U
Technology and Science for the Ships of the Future
A. Marinò and V. Bucci (Eds.)
IOS Press, 2018
© 2018 The authors and IOS Press. All rights reserved.
doi:10.3233/978-1-61499-870-9-256
256