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Part I of this two-part paper presents benchmark CFD validation force/moment/motion measurements for surface combatant 5415 in planar-motion-mechanism (PMM) maneuvers. The experiments are conducted in the IIHR towing tank as part of an international collaboration for development/application of uncertainty analysis procedures and assessment of scale effects and facility biases. Stationarity and normality tests and statistical convergence errors, single and multiple run methods for obtaining the maneuvering mathematical model hydrodynamic derivatives, and the effects of heave, pitch and roll motions and fixed/free mount conditions are assessed. Assessment of the methods for obtaining the hydrodynamic derivatives is based on reconstructions of the measured force and moment time histories. Part 2 presents phase-averaged stereo PIV flow field measurements. The data is used as a test case at the SIMMAN 2008 and 2014 workshops on verification and validation of ship maneuvering simulation methods. navigational safety and the development of International Maritime Organization Standards forShip Maneuverability (Resolution MSC.137(76), IMO 2002) has significantly increased its importance. Maneuvering simulation methods have been largely system-based approaches using maneuvering mathematical models and experimental data for estimating the hydrodynamics derivatives since surge, sway, yaw and roll are of primary importance and require viscous effects, whereas heave and pitch are of secondary importance and can be predicted using inviscid methods.Recently, CFD methods have shown great promise for replacing experimental data for estimating the hydrodynamics derivatives and for free running simulations at both model and full scale. Significant progress has been made toward this goal by using Reynolds-averaged Navier-unsteady RANS (URANS)-, or Detached Eddy Simulation (DES)-based codes for various hull forms in captive or free-running maneuvers. A few of the latest examples include steady-drift or -turning simulations by Tahara et al. (2002) for Series 60, Simonsen and Stern (2005) for Esso Osaka, Hyman et al. (2006) for Athena R/V, Bhushan et al. (2011) for naval combatant 5415, and Xing et al. (2012) for a tanker hull form. Dynamic captive-maneuvering simulations were done by Cura Hochbaum (2006) for a twin-screw ferry, Di Mascio et al. (2007) for a tanker, Simonsen et al. (2012) for a container ship, and Sakamoto et al. (2012a,b) for a naval combatant. Free-running simulations such as turning circle or zigzag maneuvers have been done by Bhushan et al. (2009) and Carrica et al. (2013) for a naval combatant and Dubbioso et al. (2012) for a twin-screw tanker. Free running CFD simulations with system identification have recently shown promise for the best and most efficient approach for estimating the hydrodynamic derivatives (Araki et al., 2012). Current CFD research focuses on maneuvering in waves (Sadat-Hosseini et al., 2014) and capsize (Hosseini et al., 2011). The 24 th -27 th International Towing Tank Conference (ITTC) Maneuv...

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Part II of this two-part paper presents CFD benchmark local flow field measurements for a surface combatant in dynamic planar-motion-mechanism (PMM) maneuvers. Phase-averaged stereoscopic particle-image-velocimetry (PIV) measurements are performed for pure sway and pure yaw maneuvers. The geometry is DTMB model 5512, a 3.048 m geosim of DTMB model 5415. The experiments aredone in a 100 m × 3 m × 3 m towing tank. The measurement system is a custom-designed towingtank maneuvering test flow-mapping system, which features a PMM for captive model testing with an integrated stereoscopic PIV. Statistical convergence error is defined and monitored by using the confidence intervalsof the mean and variance. The quality of data is also assessed by following standard uncertainty assessmentprocedures.The present experimental dataare cross-referenced with computational simulations for identification of the major vortices in the flow. The core locations and trajectories of the major vortices are traced and the flow variables at the core locationsare analyzed.The tests of both Parts I and II are sufficiently documented and detailed to be useful as experimental benchmark data for validation of computational fluid dynamicscodes.Part I presents the force/moment/motion measurements.