Data for: Simultaneous separation of travel-dependent drag and added-mass coefficients for underwater manipulators

This dataset contains processed research data supporting the manuscript “Simultaneous separation of travel-dependent drag and added-mass coefficients for underwater manipulators.” The study tests whether the transient drag coefficient Cd and equivalent added-mass coefficient Cm can be represented primarily as functions of nondimensional travel S/d and separated simultaneously from sectional hydrodynamic-torque data. The torque data were obtained from three-dimensional unsteady CFD simulations of a 4-m cylindrical manipulator link undergoing twelve standard accelerate–cruise–decelerate motions with different angular velocities and accelerations. The files contain smoothed Fluent total-torque histories and Tecplot ten-segment and total-torque histories. These data were processed by binned least-squares coefficient separation and physically constrained piecewise-cubic spline fitting. The coefficient-identification data include combined least-squares samples, separate Cd and Cm scatter-point datasets, spline control points, and densely sampled Cd(S/d) and Cm(S/d) curves. Twelve leave-one-out datasets are provided, each containing samples, control points, and spline curves obtained after excluding one standard case, together with an error summary. The package also contains processed time-series data for seven realistic quintic-polynomial motions covering slew angles of 15–120 degrees and durations of 5–10 s. The files provide time, S/d, angular displacement, angular velocity, angular acceleration, CFD torque, spline-model torque, and error statistics. Results for an optimal constant-coefficient baseline, curve-inflection source tables, and selected auxiliary motion workbooks are also included. The data can be used to reconstruct the identified coefficient curves, inspect sectional and total torque histories, compare the spline model with CFD, assess sensitivity to individual training cases, and recalculate the reported errors. They show systematic variation of both coefficients with S/d and support evaluation of the model’s predictive behavior. File contents, variables, units, provenance, folder structure, and checksums are documented in the README and manifest files. This repository contains processed data only. Water-tank experimental data, the main cone, orbital, two-link, and attached-cylinder spatial-motion datasets, and mesh-convergence source data are not included. Source code, Fluent UDFs, and patent-related implementation files are unavailable because the method is associated with a pending patent application. Raw CFD fields, meshes, and large Fluent case/data files are excluded because of their storage requirements.