Keuning hull series

The Keuning hull series is the Delft Systematic Yacht Hull Series (DSYHS), a set of about 70 systematically varied sailing-yacht models tested at the Delft Ship Hydromechanics Laboratory, the work of J. Gerritsma and J.A. Keuning. It is a displacement and semi-displacement yacht series, not a planing series. From the measured bare-hull, heeled, and appendage data Keuning and co-workers built regression formulas for residuary resistance, viscous resistance, and the resistance increase with heel and leeway, which feed velocity prediction programs for sailing yachts. The series parameters span length-displacement ratio, beam-draft ratio, prismatic coefficient, and longitudinal center of buoyancy.