The course presents the fundamental knowledges about movement and behaviour at sea of monhull fixed keel sailing boats, in order to formulate and develop the design.
Develop the fundamental skills necessary to design sailing boats.
Learning of the physical phenomena which govern the behaviour of the sailing boat; study of the techniques of experimentation and data acquisition (systematic series, wind tunnel, on board measures, etc); methods of design and performance prediction.
Frontal lessons
Design criteria
Definition of main characteristics of the boat
Definition of main dimensions – Statistical data and allotrope boats
Approach to the hull design
Principal softwares used for the development of the design
The naval CADs
The technical specification
Rules
CE Directive 2013/53/UE
Meaning of design categories and navigation limits for “natanti” and “imbarcazioni” flying Italian flag
Directives and harmonised rules
Essential requirements
Rules for the classifications of pleasure yachts with length Lh greater than 24 m
The wind
True and apparent wind
Reaches and tacking
Polar diagram of boat speeds
Surfaces and foils suitable for generate control and power
Fluid dynamic force: lift and drag
Aerodynamic and hydrodynamic forces
Equilibrium
Equilibrium equations
Centre of effort of the submerged part of hull and appendages, CRL
Centre of effort of sails, CE
Balance between centres of effort
Lead of the sail
Balance of the rudder
Stability
Transversal and longitudinal stability at little angles
Dellenbaugh angle and rolling period
Curve of the righting arms
Righting moment in waves
Stability criteria for boats (LH ≤ 24 m) according with european rule ISO 12217-2
Stability criteria for ships (LH > 24 m) according with The Large Commercial Yacht Code (LY3)
Resistance to the motion of the hull
Viscous drag
Wave resistance
The Delft systematic series
Heel resistance
Added resistance
Power of the auxiliary engine
Resistance of the propeller in sail navigation
The appendages: keel and rudder
Flow around a wing
Prandtl’s lifting line theory
Lift and induced resistance of the boat
Winged keels
Canard wings
Tandem keels
Canting keels
Gerritsma e Keuning experiments about interaction between hull and keel
Shape of the section of appendages
Practical design of fins and rudders
Advanced section design
Choose of areas of keel and rudder
Single and double rudders
The sails
The flow around the sail
Shape of the sails
Camber of the sail
Mast interference
Shape of the rigging
Hazen’s model for the aerodynamic of sails and rigging
Motive and lateral power
Statistical parameters of sail plan
Scantling of mast and rigging
Forces on the shrouds
Forces on stays
Choose of cables for shrouds and stays
Mast scantling – Nordic Boat Standard method
Scantling of the boom
Scantling of the spreaders
Holes in the mast
Skene’s method
Components of mast and rigging
Scantling of ballasted keel
Fixed keel at 90° knockdown
Longitudinal grounding
Scantling of ballasted keel according to ISO 12215-9
Scantling of the rudder
Scantling of the rudder according to ISO 12215-8
Scantling of deck fittings
Loads on sheets and halyards
The system of handling of fore sail
The system of handling of main sail
The winches
Notes of fluid mechanic
Bernoulli’s equation
Effect of friction on flow schemes
Circulation and Magnus effect
The Flettner’s rotor
Generation of lift by a wing
Kutta-Joukowsky’s hypothesys
The performance predition
The performance predition softwares
Calculus methodology of VPP
On board plants
Bilge plant
Black and gray waters plant
Fuel plant
Fresh water plant
GPL plant
Appendixes (only for information, not included in the examination program)
Types of sails and rigging
Nomenclature
The waves
L.Larsson, R.Eliasson, M.Orych “Principles of Yacht Design”, 4a ed., International Marine / McGraw-Hill Education, 2014.
C.A.Marchaj, “Aero-Idrodinamica della Vela”, Mursia, 1987
P. E. Liguori, “Le vele”, Hoepli, 2006
R. Garret, “Fisica della vela”, Zanichelli, 1994
I. H. Abbot, A. E. von Doehnoff, L. S. Stivers jr, “Summary of airfoil data”, NACA
Offshore Racing Congress, “ORC VPP Documentation”, ORC 2017
Ricevimento: By appointment (e-mail ponsicchi@ponsicchi.it)
PAOLO PONSICCHI (President)
DARIO BOOTE
Second half-year
Viva voce exam
Registration by Aulaweb, mandatory at least three days before exam.
