by Stevens Institute of Technology .
Written in English
Thesis (MS)--Stevens Institute of Technology, 1955.
for the lift of flat planing surfaces are reviewed, and the resemblance of the planing surface to the airfoil noted. A simple expression, which con- verges to the correct limits for exactly known cases, is assumed for the ratio of planing to air- foil lift, and the planing lift is then estimated by using airfoil experimental data. The resultingCited by: 1. The slope of the straight portion of the curve is the two-dimensional lift-curve slope, (d C L ∕ d α) ∞, or a ∞. Its theoretical value for a thin section (strictly a curved or flat plate) is 2 π per radian (see Section ). For a section of finite thickness in air, a more accurate empirical value is. Weight of a planing hull is supported by the lift force which consists of two terms; hydrodynamic and hydrostatic terms. Lift coefficient, based on the beam squared, is denoted by LC and lift coefficient, based on the bottom area, is denoted by CL,S. These coefficients are obtained from equations () and () (Morabito (). () V b. The modern lift equation states that lift is equal to the lift coefficient (Cl) times the density of the air (r) times half of the square of the velocity (V) times the wing area (A). L.5 * Cl * r * V^2 * A.
Anthony F Molland, Stephen R Turnock, in Marine Rudders and Control Surfaces, Evaluation of influence coefficients. At the heart of a lifting surface panel method is the efficient calculation of the potential (or velocity) influence coefficients at a field point due to a particular panel's source or dipole distribution. Newman derived expressions  for calculating the. where 0 is the lift coefficient of planing plate at. Numerical results of a planing flat plate and planing craft model are presented. different planing surfaces were compared in the. This last example demonstrates the point that beam of the planing surface is a far greater contributor to dynamic lift than waterline length. This follows in the same way that the luff length is more important in determining aerodynamic lift of a sail than the chord of the sail. The lift curve slope of a flat plate is the same as that of regular airfoils, complete with stall. They have a zero-lift angle of attack of 0° (obviously) and separated flow on the suction side. The maximum lift coefficient of to is reached at moderate angles of attack - details depend on the aspect ratio.
at an angle of attack ~ a formula for the two-dimensional lift coefficient may be found from Ref. 8" 2~ cos CLo cot ½c¢ cos ~ -- tan ½~ log (½ -- ½ cos ~) + ~ -- z¢ -- sin ~ (9) Consider a finite beam flat-plate planing as in Fig. 2. The lift on the plate may be supposed. The normal force coefficient on a flat planing surface having arbitrary heave and pitch motion in two-dimensional flow is compared with the lift coefficient of a thin wing in an infinite fluid. Here's an example of calculating the lift coefficient, using real-world data from a Boeing Its lift generated is , lb; air density is slug/ft 3 (assuming an altitude of 40, ft); the velocity is ft/s; and the reference area is 5, ft 2. Inserting all of that into your equation for lift coefficient gives you. q Re rLE FIN rNOSE S STT SCA SFIN SHT SREF SVT SWET (SWET)F] \C/BOD1 Y V/FIN ILE w,GTO y a dynamic pressure, lb/ft2 Reynolds number fin leading-edge radius, ft nose radius, ft plan form area, ft2 maximum cross-sectional area, ft2 canard planform area, ft2 fin planform area, ft2 total horizontal fin planform area, ft2 reference area used in aerodynamic coefficients (body planform area), ft2.