|
Converting the Kinetic and Potential Energies in Deep Ocean Waves to determine how much heat you can get from Friction Boilers Calculating the True Power in deep oceanic waves. Assuming a perfect sinusoidal oceanic wave, one metre high between crest and trough with a period of 10 seconds in deep water, its velocity is calculated using the formula (gT/2π) = 15.613 m/s The wavelength, λ vT (gT^2/2π) = 156.131 m The potential energy passing per unit time, per unit length, is Ppotential =m*gh/T where m* is the mass per unit length and h is the change in height at the centreline of the sinusoidal mass of seawater. The cross-section area of the wave’s amplitude is calculated using the following formula Area (2 x base x height)/pi, (2 (λ/2) a)/ π because a h/2 this can be rewritten as (λh/2π). Ppotential =m*g h/T (2 λ h g h ρ) / 4 π T (λ h^2 g ρ) / 2π T and because λ/T is velocity, substituting we get, Ppotential = h^2 g ρ v / 2π (1 x 1 x 9.81 x 1025 x 15.613)/ 2π 24.986kW/m The potential and kinetic energies in waves are exactly equal. I now will calculate the kinetic energy of deep water dispersive waves independently to see if the answers are the same. P kinetic = ½ m v^2 (kW/m) The simultaneous vertical descending and ascending velocity of all oceanic waves irrespective of their height is always √2 (m/s) which I will call vd and va respectively. Substituting we get P kinetic = ½ [(vd h)(va h)(g v ρ)]/2π (kW/m) = ½ [(√2 h) (√2 h) (g v ρ)]/2 π (kW/m) = ½ 2h2 g v ρ)/2 π (kW/m) Therefore, P kinetic = (h^2 g v ρ)/2π (kW/m) = 24.986 (kW/m) = P potential P potential + P kinetic =24.986 + 24.986 = 49.972 kW/m Therefore, P potential + P kinetic = (h^2 g v ρ)/ π (kW/m) so that for all deep pelagic ocean waves the following formula is true; Ptotal = (h^2 g v ρ)/ π Copyright Andrew H Mackay There is no Encyclopaedic Content from third party sources.
|
|
|