Power by Admiralty Coefficient
Estimate a ship's propulsive power by the Admiralty formula, P = (∆^(2/3)·V³)/C, from the displacement (∆, t), the speed (V, knots) and the Admiralty coefficient (C), characteristic of similar hulls. It is a classic, fast method to predict the required power in the preliminary design stage, based on similarity with existing ships. The V³ dependence shows the high cost of speed. Enter the displacement, the speed and the coefficient C.
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Potência pelo coeficiente do Almirantado
Antes dos métodos computacionais, os projetistas navais estimavam a potência de um navio novo por semelhança com navios existentes, usando a fórmula do Almirantado: P = (∆^(2/3)·V³)/C. O coeficiente C é quase constante para cascos parecidos, então, conhecendo-o de um navio de referência, prevê-se a potência do projeto. Dois detalhes contam a física: o expoente 2/3 no deslocamento converte volume em área (a resistência escala com a superfície molhada), e o cubo da velocidade revela o custo brutal de ir mais rápido — dobrar a velocidade exige oito vezes mais potência. Continua útil hoje como estimativa rápida de anteprojeto. Informe o deslocamento, a velocidade e o coeficiente C.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.