### Heat Sink Convection with Fins Calculator

 FINS Fins are used to increase heat transfer area and provide a cooling effect. However, if h*A / P*k is greater than 1.00 the fins will insulate and prevent heat flow. h = air film convective coefficient A = exposed surface area of the fins. P = perimeter of the fins. k = fin material conductivity coefficient. Case 1. Fin, finite length, heat loss by convection at end. Heat flow rate,  Q = (K*Ab*n*ΔT)*X1 / X2 Input Data Temperature at fin base,  T1 = deg F Room Temperature,  T2 = deg F Fin width,  w = in Fin thickness,  t = in Fin material thermal conductivity,  K = W/m*C Convective heat transfer coefficient,  h = W / m^2*C Fin length,  L = in Number of fins,  N = Calculations Fin width,  w = m Fin thickness,  t = m Fin base area,  A = w*t m^2 A = m^2 Temperature difference,  ΔT = T1 - T2 ΔT = deg F ΔT = deg C For thin fin,  n = (2*h/K*t)^.5 n = h / n*K = L = m n*L = sinh(n*L) = cosh(n*L) = X1 = [(sinh(n*L) + (h / n*K)*cosh(n*L)] X1 = X2 = [(cosh(n*L) + (h / n*K)*sinh(n*L)] X2 = Q = N*(K*A*n*ΔT)*(X1 / X2)) Answer:  Q = Watts Case 2. Fin, finite length (L) insulated end. tanh(n*L) = Heat flow rate,  Q = N*(K*A*n*ΔT)*tanh(n*L) Answer:  Q = Watts