Latent heat release relates to several factors, such as heat and solute mass transfers in the solidification process, in which strong nonlinear couplings among the temperature, solid fraction and liquid concentration (T-fs-CL) inherently exist. A previously proposed numerical iteration method, based on the continuum model of solidification transport phenomena (STP) and temperature compensation method, is used to further investigate the latent heat release problems in alloy solidifica-tions of any temperature range, including the case at a fixed solidification temperature. The method is applied to the STP-based numerical simulations for 2D Al-Cu blade-like castings of different nominal compositions and different solid back-diffusion effects. The validity and efficiency of the present method are demonstrated by the sample computations of several typical solidification cases from Scheil-type continuously to Lever-Rule model and of nine nominal compositions from almost zero to nearly the alloy's eutectic composition. The numerical method is confirmed by the 3D STP-based simulations for the directional solidification processes of real blade castings. The computation results show both the efficiency of the numerical iteration method and the remarkable influences of the casting shape on the solidification transport processes.