From the Engineering Reference, the following algorithms will account for surface tilt when calculating exterior convection coefficients:

• TARP (Thermal Analysis Research Program)
• Adaptive Convection Algorithm : this uses both the Emmel and Blocken methods that you mention

These algorithms can be used by adding a SurfaceConvectionAlgorithm:Outside object to your input file. Without this object, EnergyPlus will use the DOE-2 algorithm by default.