A 1-D mathematical model for boiling heat transfer in the porous wick with channels was developed in an attempt to obtain the structural optimization of the channels. The effect of vapor channels on boil heat transfer was analyzed theoretically. It is shown that the open channels in the porous wick can enhance boil heat transfer and increase the critical heat flux. It is predict from this model, that the dryout conditions are affected by channels size and density. An optional opening density exists, the value of which depends on the specific properties of the porous coating.