Directionally solidified porous materials could be used to replace the water-cooled cooper walls in arc heaters，by which the enthalpy of the gas flow and the heat efficiency could be improved，and thus has a wide application prospect.In this paper，a mathematical model is developed for the heat transfer in unidirectional porous materials contacted with electric arcs.Numerical simulations are carried out to study the effects of porosity，aperture diameter，entry angle，and injection rate on the cooling performance of directional porous materials.The results indicate that the heat flux of the inner wall decreases by 92% with the increase in the porosity from 7.9% to 26.7%.When the porosity and flow velocity are constant，the average temperature of the inner wall increases from 498 K to 697 K with the increase in the aperture diameter from 0.3 mm to 0.8 mm.The variation of the entry angle could affect the injection rate and heat flux of the inner wall，and then change the cooling performance of the directional porous material.In addition，the increase in the injection rate from 14.2% to 42.7% could decrease the heat flux of the inner wall by approximately 17%.The results provide a reference for the application of unidirectional porous materials in arc heaters.