A numerical method for simulating three-dimensional laminar forced convective heat transfer in a horizontal passage with trapezoid cross section under uniform heat flux condition was presented. The results presented cover structure parameter b/a range of 1/4~4/3, and included angle of bottom side θ range of 60°, 75° and 85°. The developments and distributions of heat transfer and flow fields, and the average Nusselt numbers at different axial cross-sections in the horizontal passage with trapezoid cross section were discussed when three walls of passage were heated and bottom wall was insulated. In addition, the results were compared with those of four walls heated. The results show that the temperature distribution, convection heat transfer performance and the effects of structure parameters for a passage with trapezoid cross section and three walls heated are different from those with four walls heated. 

Laminar forced convection,   ,  Passage with trapezoid cross-section,   ,  Thermal-dynamic performance,   ,  Numerical simulation