Enhancement of heat transfer and flow drag in roughened rectangular passages

The enhancement of heat transfer and flow drag in rectangular passages with transverse or inclined ribs is analyzed. Experimental data on local heat-transfer coefficients at the middle wall and at the corner of roughened rectangular passages wre correlated, and the expression for resistance factor in test passages was obtained. In the case of a given h/de, the optimum region of the value s/h for heat transfer was also provided. Experimental results show the performance of heat transfer in passages with transverse ribs is higher than that in the passages with inclined ribs at the same h/de and s/h.