الفهرس 
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Abstract
This work is concerned with the numerical and experimental investigation of heat transfer
enhancement and pressure DROP penalty inside corrugated passages. The investigation was
evaluated for number of dimensionless corrugation pitches, related to passage height, 1.5, 2.0 and
3.0, and for number of dimensionless corrugation rib height, related to passage height, 0.05, 0.1
and 0.15, at Reynolds number range 5000<Re<35000.The predicted and experimental results
were compared together to validate the present model.
The discretization technique, based on finite volume method, was used to solve the governing
equations and predict the flow and thermal fields through k−e model in both high Reynolds
number, (HRN), and low Reynolds number, (LRN). The HRN k −e model was used in case of
flow core treatment, while LRNk −e model was used as near wall treatment. The predicted
analysis illustrated that the corrugated ribbed geometry enhanced the heat transfer as well as it
increased the pressure DROP due to the boundary layer breakdown, flow reattachments, and the
flow recirculation downstream the corrugation ribs. The average Nusselt numbers values inside
corrugated ribbed passage were varied between 2.0 and 7.0 times higher than the corresponding
flat passage. Nusselt number in corrugated ribbed passage increased with increase in the
corrugation ribs height and with decrease in the corrugation ribs pitch. Friction factor in
corrugated ribbed passage was higher than that of flat passage by about 2.0 to 6.0 times, and it
increased with increase in corrugated ribs height and with decrease in corrugated ribs pitch. The
thermohydraulic performances factor of corrugated ribbed passage had been found between 0.85
and 1.32.
The best corrugation geometry, to achieve optimum thermohydraulic performance had been
found at corrugation ribs pitch to corrugation ribs height ratio P e between 8.0 and 12.0, while
the optimum Re number range which gives the best thermohydraulic performance was found
between 7000.0 and 13000.0.
The comparison of the experimental results with the numerical results and with some results of
other publications shows that the numerical model satisfies its objective.