Experimental research of highly viscous fluid cooling in cross-flow to a tube bundle

The paper deals with the results obtained during experimental research of the heat transfer performances of cross-flow heat exchanger with highly viscous fuel oil flowing normal to the tube bundle with Re < 1 and Pr ∼ 2000. Experimental research was performed on the oil cooler that consist of 50 in-line, with 10 mm outside tube diameter, 100 mm tube length, with both longitudinal and transversal tube pitch of 19.5 mm. Comparison of experimental results with equations from literature sources showed that dispersion of measured and calculated values is significant. In order to obtain more accurate equation statistical analysis was performed and dimensionless equation in the formNuD=3.17·ReDc0.1·Pr1/3·PrPrw0.25is obtained. Similar form of equation can be obtained when Reynolds–Colburn analogy is applied on previous experimental research of pressure drop.