TY - GEN
T1 - DNS of unsteady heat transfer increase on a curved surface due to wake-induced turbulence
AU - Von Terzi, D.
AU - Venema, L.
AU - Bauer, H. J.
AU - Rodi, W.
PY - 2011
Y1 - 2011
N2 - From experimental studies it is well established that free-stream and wake-induced turbulence can increase the heat transfer on curved surfaces such as turbine blades or cylinders even if the mean flow matches corresponding laminar velocity profiles. Here, preliminary results of an investigation using (embedded) Direct Numerical Simulation (DNS) are reported that aim at identifying the responsible physical mechanisms for this phenomenon. The setup follows an existing experiment where a heated cylinder is subjected to the turbulent wake of a smaller cylinder placed upstream. The Reynolds number based on the diameter of the heated cylinder is Re = 48, 000. A key parameter identified in an experimental correlation is the characteristic turbulence level Tua that includes a dependency on Re and the mean flow acceleration. For the present study, Tua is an order of magnitude higher than those reported in any previous DNS. The obtained Nusselt number is in good agreement with the experimental correlation. More and better resolved data is currently produced for further analysis.
AB - From experimental studies it is well established that free-stream and wake-induced turbulence can increase the heat transfer on curved surfaces such as turbine blades or cylinders even if the mean flow matches corresponding laminar velocity profiles. Here, preliminary results of an investigation using (embedded) Direct Numerical Simulation (DNS) are reported that aim at identifying the responsible physical mechanisms for this phenomenon. The setup follows an existing experiment where a heated cylinder is subjected to the turbulent wake of a smaller cylinder placed upstream. The Reynolds number based on the diameter of the heated cylinder is Re = 48, 000. A key parameter identified in an experimental correlation is the characteristic turbulence level Tua that includes a dependency on Re and the mean flow acceleration. For the present study, Tua is an order of magnitude higher than those reported in any previous DNS. The obtained Nusselt number is in good agreement with the experimental correlation. More and better resolved data is currently produced for further analysis.
UR - http://www.scopus.com/inward/record.url?scp=84883079661&partnerID=8YFLogxK
U2 - 10.1007/978-3-642-15748-6_20
DO - 10.1007/978-3-642-15748-6_20
M3 - Conference contribution
AN - SCOPUS:84883079661
SN - 9783642157479
T3 - High Performance Computing in Science and Engineering 2010 - Transactions of the High Performance Computing Center, Stuttgart, HLRS 2010
SP - 263
EP - 271
BT - High Performance Computing in Science and Engineering 2010 - Transactions of the High Performance Computing Center, Stuttgart, HLRS 2010
PB - Springer
T2 - 13th Annual Results and Review Workshop on High Performance Computing in Science and Engineering, HLRS 2010
Y2 - 4 October 2010 through 5 October 2010
ER -