Heat transfer frequency response of a cylinder in pulsating cross flow

• Applicant: Professor Wolfgang Polifke, Ph.D.
• Subject Area: Fluid Mechanics ; Technical Thermodynamics
• Term: from 2014 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 253709273

The heat transfer of a cylinder in cross flow is of fundamental as well as applied interest in thermo-fluidmechanics. The dynamics of heat transfer under pulsating flow conditions - first investigated by Lighthill in 1954 - poses some very intriguing questions. The applicant and co-workers have determined in preliminary studies the frequency response of heat transfer by a combination of computational fluid dynamics and system identification. It was found that the dynamics are governed by the interaction of various response mechanisms with different time lags, which by superposition account for several non-trivial features of the heat transfer frequency response. The objective of the proposed research is to carry out an in-depth, comprehensive analysis of the dynamic response of shear stress and heat transfer of a cylinder in cross flow. First, identification quality is to be improved through advanced identification schemes and alternative model structures. Then the following open questions shall be addressed: dynamics at low Reynolds numbers, phase of the frequency response at high Strouhal numbers, limitations of Lighthill's analysis.

• DFG Programme: Research Grants