Experiments on stability, flow structure, and dynamics in a lid-driven cavity.

01.01.2004 - 31.07.2005
Research funding project
The stability of the two-dimensional, steady, incompressible flow in a rectangular cavity is investigated experimentally. The cavity is formed by two facing cylinders tightly sealing the cavity. The cylinders have large radii in comparison to the height and the width of the cavity. Hence, curvature effects of the cylinders are considered negligible. The top wall as well as the limiting walls in axial direction are made from acrylic glass to allow insight for observations and diagnosis. To minimize end-wall effects the span ratio of the cavity has been extended to Lambda approxiately 11, much larger than most previous experiments which used Lambda = 1 to Lambda = 3. First investigations have been made for cross-sectional aspect ratios of Gamma = 0.725 and Gamma = 1.0 and for Reynolds numbers up to 1200. The flow instabilities were examined by visualization with help of fine aluminium flakes and two-component LDA measurements using polystyrene bead seeding. The results obtained show a good qualitative agreement with published numerical data. In particular, the critical Reynolds numbers for the onset of steady and oscillatory three-dimensional flow, predicted recently, were be confirmed. The experimental data, however, show a weak asymmetry and deviate slightly from the numerical data. This discrepancy can be attributed to side-wall effects.

People

Project leader

Institute

Grant funds

  • Deutsche Forschungsgemeinschaft e.V (EU) German Research Foundation (DFG)

Keywords

GermanEnglish
strukturstructure
dynamikdynamic
cavitycavity

Publications