LOCAL HEAT TRANSFER OF TUBES IN THE CRITICAL FLOW REGIME FOR Pr > 1
Experimental data on the local heat transfer of single tubes and banks of tubes in the range of Reynolds number from l×l05 to 2×l06 in cross flows of water at Pr > 1 are presented. For single tubes the location of the point of loss of hydrodynamical stability and of the point of boundary layer separation has been determined. At critical values of Re > 106 minimum of heat transfer is removed upstream as an indication of the start of laminar - turbulent transition. Local heat transfer in banks suggest a qualitatively different pattern in the critical flow regime as compared to the subcritical regime.