| Popis: |
Several aspects of the wave instability model of film boiling are studied on a horizontal flat surface in a shallow pool. These include the inter-bubble spacing, the bubble size, and the bubble frequency, as well as the geometric pattern of the bubbles. Both still and high speed photography indicate that the bubbles form on an alternating square grid pattern. The inter-bubble spacing is shown to equal the two-dimensional ‘most dangerous’ wavelength λ d . The vapor bubble diameter is larger than previously reported at the minimum film boiling point (MFB). The heat transfer calculated from the photographically measured parameters is within 25% of the average heat transfer determined by conduction and condensation. |
