Translating chord length distribution into bubble size distribution using numerical and analytical backward transforms

The bubble sizes and their distribution affect directly to other hydrodynamic behavior of two-phase systems such as flow regime, gas-liquid interfacial area, and mass heat transfer between the phases. However, it is difficult to obtained bubble sizes and their distribution directly. By using the probe technique, the vertical length that bubbles insert the probe, or chord length, can be obtained instead of bubble sizes. In order to get the bubble sizes as well as their distribution, some techniques have to be used. This paper discuss the approaches, which are numerical and analytical backward transform, to estimate bubble size distribution from a set of chord length data obtained by a double sensor conductivity probe which installed in the air water vertical loop facility installed in KAERI. The image technique is also used to measure bubble sizes, which used to compare with ones obtained by the probe