An experimental study of transient boiling was initiated for the purpose of clarifying the criteria for bubble nucleation and initial growth in a non-uniform thermal environment.
High speed, close-up motion pictures (at 16,000 frames per second) of the emerging vapor cap and its subsequent dynamic behavior illustrate the dramatic effects imposed by the temperature distribution in the adjacent superheated liquid.
Once the vapor bubble has successfully "capped" the nucleation cavity, it may then either collapse, remain stationary for a period of time prior to a slow but increasing rate of growth, or immediately begin its growth period. Depending upon the rate of growth relative to the state of development of the relaxation and evaporation microlayers, the bubbles may also exhibit subsequent instabilities characterized by dramatic changes in their rate of growth.