The Basics of Two-Phase Flow

Assignment :

Start the Second Homework

My goal for this lecture is to lay down basic terminology for two-phase flow, and give a feeling for what various void fractions represent. Processes in power systems  involve various forms of two-phase flow, and it is specially important when dealing with accident scenarios in nuclear power plants. If you are going to work in this field you need to understand the basic terminology (jargon).

Two Stages of Science

1. Description and Classification (Organization)

2. Predictive Theories

There are three historical phases in the development of theoretical science. The first beginning at the dawn of history, and only fading in recent years is "back-of-the-envelop science". All predictions were made with hand calculations. The next phase, "science by computer," began in the 1950's with the advent of useful programmable computers. The third and terminal phase of science became noticeable a couple decades ago. It is "science by view graph," and has probably been driven by the dominance of government funding of scientific research.

Three Tasks of Numerical Simulation


Simple Two-Phase Flow Regimes

Flow Regime Map

Physical Feel for void fractions (see my sample void calculations)

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