Abstract
Because “flow pattern” relates closely to design parameters of plant such as pressure drop and heat transfer coefficient, better knowledge of the flow pattern leads not only to deep understanding of the flow but also to accurate prediction of the parameters or to safe operation of plant. Therefore, “flow pattern” is an important and fundamental parameter as well as void fraction. Nevertheless the flow pattern has been judged mostly on a basis of visual observation. Therefore, it is desired to identify the flow pattern objectively and quantitatively.
Here, identification of flow pattern using differential pressure fluctuations is described. Behaviors of statistical parameters are discussed in the statistical parameter spaces. And also recent flow visualization methods using fast X-ray CT and HPIV are described.
