Development of double-wall-tube steam generator (No.9); Report of the initial thermal hydraulic tests and the DNB preliminary test

not registered; Yatabe, Toshio; not registered; not registered

The small test rig of double wall tube steam generator (DWTSG) was installed and experiments were started to evaluate the feasibility of DWTSG. Main objectives of this test rig are to obtain data on structural integrity of the double wall tube under steam generator circumstances such as DNB and instability flow and capability of leak detection. In order to study the basic thermal characteristics of the double wall tube steam generator, the tests for the thermal hydraulic characteristics and a preliminary DNB test were carried out from November, 1991. It is important to evaluate the data widely and timely, so preliminary results, analysis methods and results are described in this report. FOllowing results have been obtained so far. (1)The small test rig has a sufficient heat transfer capability. (2)Many kinds of thermal hydraulic data to evaluate the feasibility of DWTSG are obtained. (3)Test results shows the necessity of re-examination for the heat transfer calculation method at low load. (4)The structural integrity of the double wall tube caused by DNB must be maintained. We are going to carry out the experiments and evaluation.