#Limitation of quiri series#

Experimental studies were previously reported concerning failure of a front hydraulic fitting on a C reactor `Operational-charge-discharged` geometry. Such information is of value in updating of reactor hazards evaluation reports.

The objective of the subject experiments was to determine what rear header pressures would be required to achieve adequate cooling of a K reactor fuel assembly during such a post-scram period. The only means of heat removal from the affected tube and fuel elements during the post-scram period would be by reverse flow of hot water from the rear header. However, the reactor power reduction would not be immediate nor absolute and more » would be dictated by the time required to insert the emergency control rods and by post-scram delayed fission and fission product decay heating. The failure of the inlet coolant piping between the front header and the process tube on a reactor would cut off the flow of cooling water to the fuel elements but should immediately initiate a reactor scram by causing a low trip on the Panellit pressure monitor. These experiments were conducted to investigate fuel element temperatures which could result from coolant flow loss following a failure of the inlet piping to a process tube at a K reactor. Reported herein are the results of laboratory heat transfer experiments. Some discrepancies have been found in the data and as yet are unexplained therefore, the results are presented with no claim to their accuracy. However, the results of these experiments are of considerable current interest and, for that reason, certain high spots of the data are presented here at this time. This means that checking and presenting the data in final form is a monumental job which requires considerable time. During the test runs, data from these transient experiments are recorded on high speed recording instruments, each of which has a calibration which is subject to change regardless of the efforts expended by the experimenters.

#Limitation of quiri series#

After preliminary runs were made and reported, a further series of runs were planned and run which would include K as well as BDF type data and would define more closely the upper limit of the panellit protection.

Transient heat transfer experimentation on a large scale is not common and many difficulties have been encountered. As a result, a program was initiated by the thermal Hydraulics Operation of HLO to perform a series of transient heat transfer experiments which would define the process tube response to (1) rapid plugging in the process tube assembly, (2) slow plugging in the process tube assembly, and (3) power more » excursions above normal of varying amounts. However, the actual conditions in a process tube following a plugging occurrence sufficient to cause unstable flow are transient rather than steady state, and cannot be determined with great precision except by transient state experimentation. Current Panellit protection procedures, termed instability limits, come from calculations based on steady state experiments.