Fission products released from failed fuel rods in a PWR

[Pengtaofu]

TL;DR

fission product release from failed fuel rods in PWR

There are a lot of fission products accumulated in the fuel pellet and gap in the fuel cladding during PWR operation. Howeve, some iodine and noble gas will release to the primary loops in case of fuel failure. The fission product release rate can be described as the escape rate coefficient which means the possibility of one fission product atom released from defective fuel rods per second.
I am told that the relationshipn bewteen escape rate coefficient and linear heat rate, shown in the following figure, has been got in Canada experiment reactor at 1960s. Howerer I can not find any usefuel information about detail of the experiment. Could anyone help if one know the old experts.

 

[DEvens]

I can't help with the specific figure. But maybe you can find something on the CanTeach web site. Their publication library has a huge amount of information on line for free.

https://canteach.candu.org/Pages/Welcome.aspx

Oh, this place has done something to the link. The link is under the word "Welcome."

 

[Pengtaofu]

I can't help with the specific figure. But maybe you can find something on the CanTeach web site. Their publication library has a huge amount of information on line for free.

https://canteach.candu.org/Pages/Welcome.aspx

Oh, this place has done something to the link. The link is under the word "Welcome."

Thank you very much for sharing the web which include a lot of good public education for CANDU.

 

[Pengtaofu]

I can't help with the specific figure. But maybe you can find something on the CanTeach web site. Their publication library has a huge amount of information on line for free.

https://canteach.candu.org/Pages/Welcome.aspx

Oh, this place has done something to the link. The link is under the word "Welcome."

Thank you very much for sharing the web which include a lot of good public education for CANDU.

 

[Astronuc]

Summary: fission product release from failed fuel rods in PWR

I am told that the relationshipn bewteen escape rate coefficient and linear heat rate, shown in the following figure, has been got in Canada experiment reactor at 1960s. Howerer I can not find any usefuel information about detail of the experiment. Could anyone help if one know the old experts.

I did some work on release of fission products from failed fuel about 30 years. I had collected some of the earlier AECL reports on their experiments. At the time, I corresponded with Prof. Brent Lewis, who was involved with an experimental program with defected CANDU-type UO₂ fuel elements was carried out at CRNL from 1975 to 1983. I'll dig around to see if I still have some information. Lewis and colleagues wrote articles on their work, e.g., "Fuel Performance and Fission Product Release Studies for Defected Fuel Elements," Ref: https://www.tandfonline.com/doi/abs/10.13182/NT93-A34845

Meanwhile - https://www.nrc.gov/docs/ML0334/ML033450220.pdf

 

[Pengtaofu]

I did some work on release of fission products from failed fuel about 30 years. I had collected some of the earlier AECL reports on their experiments. At the time, I corresponded with Prof. Brent Lewis, who was involved with an experimental program with defected CANDU-type UO₂ fuel elements was carried out at CRNL from 1975 to 1983. I'll dig around to see if I still have some information. Lewis and colleagues wrote articles on their work, e.g., "Fuel Performance and Fission Product Release Studies for Defected Fuel Elements," Ref: https://www.tandfonline.com/doi/abs/10.13182/NT93-A34845

Meanwhile - https://www.nrc.gov/docs/ML0334/ML033450220.pdf

Thank you very much. I think your rich experience will be much helpful. Prof. Brent is a very famous expert and has publised a series of paper on the fission product release from failed fuel. I have discussed with Prof. Brent about fission product release from failed fuel rods but it is not very esay to find the origin of the coefficients. I think some elder colleagues may know the detailed information.
Actually the linear power in light water reactor uasally stay at about 180 W/cm, e.g. AP1000 and EPR. I am not sure the release rate coefficientor escape rate coefficient of fission product in the figure (400W/cm -500W/cm ) may be too conservative for AP1000 and APR1400.

 

[gmax137]

Actually the linear power in light water reactor uasally stay at about 180 W/cm, e.g. AP1000 and EPR. I am not sure the release rate coefficientor escape rate coefficient of fission product in the figure (400W/cm -500W/cm ) may be too conservative for AP1000 and APR1400.

The figure heat rates (10 to 20 kw/ft) look like hot channel rates; the 180 W/cm (5.5 kW/ft) value you mention is a core average rate. I would guess the fission product release rate would be a function of local (not core average) heat rate.

 

[Pengtaofu]

The figure heat rates (10 to 20 kw/ft) look like hot channel rates; the 180 W/cm (5.5 kW/ft) value you mention is a core average rate. I would guess the fission product release rate would be a function of local (not core average) heat rate.

Thank you very much for the remind and I agree with you. 5.5 kW/ft (180 W/cm) is indeed the average linear power. The average linear power can reach to 9.1 kW/ft (1.65 F∆Η) and 13.8 kW/ft (2.5 FQ) in the extreme conditions and may be the similar range.