- #1
Bubblyk
- 2
- 0
Hello Forumers and Physics-addicted Fellows!
I'm an applied nuclear engineering scientist by profession and thermal physicist by education. well nowadays I'm really involved into the describing the processes in Light Water Reactor core during Emergency Core Cooling System in action. In details I'm very interested in the thermal hydraulics of fuel rods and spacer grids during reflooding.
To simulate the quenching of fuel rods one needs to solve unsteady heat conductivity problem in solids and convection, radiation equation for two-phase flow. Moreover it's required to take into account physico-chemical interaction of zirconium alloy with water (heat effect, new oxide layer properties, variation of surface roughness), cladding ballooning, spacer grids effect.
In the other words the reflooding process is very complicated.
One of the main approaches to improve the reflooding process simulation is to predict film and transition boiling regimes of fuel rod more adequate. The criterion of heat regime change is assumed to be minimal film boiling temperature (Tmfb). Its very close to Leidenfrost temperature (TL)
Could we discuss the influence of any parameters on Tmfb? Perhaps you could have some valuable information, some theoretical ideas about the way of desribing this effect.
***Of course any questions about LWR reflooding/quenching are welcome and it would be very nice to discuss and share ideas and knowledge***
Best wishes,
Bubblyk
I'm an applied nuclear engineering scientist by profession and thermal physicist by education. well nowadays I'm really involved into the describing the processes in Light Water Reactor core during Emergency Core Cooling System in action. In details I'm very interested in the thermal hydraulics of fuel rods and spacer grids during reflooding.
To simulate the quenching of fuel rods one needs to solve unsteady heat conductivity problem in solids and convection, radiation equation for two-phase flow. Moreover it's required to take into account physico-chemical interaction of zirconium alloy with water (heat effect, new oxide layer properties, variation of surface roughness), cladding ballooning, spacer grids effect.
In the other words the reflooding process is very complicated.
One of the main approaches to improve the reflooding process simulation is to predict film and transition boiling regimes of fuel rod more adequate. The criterion of heat regime change is assumed to be minimal film boiling temperature (Tmfb). Its very close to Leidenfrost temperature (TL)
Could we discuss the influence of any parameters on Tmfb? Perhaps you could have some valuable information, some theoretical ideas about the way of desribing this effect.
***Of course any questions about LWR reflooding/quenching are welcome and it would be very nice to discuss and share ideas and knowledge***
Best wishes,
Bubblyk