## Material density multiplier in cell card

New ideas for code development

### Material density multiplier in cell card

Jaakko,
Sometimes there is a need in a more convenient way to vary density in cells with the same material - one of the most common examples is a BWR fuel pin. Since materials may take quite a lot of memory resources (and input lines), it would be nice to change material density in a cell by using a coefficient, like in MCNP. However, in contrast to MCNP, this coefficient should be optional. A multiplier constant would be the best solution from my point of view. Such multiplier
1. would allow the user to change density in the whole array of cells by adjusting the original density in material card, and
2. would illustrate how big the difference between the original (in mat card) and the actual (in cell card) density is.

I believe the mutliplication can be easily implemented in the tracking routines, right?
KTH Reactor Physics (Stockholm, Sweden) neutron.kth.se
Andrei Fokau

Posts: 77
Joined: Thu Mar 25, 2010 12:25 am
Location: KTH, Stockholm, Sweden

### Re: Material density multiplier in cell card

Sound's good. However, the delta-tracking method basically allows also a continuous change in material density, which is something I've wanted to do for a long time. So it might be a good idea to combine these features into something more general. How about a "density variation card", which would take material name as input parameter, together with cell and factor or function parameters, such as polynomial / trigonometric coefficients?
- Jaakko

Jaakko Leppänen

Posts: 2013
Joined: Thu Mar 18, 2010 10:43 pm
Location: Espoo, Finland

### Re: Material density multiplier in cell card

Jaakko Leppänen wrote:Sound's good. However, the delta-tracking method basically allows also a continuous change in material density, which is something I've wanted to do for a long time. So it might be a good idea to combine these features into something more general. How about a "density variation card", which would take material name as input parameter, together with cell and factor or function parameters, such as polynomial / trigonometric coefficients?

Jaakko, you rock! Just tell us when we will enjoy this :)
KTH Reactor Physics (Stockholm, Sweden) neutron.kth.se
Andrei Fokau

Posts: 77
Joined: Thu Mar 25, 2010 12:25 am
Location: KTH, Stockholm, Sweden