# Pressure drop in fuel assemblies

Hello!
I am studying the mentioned topic I am confused in calculating the average value of friction factor in sub channels ... please help ??

Nidum
Gold Member
thank you!

can you provide me the link from where i can get the MIT exam paper to solve .. for these topics

third link is not working ...

Nidum
Gold Member
Nidum
Gold Member

again not working
time out error is displayed on screen

Nidum
Gold Member
You must have a local problem since all links are working ok for me in UK .

What country are you in ?

I am from Pakistan

oh ok !
and its ok thank you for your kind support
best regards!

Hi, you wrote about pressure drop in fuel assemblies. But you have to specify, whether you mean pressurized water reactors (single phase flow) or boiling water reactors (two-phase flow).

In general, total fuel assembly pressure drop is formed by fuel bundle frictional drop (dependent on relative roughness of fuel rods, reynolds number, hydraulic diameter etc.) and other pressure drops of structural elements (top and bottom nozzle, spacing grids or mixing grids).

In general, it is not so simple to calculate pressure drops in fuel assemblies (especially the spacing grids) and it belongs to key know-how of certain fuel manufacturer. Mostly, pressure drops are measured in experimental hydraulic loops, rather than calculated.

If you want to know more, specify your problem. Here are some valuable sources:

Frictional losses - single phase
Pressure drop - two-phase

sehrish shakir
Hi, you wrote about pressure drop in fuel assemblies. But you have to specify, whether you mean pressurized water reactors (single phase flow) or boiling water reactors (two-phase flow).

In general, total fuel assembly pressure drop is formed by fuel bundle frictional drop (dependent on relative roughness of fuel rods, reynolds number, hydraulic diameter etc.) and other pressure drops of structural elements (top and bottom nozzle, spacing grids or mixing grids).

In general, it is not so simple to calculate pressure drops in fuel assemblies (especially the spacing grids) and it belongs to key know-how of certain fuel manufacturer. Mostly, pressure drops are measured in experimental hydraulic loops, rather than calculated.

If you want to know more, specify your problem. Here are some valuable sources:

Frictional losses - single phase
Pressure drop - two-phase
Thank you very much for such a kind response,
i have studied these topics ... these are quite interesting ...
i am studying single phase "pressurized water reactor" ... my main focus is on the pressure drop across fuel rods and pressure drop in steam generator , i am neglecting all minor losses ... i have calculated the pressure drop with and without spacers ...and also considering the lateral flow pattern..
now i am not getting the main purpose of the coefficient calculations ... significance of "p/D" ratio ??? in general how we calculate p/D ratio for triangular lattice in a cylindrical shell of steam generator ? what values of pressure drop are acceptable ... thank you in advance :)