2 replies to this topic

[DANA-IF]

Hi friends ;

Could anyone explain us please the difference between rating , design and debottleneck when we run a model in flarenet and the purpose of each one ?

[M_Menessy]

Hello,

 

As I know, rating mode is used when you have existing flare system and you would like to check if the system is performing well according to the criteria of Mach number, low temperature, allowable backpressure and/or Rho.v2. In case of problems, results will be shown in red below the source or pipe that has a problem (warnings are shown in that way for all modes). 

 

Design mode is used to design new flare system (again based on certain criteria). I mean by design term is to select the pipe nominal diameters to match Mach number of 0.7 in tailpipes and 0.5 for sub-headers and header for example. Also, don't forget that backpressure is one of the most important constraints to design according to. This mode may increase or decrease the pipe nominal diameters.

 

Debottleneck mode is used to check the areas in flare system that need to have larger pipe diameters. So, you will have larger pipes in case of not matching the criteria but pipe diameters will not decrease. 

 

To conclude, Design mode is used for unexisting flare system that is still in the design phase. Rating and debottleneck modes are used to check if the existing flare system is performing well when some modifications take place. For example, connecting other relieving devices to the same flare header or assuming adjacent areas to suffer from fire at the same time and these areas are not separated by some physical boundaries. This may result in higher relief load and higher backpressure in the system which may lead to decreased relief loads of some PSVs and as a result, increased hazards are introduced to the system. Thus, you have to check (rating) and suggest (debottleneck) the pipes, sub-headers and headers that may need to change.

 

I hope you find this answer sufficient for your question.  

 

M Menessy

Edited by M_Menessy, 24 September 2014 - 01:24 AM.

[flarenuf]

nadia

 

the best thing to do is to run through the worked examples in teh getting started manual , they will give you a basic understanding of eth program and its use.

 

I really do wonder on the fact you are looking to use Flarenet for engineering use when you seem not to understand the basic concepts of its use.

 

flarenuf