New Fuel Connectors

Created Freitag 02 März 2018

Models affected by Update


The following models are affected by the Update of the fuel connectors:

Manual Conversion

With ClaRa 1.3.0 the handling of fuel property calculation has been improved. The properties are calculated in a fuel model and do always depent on the local composition of the fuel. To obtain the same results as before, the fuel definition in a fuel boundary has to be adapted.
For models built with ClaRa 1.2.2 or lower, the update is fully backwards compatible as the old models from the ClaRa_Obsolete are used. However, the power plant models can be converted manually. This can be done by right-clicking on the model and chosing the option "change class". It is illustrated in the picture below.

Manual Update Tasks

In case you have used these models, just change the modifiers of fuel models in:

There are three cases to be considered:

Case 1 In Fuel Boundaries the Parameter LHV_calculationType is set to "Verbandsformel"

switch the fuel according to the following table:
old fuel | new fuel
Coal_v1 | Fuel_verbandsformel_v1
Coal_v2 | Fuel_verbandsformel_v2
Coal_reference | Fuel_verbandsformel_v3

Case 2 In Fuel Boundaries the Parameter LHV_calculationType is set to "predefined"

If no changes to LHV_predefined and cp are made in the fuel boundaries switch according to the following table
old fuel | new fuel
Coal_v1 | Fuel_refvalues_v1
Coal_v2 | Fuel_refvalues_v2
Coal_reference | Fuel_refvalues_v3
xi_const or xi (active connector if variable_xi = true) must be recalculated as follows:


Case 2 In Fuel Boundaries the Parameter LHV_calculationType is set to "predefined" and changes are made to LHV_predefined and/or cp

In that case a new fuel must be defined recalculating the cp and LHV such that the respective values are met with the given composition. This could be done using the following functions:
- Use the function ClaRa_Obsolete.Basics.Functions.ConvertFuel_LHV to adapt the new LHV_waf (water and ash free).
- Use the function ClaRa_Obsolete.Basics.Functions.ConvertFuel_cp to adapt the new cp.
- Use the function ClaRa_Obsolete.Basics.Functions.ConvertFuel_xi to adapt the new composition (combustible, ash, water).
- Use the function ClaRa_Obsolete.Basics.Functions.ConvertFuel_xi_waf to adapt the new water and ash free composition (C,H,O,N,S).

Adapt the modifier of the fuel inside the SimCenter according to the following example:
-> redeclare ClaRa.Basics.Media.FuelTypes.Fuel_refvalues_v3 fuelModel1(C_cp={"cp_new",1000,4190}, xi_e_waf={"xi_waf"}, C_LHV={"LHV_new",0,-2500e3})
And copy the obtained value for xi_new to the xi_const value of your fuel boundaries.

Limits of conversion

In version 1.0.0 illogical combinations of LHV calculation types and variable compositions at the fuel boundaries were featured that are now handled correctly:

These bug fixes may lead to result changes when applying variable compositions

Remark: This procedure will produce the same results as before, unless a fuel with "LHV calculation type==predefiend " changes composition with time.


Backlinks: ClaRa:A User Guide:Revisions:v1.3.0