Page 479 - ExtendSim User Guide
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Advanced Topics 453
LP technology
• If multiple Bias blocks have identical bias orders, the effective rates for these blocks cannot be predicted. The model will use one of the possible solutions.
• Merge and Diverge blocks with bias order are always lower on the bias list than any Bias block.
Table summarizing constraint and bias information
The following table summarizes the types of bias and constraint information (if any) Rate library blocks supply to the Executive for the calculation of effective rates:
Catch Flow Change Units Convey Flow Diverge
Interchange Merge
Throw Flow Valve
Neutral, Proportional, Select, Unbatch
Distributional, Priority, Supply Sensing
Batch, Neutral, Proportional, Select
Distributional, Demand Sensing, Priority
Critical Relational: Constraint Permanent
No Yes No No No Yes Yes No Depends Yes
Depends Yes
Yes No Depends Yes
Depends Yes
No No Yes No No No Yes No
Relational: Bias State Sensitive Order
No Yes No No No No Yes No No No
No Yes
Yes No No No
No Yes
No No Yes No No No No No
☞ Diverge and Merge blocks can imply a critical constraint depending on the branch parameter and the mode.
The relational constraint calculation
The table that follows describes how the relational constraint is calculated for blocks that pro- vide either permanent or state sensitive relational constraints.
For the purposes of this table:
• Xin is the effective inflow rate of a block and Xout is its effective outflow rate.
• Index i describes one of the inflow branches (for a Merge) and one of the outflow branches (for a Diverge).
• Thenumberofbranchesisn.
Block Calculation
Change Units The permanent boundary is Xin = factor*Xout
Discrete Rate

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