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Chiller Load Distribution Details

Let's say there are three chillers as follows.

  • Chiller no.1: 500RT
  • Chiller no.2: 1000RT
  • Chiller no.3: 1000RT
  • Chiller Sqeuence: Chiller no.1, Chiller mo.2, Chiller no.3
  • Optimum Part Load Ratio for all chillers: 0.75
  • Minimum Unloading Ratio for all chillers: 0.1

If I choose SequentialLpoad or Optimal for Load Distribution Scheme of PlantLoop, how is the load distributed to Chiller no.1 and Chiller no.2 the moment cooling demand exceeds 500 RT? The Minimum Unloading Ratio of chillers is set to 0.1. Is the evaporator cooling rate of Chiller no.1 reduced in consideration of the evaporator cooling rate of Chiller no.2? Or does the cooling rate of Chiller no.1 remain the same?

I looked at Engineering Reference, but I don't know how Minimum Unloading Ratio affects the chiller load distribution.

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Chiller Load Distribution Details

Let's say there are three chillers as follows.

  • Chiller no.1: 500RT
  • Chiller no.2: 1000RT
  • Chiller no.3: 1000RT
  • Chiller Sqeuence: Chiller no.1, Chiller mo.2, Chiller no.3
  • Minimum Part Load Ratio for all chillers: 0.1
  • Maximum Part Load Ratio for all chillers: 1.0
  • Optimum Part Load Ratio for all chillers: 0.75
  • Minimum Unloading Ratio for all chillers: 0.1

If I choose SequentialLpoad or Optimal for Load Distribution Scheme of PlantLoop, how is the load distributed to Chiller no.1 and Chiller no.2 the moment cooling demand exceeds 500 RT? The Minimum Unloading Ratio of chillers is set to 0.1. Is the evaporator cooling rate of Chiller no.1 reduced in consideration of the evaporator cooling rate of Chiller no.2? Or does the cooling rate of Chiller no.1 remain the same?same because the cooling rate of chiller no.2 is "false load" at the moment?

I looked at Engineering Reference says "Note: For all schemes, if the load for any individual component is less than the component load at the minimum PLR, the individual component model will false load or reduce duty cycle while operating at the minimum part load ratio until the load is met.", but I don't know how Minimum Unloading Ratio affects the the details of chiller load distribution.distribution when the second or third chiller is turned ON.

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