This is a sensible-load ε-NTU model. Dehumidifying coils require surface temperature, dew point, and latent-load treatment.
How to read it
The ε-NTU curve shows capacity saturation as UA increases.
The air path reads inlet-to-outlet temperature drop.
The load map finds combinations where airflow and UA are insufficient.
Learn Chilled Water Coil Performance by dialogue
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When reading Chilled Water Coil Performance, where should I look first? Moving Airflow changes both the plots and the result cards.
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Start with Effectiveness, but do not treat the number as the whole answer. Use ε-NTU curve to confirm the assumed state, then read Air temperature path for the distribution or trend. The ε-NTU curve shows capacity saturation as UA increases.
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I can see why Airflow changes Effectiveness. How should I judge the influence of Water flow?
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Move Water flow in small steps and watch Cooling capacity. That reveals which term is controlling the result. This is a sensible-load ε-NTU model. Dehumidifying coils require surface temperature, dew point, and latent-load treatment. A single operating point is not enough; sweep the realistic scatter range.
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What is Airflow-UA load map for? It feels like the ordinary curve already tells the story.
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Airflow-UA load map is for finding boundaries where the condition becomes risky or margin collapses quickly. The air path reads inlet-to-outlet temperature drop. In First-pass chilled-water coil selection, the important question is often what happens after a small change, not only the nominal value.
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So if Effectiveness is within the target, can I accept the condition?
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Treat this as a first-pass review. It helps with Checking outlet-temperature degradation after airflow increase and Separating UA limits from water-flow limits on existing coils, but final decisions still need standards, measured data, detailed analysis, and vendor limits. The load map finds combinations where airflow and UA are insufficient.
Practical use
First-pass chilled-water coil selection.
Checking outlet-temperature degradation after airflow increase.
Separating UA limits from water-flow limits on existing coils.
FAQ
Start with Effectiveness and Cooling capacity. Then use ε-NTU curve to confirm the assumed state and Air temperature path to read distribution or bias. The ε-NTU curve shows capacity saturation as UA increases
Move Airflow alone, then move Water flow by a comparable amount and compare the change in Effectiveness. Airflow-UA load map shows combinations where margin or performance changes quickly.
Use it for First-pass chilled-water coil selection. Instead of trusting a single point, widen the input range and check whether Effectiveness keeps enough margin before moving to detailed analysis.
This is a sensible-load ε-NTU model. Dehumidifying coils require surface temperature, dew point, and latent-load treatment. Final decisions still require standards, measured data, detailed analysis, and vendor limits.