Cross-Flow NTU Effectiveness Calculator
Both-unmixed crossflow empirical ε=1−exp[N^.22/C(exp(−CN^.78)−1)], finite C=0 and NTU=0 limits; not existing parallel-flow law. Caller independently establishes units, regime, calibration and applicability; this does not establish design-code compliance, authenticity, operational safety, treatment efficacy or a validated forecast.
Description
Crossflow effectiveness depends on transfer units, heat-capacity ratio and flow arrangement.
Crossflow effectiveness depends on transfer units, heat-capacity ratio and flow arrangement.1
A both-streams-unmixed correlation must match the independently established exchanger geometry. Use Cross-Flow NTU Effectiveness Calculator to evaluate the supplied inputs under the specific model below.
When to use Cross-Flow NTU Effectiveness Calculator
Use Cross-Flow NTU Effectiveness Calculator to evaluate the supplied inputs under the specific model below. Establish the units, measurement scope and applicable model or recipe assumptions before entering values.
How to use Cross-Flow NTU Effectiveness Calculator and understand its results
- Establish the units, measurement scope and applicable model or recipe assumptions before entering values.
- Enter Ntu, Capacity ratio, Caller both streams unmixed verified using the field table and validation rules below, then run the tool.
- Read Crossflow unmixed effectiveness and interpret units, signs, ordering and placeholders as explained below.
- If the tool reports an input error, correct that field and rerun. A successful false result, empty match list or unknown-evidence placeholder has the specific meaning described here; check the limitations before applying the result.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| ntu | Ntu | number | Required; constraints below |
| capacityRatio | Capacity ratio | number | Required; constraints below |
| callerBothStreamsUnmixedVerified | Caller both streams unmixed verified | boolean | Required; constraints below |
Enter nonnegative NTU, a capacity ratio from 0 to 1, and true only when the both-streams-unmixed crossflow assumption is independently verified. False is rejected. Zero NTU returns zero effectiveness; zero capacity ratio uses 1−exp(−NTU). Otherwise use the stated empirical correlation. Neither the flow geometry nor applicability is established by this calculation.
ε = 1−exp(((exp(−Cr×NTU^0.78)−1)×NTU^0.22)/Cr), with zero branches above Field order, units and branch conditions follow the implementation explanation above.
| Output field | Meaning | Value type |
|---|---|---|
| crossflowUnmixedEffectiveness | Crossflow unmixed effectiveness | number |
{
"input": {
"ntu": 1,
"capacityRatio": 0.5,
"callerBothStreamsUnmixedVerified": true
},
"output": {
"crossflowUnmixedEffectiveness": 0.5447637120146873
}
}Limitations and assumptions
A both-streams-unmixed correlation must match the independently established exchanger geometry. Apply the exact scope and assumptions described above.
All listed fields require explicit values. Unexpected fields, incorrect types, nonfinite numbers and sparse arrays fail validation. Domain-specific bounds, alignments and supported tokens are stated above; extremely large inputs or outputs can also be rejected. These errors differ from successful results such as false, no matches or unknown evidence.
Alternative or Complementary methods
Use Aeration Oxygen Requirement Calculator for a related task: Aeration demand combines oxygen requirements with a declared credit and transfer efficiency.
Use Box Model Dispersion Calculator for a related task: A well-mixed box model balances a source with ventilation and background concentration.
References
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Cross-Flow NTU Effectiveness Calculator — tool.io
Similar or alternative tools
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