Feed Limited Chemostat Washout
Screen the feed-limited Monod chemostat washout boundary from flow, volume, and feed substrate; equality is the zero-biomass boundary.
Description
A chemostat's dilution rate competes with growth support from its feed substrate.
A chemostat's dilution rate competes with growth support from its feed substrate. Washout can occur below μmax when the feed concentration limits achievable Monod growth.1
Screen the feed-limited Monod chemostat washout boundary from flow, volume, and feed substrate; equality is the zero-biomass boundary.
When to use Feed Limited Chemostat Washout
Use this tool to screen the feed-limited Monod chemostat washout boundary from flow, volume, and feed substrate; equality is the zero-biomass boundary.
Prepare the sample, count, growth or assay measurements requested by this tool. Confirm units, sampling periods and reporting bases; supply independently established comparison criteria where requested.
How to use Feed Limited Chemostat Washout and understand its results
- Prepare the sample, count, growth or assay measurements requested by this tool. Confirm units, sampling periods and reporting bases; supply independently established comparison criteria where requested.
- Enter feedLitersPerHour, cultureVolumeLiters, maximumGrowthRatePerHour, feedSubstrateGramsPerLiter, halfSaturationGramsPerLiter using the field table and calculation rules, then run the tool.
- Read dilutionRatePerHour, feedLimitedGrowthRatePerHour, washoutAtOrAboveBoundary. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| feedLitersPerHour | Feed liters per hour | number; minimum: 0 | Required |
| cultureVolumeLiters | Culture volume liters | number | Required |
| maximumGrowthRatePerHour | Maximum growth rate per hour | number | Required |
| feedSubstrateGramsPerLiter | Feed substrate grams per liter | number; minimum: 0 | Required |
| halfSaturationGramsPerLiter | Half saturation grams per liter | number | Required |
Enter nonnegative flow and feed substrate, positive culture volume, μmax per hour and Ks in g/L. The tool returns D and feed-limited rate per hour and flags D at or above that rate. Equality is the zero-biomass boundary. Zero feed makes the threshold zero.
D=feedFlow/volume; μFeed=μmax Sfeed/(Ks+Sfeed) Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| dilutionRatePerHour | Dilution rate per hour | number |
| feedLimitedGrowthRatePerHour | Feed limited growth rate per hour | number |
| washoutAtOrAboveBoundary | Washout at or above boundary | boolean |
{
"input": {
"feedLitersPerHour": 2,
"cultureVolumeLiters": 10,
"maximumGrowthRatePerHour": 0.5,
"feedSubstrateGramsPerLiter": 1,
"halfSaturationGramsPerLiter": 1
},
"output": {
"dilutionRatePerHour": 0.2,
"feedLimitedGrowthRatePerHour": 0.25,
"washoutAtOrAboveBoundary": false
}
}Limitations and assumptions
The screen assumes the supplied Monod steady-state model and no cell retention. Maintenance, death, inhibition and changing conditions are not included; it does not simulate washout timing.
Numeric inputs must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors. A successfully returned false flag is an evaluated outcome; its meaning is explained above.
Alternative or Complementary methods
Use Two Point Monod Parameters: Solve the exact two-point Monod model for mu-max and Ks, rejecting observations that imply nonpositive saturation parameters. For a complementary task, use Chemostat Residual Substrate: Solve the non-washout Monod chemostat branch and check whether the feed can sustain its residual substrate concentration.
References
-
Feed Limited Chemostat Washout — tool.io
Similar or alternative tools
- Two Point Monod Parameters
Solve the exact two-point Monod model for mu-max and Ks, rejecting observations that imply nonpositive saturation parameters.
- Chemostat Residual Substrate
Solve the non-washout Monod chemostat branch and check whether the feed can sustain its residual substrate concentration.