Tank

A container for fluid or bulk matter with infinite capacity, input at the top and output at the bottom. Optionally can contain some initial fluid (infinite amount of initial fluid is also possible). When the tank is not full, its content is always located at the bottom, and is filled from top. A non-full tank can accept input flow at any rate. When the tank is full, its input rate is restricted by the output rate (but not vice versa). When the tank is empty, its output rate is limited to the input rate.

The specified rate cannot be lower than the value of Utils.RATE_TOLERANCE constant, i.e. 1.0e-9. If rate value falls below this value after recalculation, it will be snapped to 0.

The Fluid Library will try to maximize the out flow of all fluid sources; therefore, the priority of Tank out flow is set to 1 by default. Sometimes, to resolve flow priority conflicts, you may need to customize the out flow priority by further increasing it.

Tank can also serve as a source of fluid or as a disposal container with infinite capacity.

Although in the real tank different fluids can get mixed, the Tank block preserves the order of the incoming batches and transfers them to the output in the FIFO order. The output batch can be chosen to be the same as the original input batch, set to the default batch, or to a custom batch. You can also customize the batch initially contained in the tank, if any.

The Tank block allows you to define actions executed in the event of tank becoming full, empty, or the amount falling below or raising above the specified level. In addition, you can react to a new batch appearing the input or at the output.

Capacity

The maximum amount the tank can contain. This value cannot be less than the value of Utils.TOLERANCE. Infinite capacity can be set by typing infinity in the property’s field.

Syntax: double capacity

Initial amount

The amount initially contained in the tank. This value cannot be less than the value of Utils.TOLERANCE. Infinite initial amount can be set by typing infinity in the property’s field.

Syntax: double initialAmount

Limited output rate

If the option is selected (the value is equal to true), you are able to specify a custom upper limit of the rate the tank outflow rate.

Syntax: boolean limitRateOut

Maximum output rate

[Visible and applies only if the Limited output rate option is set]
Custom upper limit of the tank outflow rate. The default value is 10 cubic meters per second.

Syntax: double maxRateOut
Set new value at runtime: set_maxRateOut(new value)

Custom priority

If the option is set (the value equals true), the priority of the tank outflow will be set to Output flow priority, otherwise it equals 1. Priority affects the LP solver when it tries to maximize the flow through the system.

Syntax: boolean customPriority
Set new value at runtime: set_customPriority(true) or set_customPriority(false)

Output flow priority

[Visible and applies only if the Custom priority option is set]
Custom priority of the tank outflow in the overall flowchart. Must be a positive integer.

Syntax: int priorityOutCustom
Set new value at runtime: set_priorityOutCustom(new value)

Custom initial batch

If set, the fluid initially contained in the tank will be of type Initial batch. If not, it will be BatchTypes.DEFAULT_BATCH.

Syntax: boolean customInitialBatch
Set new value on startup: set_customInitialBatch(new value)

Initial batch

[Visible and applies only if the Custom initial batch option is set]
Defines the batch initially contained in the tank.

Syntax: Object initialBatch
Set new value on startup: set_initialBatch(new value)

Output batch is

Defines the output batch of the tank. One of the following:

Same as the original batch — same is the original batch that has flown into the tank
Default — set to the default batch BatchTypes.DEFAULT_BATCH
Custom — defined by the Output batch parameter below

Get the value: modeOutputBatch
Set new value at runtime: set_modeOutputBatch(new value)
Valid values:
Tank.OUTPUT_BATCH_IN1
Tank.OUTPUT_BATCH_DEFAULT
Tank.OUTPUT_BATCH_CUSTOM

Output batch

[Visible and applies only if the Output batch is option is set to Custom]
Defines the batch to be created at the tank output.

Value type: Object
Local variable: Object originalbatch — the initial batch

Storage tank

Here you can specify the name of Storage tank space markup shape used to animate this tank (both in 2D and 3D animation).

Syntax: StorageTank storageTank

Show batches in flowchart

If set, the block icon will display the current batch color.

Syntax: boolean showBatchesInFlowchart

On full

Action executed when the tank gets full. If the tank is full initially, is not executed at the start of simulation.

On empty

Action executed when the tank becomes empty. If the tank is initially empty, the action is not executed at the start of simulation.

Action on above

If the option is set (the value equals true), you can specify the action executed when the amount of fluid in the tank goes up and reaches a particular threshold.

Syntax: boolean actionOnAbove

On above

[Visible and applies only if the Action on above option is set]
Action executed when the amount of fluid in the tank increases and reaches the threshold specified in the Amount parameter right above. Is not executed when the amount is initially above or at the threshold, or if the threshold is crossed while the amount is decreasing.

Local variable: double amount — the current amount

Action on below

If the option is set (the value equals true), you can specify the action executed when the amount of fluid in the tank decreases and reaches a particular threshold.

Syntax: boolean actionOnBelow

On below

[Visible and applies only if the Action on below option is set]
Action executed when the amount of fluid in the tank decreases and reaches the threshold specified in the Amount parameter right above. Is not executed when the amount is initially below or at the threshold, or if the threshold is crossed while the amount is increasing.

Local variable: double amount — the current amount

On new batch at input

Action executed when a new batch appears at the tank input. It will not necessarily start flowing into the block.

Local variable: Object batch — the batch

On new batch at output

Action executed when a new batch reaches the tank output, even if the output batch is set to default or custom.

Local variable: Object batch — the batch

On rate change

Action executed when any of the flow rates (input or output) changes.

Changing something in the action may result in another immediate rate change and immediately following another call of On rate change, so the user can possibly create a livelock.

Local variables:
double inrate — the current input rate
double outrate — the current output rate

Fluid amount

Function	Description
double amount()	Returns the amount currently contained in the tank (total of all batches). If the value is less than the value of Utils.TOLERANCE, returns 0.
double amount(AmountUnits units)	Returns the amount of fluid (in given units) currently contained in the tank (total of all batches). If the value is less than the value of Utils.TOLERANCE, returns 0.
double amountPassedIn()	Returns the total amount passed through the input port of the tank since the start of the simulation.
double amountPassedIn(AmountUnits units)	Returns the total amount of fluid (in given units) passed through the input port of the tank since the start of the simulation.
double amountPassedOut()	Returns the total amount passed through the output port of the tank since the start of the simulation.
double amountPassedOut(AmountUnits units)	Returns the total amount of fluid (in given units) passed through the output port of the tank since the start of the simulation.
double amountMin()	Returns the historical minimum of the fluid amount in the tank.
double amountMin(AmountUnits units)	Returns the historical minimum of the fluid amount in the tank in given units.
double amountMax()	Returns the historical maximum of the fluid amount in the tank.
double amountMax(AmountUnits units)	Returns the historical maximum of the fluid amount in the tank in given units.
double amountAverage()	Returns the average fluid amount in the tank over the total operating time.
double amountAverage(AmountUnits units)	Returns the average fluid amount in the tank over the total operating time in given units.
boolean isFull()	Tests if the tank is full, i.e. the amount equals the tank capacity. Returns true if the tank is full, and false otherwise.
boolean isEmpty()	Tests if the tank is empty. Returns true if the tank is empty, and false otherwise. There can still be a zero-size batch in an empty tank in case it has appeared at the input, but has not actually started flowing in.

Utilization

Function	Description
double utilization()	Returns the currently utilized fraction of the tank capacity, i.e. amount() / capacity. If the tank’s initial amount and capacity are both set as infinite, the function will return 1.
double utilizationTotal()	Returns the tank average utilization throughout the total operating time, i.e. the integral instant utilization / (capacity * operating time)

Flow rate

Function	Description
double currentRateIn()	Returns the current flow rate of fluid that goes in.
double currentRateIn(FlowRateUnits units)	Returns the current flow rate (in given units) of fluid at the tank input.
double currentRateOut()	Returns the current flow rate of fluid that goes out.
double currentRateOut(FlowRateUnits units)	Returns the current flow rate (in the given rate units) of fluid that goes out.

Batches

Function	Description
int numberOfBatches()	Returns the number of batches currently present in the tank, including possible zero-length batches.
Object getBatch(int index)	Returns the batch with the specified index. Batch with index 0 is the closest to the tank output, batch with the index numberOfBatches() - 1 is the last batch closest to the tank input.
double getBatchSize(int index)	Returns the size of the batch with the specified index. Batch with index 0 is the closest to the tank output, batch with the index numberOfBatches() - 1 is the last batch closest to the tank input.
double getBatchSize(int index, AmountUnits units)	Returns the size of the batch (in given units) with the specified index. Batch with index 0 is the closest to the tank output, batch with the index numberOfBatches() - 1 is the last batch closest to the tank input.
double updateOutputBatch()	Forces immediate recalculation of the output batch and its color according to the current parameters settings.
double getBatchOffset(int index)	Returns the sum of sizes of all batches under (closer to output) than the batch with a given index. Intended use is custom animation.

Resetting statistics

Function	Description
void resetStats()	Resets statistics collected for this block, including the statistics collected for its ports.

in

The input port.

out

The output port.

How can we improve this article?

Send