Batch Thawing: Oper. Conds Tab

BatchThawingOperConds.jpg
Variable Definitions, Ranges and Default Values

The following table shows a brief description of the variables appearing in this tab. The table also displays their default values and their generally acceptable range:

Variable

Default Value

Range

 

○ Final Temperature (oC)
The final temperature of vessel contents after the end of the operation.

25.0

Positive

○ Ignore Heating Utility
Check this box to ignore the heating utility type.

No

Yes/No

○ Power Type
Indicates the power type that is used by the operation if electricity is selected as the heat source. Click on the list box to bring up a list of available power types in order to select one.

<Std Power>

Any Power Type

● Power (kW)
The electrical power consumed for the operation.

0.0

Positive

○ Name (of Thawing Agent)
Indicates the thawing agent that is used by the operation if a thawing agent is selected as the heat source. Click on the list box to bring up a list of available thawing agents in order to select one.

<Hot Water>

Any Heating Agent

● Inlet Temp. (of Thawing Agent) (oC)
The inlet temperature of the thawing agent.

40.0

Positive

● Outlet Temp. (of Thawing Agent) (oC)
The outlet temperature of the thawing agent.

30.0

Positive

● Rate (of Thawing Agent) (kg/h)
The mass flow rate of the thawing agent.

0.0

Positive

● Duty (kcal/h)
The thawing duty of the operation (i.e., the heat transfer rate of the thawing agent).

0.0

Positive

○ Heat Transfer Efficiency(%)
The heating agent consumption efficiency. Specify a value below 100% to account for heat losses to the surroundings when a heating agent is used.

90.0

[0,100)

○ Setup Time (min)
The amount of time (per cycle) spent before each operation is carried in preparation for the actual execution of the operation. It may involve actions like cleaning, vacuuming, setting up of equipment, etc. which the user opted not to model explicitly.

5.0

Positive

◙ Thawing Time (min)
The actual duration of the operation.

15.0

Positive

○ Ignore Labor?
Check this box to ignore labor for this operation. This option is used only if the process time is set by a master-slave relationship.

Yes

Yes/No

◙ Thawing Rate (oC/min)
The thawing rate of the vessel contents.

1.0

Positive

◙ Overall UA (kcal/h-oC)
The product of overall heat transfer coefficient and heat transfer area.

10502.32

Positive

Symbol Key: ○ User-specified value (always input); ● Calculated value (always output); ◙ Sometimes input, sometimes output

Specification Choices / Comments

The following list describes the available specification choices in this tab; for more details on how these are implemented, see Batch Heating: Modeling Calculations.

•If the Heating Utility is ignored...

No energy balances are done.

•Duration options...

You can set the process time (heating time), or have the process time calculated based on heating rate, or match the duration of this operation to the duration of another operation by introducing a master-slave relationship between the two operations. There are two options for specifying the heating rate: you can either specify a constant heating rate or an exponential heating rate (specify the overall UA). If you introduce a master-slave relationship, the program will match the setup time, the process time and the turnaround time of this operation (the ‘slave’) with the corresponding times of the reference operation (the ‘master’ operation). For more details on how to setup a master-slave relationship, see The Scheduling Tab.