WOLFRAM SYSTEM MODELER
DoorOpeningModel simulating effect of opening and closing compartment doors on a refrigerator. |
![]() |
SystemModel["IndustryExamples.ConsumerProducts.Refrigerator.DoorOpening"]
This model simulates the effect of opening and closing the refrigerator and freezer compartment doors in a household refrigerator. The flow of heat and the circulation of air, both within the refrigerator and between the refrigerator and the external environment, are modeled with components from the HeatTransfer library and the FluidHeatFlow library.
View the model diagram for this model.
The other two models in this example are HotFood and NearEmpty, which compare the effects of adding hot food to a normally loaded and a near-empty refrigerator, respectively.
The model simulates the effect of opening and closing compartment doors according to a prespecified schedule. To see or modify the schedule, select the fridgeDoor or freezerDoor components in the DoorOpening model. The schedule is specified in the Parameters view at the bottom of Model Center.
To simulate the model, follow the steps below:
By default, the model is simulated over a period of 8000 seconds.
After simulating the model, a preferred stored plot will be displayed, showing the temperature of the air and food in the freezer compartment. An annotated version of the freezer compartment plot looks like this
You can see that there are several discontinuities in the rate of temperature change corresponding to predetermined events such as compartment doors opening and closing, and dynamic events such as thermostats being triggered.
You can visualize the various discrete events by clicking on the stored plot name Events
The resulting plot looks like this, depending on your choice of styles:
Try simulating the other two models in this example, HotFood and NearEmpty, to compare the effects of adding hot food to a normally loaded and near-empty refrigerator, respectively.
freezerSchedule |
Value: {690, 720, 1890, 1920, 3090, 3120, 15090, 15120, 16290, 16320, 17490, 17520, 36690, 36720, 37890, 37920, 39090, 39120, 47490, 47520, 48690, 48720, 49890, 49920} Type: Time[:] (s) Description: Schedule of freezer door open and close times |
---|---|
freezerAirFlow |
Value: 0.05 Type: VolumeFlowRate (m³/s) Description: Air flow rate while freezer door is open |
fridgeSchedule |
Value: {600, 620, 1200, 1220, 1800, 1820, 2400, 2420, 3000, 3020, 3600, 3620, 15000, 15020, 15600, 15620, 16200, 16220, 16800, 16820, 17400, 17420, 18000, 18020, 36600, 36620, 37200, 37220, 37800, 37820, 38400, 38420, 39000, 39020, 39600, 39620, 47400, 47420, 48000, 48020, 48600, 48620, 49200, 49220, 49800, 49820, 50400, 50420} Type: Time[:] (s) Description: Schedule of fridge door open and close times |
fridgeAirFlow |
Value: 0.1 Type: VolumeFlowRate (m³/s) Description: Air flow rate while fridge door is open |
![]() |
outerCase |
Type: OuterCase |
---|---|---|
![]() |
frozenFood |
Type: ConvectionCooledFood |
![]() |
freshFood |
Type: ConvectionCooledFood |
![]() |
heatPump |
Type: Cooling |
![]() |
ambient |
Type: FixedTemperature |
![]() |
freezerCompartment |
Type: HeatedPipe |
![]() |
fridgeCompartment |
Type: HeatedPipe |
![]() |
airCirculation |
Type: AirCirculation |
![]() |
freezerDoor |
Type: CompartmentDoor |
![]() |
fridgeDoor |
Type: CompartmentDoor |