PropPRVstatic
Library
HydraulicsByFluidon/Components/Valves/PressureValves
Description
The component PropPRVstatic is a model of a proportional pressure relief valve without dynamic characteristics. For all pressures exceeding opening pressure the valve opens and the flow increases linearly following the slope given by parameters Nominal volume flow and Nominal pressure difference.
The opening pressure is calculated by Input * Input scaling. If input should be in the range of 0 to 10 [V] and maximum opening pressure 200e5 Pa, Input scaling must be set to 20e5 [Pa/V] (200e5 / 10). If the opening pressure should be given directly by input, Input scaling must be set to 1. Please note: the upper value of opening pressure is not limited but only proportional to input.
If the valve is balanced (Balanced valve = true) the valve opens when the supply pressure exceeds the opening pressure:
Opening condition: fluidPortA.p > opening pressure + pAmbient
If the valve is not balanced (Balanced valve = false) the tank pressure is considered:
Opening condition: fluidPortA.p > opening pressure + fluidPortB.p
If Find exact opening point is set to true, the valve opens exactly at the time when the opening pressure is exceeded. If it is set to false, the valve may open earlier or later depending on simulation's step size. This setting avoids an event (and probably a slow down of simulation) by using noEvent().
The component part PRVstatic is not a model of a pressure relief valve according to its physical structure. It merely represents the characteristic behavior of a pressure relief valve. Therefore dynamic effects such as forces due to inertia will not be represented.
Parameters
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_InputScaling | InputScaling | Input scaling | Scalar | |
mo_NominalVolumeFlow | NominalVolumeFlow | Nominal volume flow | Scalar | |
mo_NominalPressureDifference | NominalPressureDifference | Nominal pressure difference | Scalar | |
mo_ReferenceDensity | ReferenceDensity | Reference density for volume flow and pressure difference | Scalar | |
mo_deadVolume | deadVolume | Dead volume at ports | Scalar | |
mo_Balanced | Balanced | Balanced valve | Scalar | true |
mo_exact | exact | Find exact opening point | Scalar | true |
mo_pA | pA | pA | Structure | |
mo_pA/fixed | fixed | Cell of scalars | true | |
mo_pA/start | start | Cell of scalars | ||
mo_pB | pB | pB | Structure | |
mo_pB/fixed | fixed | Cell of scalars | true | |
mo_pB/start | start | Cell of scalars |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo_forwardFluidProperties | forwardFluidProperties | Forward fluid properties between ports | Scalar | true |
| Name | Label | Description | Data Type | Valid Values |
|---|---|---|---|---|
mo__nmodifiers | Number of Modifiers | Specifies the number of modifiers | Number | |
mo__modifiers | Modifiers | Add new modifier | Structure | |
mo__modifiers/varname | Variable name | Cell of strings | 'volumeFlowA' | |
mo__modifiers/attribute | Attribute | Cell of strings | 'start' | |
mo__modifiers/value | Value |
Ports
| Name | Type | Description | IO Type | Number |
|---|---|---|---|---|
fluidPortA | implicit | Hydraulic port A | input | 1 |
fluidPortB | implicit | Hydraulic port B | input | 2 |
Input | implicit | Set value of opening pressure | input | 3 |