COMSOL 6.4 - 3-Way Valve

Use a 3-way valve to either combine two inlet streams into one outlet or split one stream into two outlets, depending on flow control settings.


	The 3-Way Valve node can only be applied to points that are connected to exactly three edges. Two 3-Way Valve nodes cannot be placed on points that are endpoints of the same edge.

Point Selection

Select a junction point to place the 3-way valve.

Choose the edge where flow is always present as the . The other edges are assigned as and , which open or close depending on the valve setting.

Valve Specification

The arrow symbols in the graphics window mark . When the opening fraction xfr = 1, flow is fully directed from the to . Select the checkbox to change the branch.

Select a for the valve — (the default), , or .

Enter a value or expression for the xfr. The default is 1 ( is fully open).

Select : Choose how the valve opening affects flow response — Linear, Equal Percentage, or Quick Opening.

Loss Coefficient

Provide two values to define pressure loss behavior: pressure loss coefficient for the fully open valve

and coefficient at the closed position

,allowing small leakage, for and characteristics. Specify R1 (Rangeability) instead of

when the characteristic is selected.

Flow Coefficient

Provide two values that describe the valve capacity to pass fluid: coefficient at full opening

and lower bound

for and characteristics. Specify R1 (Rangeability) instead of

when the characteristic is selected.

Provide two values that describe the valve capacity to pass fluid: coefficient at full opening

and lower bound

for and characteristics. Specify R1 (Rangeability) instead of

when the characteristic is selected.

Select : Choose how the valve opening affects flow response — Linear, Equal Percentage, or Quick Opening.

Loss Coefficient

Provide two values to define pressure loss behavior: pressure loss coefficient for the fully open valve

and coefficient at the closed position

, allowing small leakage, for and characteristics. Specify R2 (Rangeability) instead of

when the characteristic is selected.

Flow Coefficient

Provide two values that describe the valve capacity to pass fluid: coefficient at full opening

and lower bound

for and characteristics. Specify R2 (Rangeability) instead of

when the characteristic is selected.

Provide two values that describe the valve capacity to pass fluid: coefficient at full opening

and lower bound

for and characteristics. Specify R2 (Rangeability) instead of

when the characteristic is selected.

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For details about pressure loss calculation, see 3-Way Valve in Theory for the Pipe Flow Interface.