Ball Valve (IL)

A ball valve in an isothermal liquid network.

ball valve il

Description

The Ball Valve (IL) unit is a ball valve in an isothermal liquid network. The ball valve consists of a ball with an orifice that can rotate inside the valve body. When the valve is open, the orifice is completely blocked with the valve body port. When the valve is closed, the ball rotates and reduces the amount of overlap, thereby reducing the effective area of the port. Ball valves are often used for flow shut-off applications because they can reliably shut off flow over many cycles. Ball valves are less common in applications where precise throttling is required.

The block can be parameterised analytically or with tabular data. If the Ball valve parameterization is set to `Area of overlapping circles', the block defines the overlapping area between the valve orifice and the ball orifice as the opening area such that

where

and are the radii of the valve port and ball port, respectively;
- displacement of the centre of the ball bore relative to the centre of the valve port;
- rotation of the ball valve set through the S port. The valve is fully closed at rad and fully open at rad.

Mass flow equation

The unit calculates the flow rate through the valve using the pressure-area relationship for the orifices, which is as follows

where

- flow coefficient;
- is the average density of the fluid;
- valve opening area, where , and is the Leakage area parameter.
- critical pressure drop, determined from the critical Reynolds number value .

The unit calculates the critical pressure drop as follows:

If the Flow coefficient parameterization is set to Cd coefficient and area, the value for can be set using the Discharge coefficient parameter. If the Flow coefficient parameterization is set to Cv coefficient USCS, the block calculates the value of as

where is the value of the Maximum Cv flow coefficient parameter.

If Flow coefficient parameterization is set to Kv coefficient SI, the block calculates the value of as

where is the value of the Maximum Kv flow coefficient parameterization. In these equations, is 1 psi and is 1 bar.

Ports

Conserving

# A — isothermal liquid port

Details

isothermal liquid port, corresponds to valve port A.

Program usage name

port_a

# B — isothermal liquid port

Details

isothermal liquid port, corresponds to valve port B.

Program usage name

port_b

Input

# S — valve position, rad

Details

Valve position value, in rad. The value 0 indicates a fully closed valve and the value π/2 indicates a fully open valve.

Data types	`Float64`.
Complex numbers support	No

Parameters

# Ball valve parameterization — ball valve parameterization
Area of overlapping circles | Tabulated data

Details

Option for selecting the parameterization method of the block:

Area of overlapping circles - areas of overlapping circles.
Tabulated data - use of tabulated data.

Values	`Area of overlapping circles` \| `Tabulated data`
Default value	`Area of overlapping circles`
Program usage name	`valve_parameterization`
Evaluatable	No

# Flow coefficient parameterization — flow coefficient parameterization
Kv coefficient (SI) | Cv coefficient (USCS) | Cd coefficient and area

Details

Option to select the method of flow coefficient parameterization:

Kv coefficient (SI) - parameterization via capacity factor - water flow rate in m^3/h through a fully open valve at a temperature of 15°C and a pressure drop of 1 bar.
Cv coefficient (USCS) - parameterization via capacity factor - water flow rate in gallons per minute through a fully open valve at 60°F with a pressure drop of 1 psi.
Cd coefficient and area - parameterization via dimensionless flow coefficient , which determines the efficiency of the valve.

Values	`Kv coefficient (SI)` \| `Cv coefficient (USCS)` \| `Cd coefficient and area`
Default value	`Kv coefficient (SI)`
Program usage name	`flow_coefficient_parameterization`
Evaluatable	No

# Maximum valve flow factor (Kv) — maximum valve capacity factor
m^3/s | m^3/h | cm^3/s | mm^3/s | ft^3/s | lpm | l/s | gpm | gal/s | gal/h

Details

The maximum value of the valve capacity factor. This value must correspond to the fully open position.

Dependencies

To use this parameter, set the Ball valve parameterization to Area of overlapping circles' and the Flow coefficient parameterization to `Kv coefficient (SI).

Units	`m^3/s` \| `m^3/h` \| `cm^3/s` \| `mm^3/s` \| `ft^3/s` \| `lpm` \| `l/s` \| `gpm` \| `gal/s` \| `gal/h`
Default value	`49.0 m^3/h`
Program usage name	`K_v_max`
Evaluatable	Yes

# Maximum valve flow coefficient (Cv) — maximum valve capacity factor
m^3/s | m^3/h | cm^3/s | mm^3/s | ft^3/s | lpm | l/s | gpm | gal/s | gal/h

Details

The maximum value of the valve capacity factor. This value must correspond to the fully open position.

Dependencies

To use this parameter, set the Ball valve parameterization to Area of overlapping circles' and the Flow coefficient parameterization to `Cv coefficient (USCS).

Units	`m^3/s` \| `m^3/h` \| `cm^3/s` \| `mm^3/s` \| `ft^3/s` \| `lpm` \| `l/s` \| `gpm` \| `gal/s` \| `gal/h`
Default value	`32.0 gpm`
Program usage name	`C_v_max`
Evaluatable	Yes

# Discharge coefficient (Cd) — flow coefficient

Details

The correction factor is the ratio of the actual mass flow rate to the theoretical mass flow rate through the valve.

Dependencies

To use this parameter, set the Flow coefficient parameterization to `Cd coefficient and area'.

Default value	`0.64`
Program usage name	`C_d`
Evaluatable	Yes

# Cross-sectional area at ports A and B — area at the inlet or outlet of the valve
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

The cross-sectional area at the inlet and outlet ports A and B. This area is used when calculating the mass flow rate through the valve.

Dependencies

To use this parameter, set the Ball valve parameterization to `Area of overlapping circles'.

Units	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`(pi*25^2)/4 mm^2`
Program usage name	`port_area`
Evaluatable	Yes

# Ball bore area — ball bore area
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

Cross-sectional area of the valve ball bore.

Dependencies

To use this parameter, set the Ball valve parameterization to `Area of overlapping circles'.

Units	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`(pi*20^2)/4 mm^2`
Program usage name	`ball_bore_area`
Evaluatable	Yes

# Leakage area — clearance area in fully closed position
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

The sum of all clearances when the valve is in the fully closed position. Any area less than this value equates to the specified leakage area. This parameter contributes to the stability of the numerical solution by maintaining flow continuity.

Dependencies

To use this parameter, set the Ball valve parameterization to `Area of overlapping circles'.

Units	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`1e-10 m^2`
Program usage name	`leakage_area`
Evaluatable	Yes

# Valve flow factor (Kv) vector — valve capacity factor for a given ball rotation
m^3/hr

Details

Valve capacity factor for a given ball rotation. Each element of the vector is related to the elements of the vector from the Ball rotation vector parameter. The first element corresponds to valve leakage and must be non-zero.

Dependencies

To use this parameter, set the Ball valve parameterization parameter to `Tabulated data' and the Flow coefficient parameterization parameter to `Kv coefficient (SI)'.

Units	`m^3/hr`
Default value	`[1e-6, .34, .76, 1.6, 2.45, 4.1, 5.75, 9.4, 13, 28, 50] m^3/hr`
Program usage name	`K_v_vector`
Evaluatable	Yes

# Valve flow coefficient (Cv) vector — valve capacity factor for a given ball rotation
m^3/s | m^3/h | cm^3/s | mm^3/s | ft^3/s | lpm | l/s | gpm | gal/s | gal/h

Details

Dependencies

To use this parameter, set the Ball valve parameterization parameter to `Tabulated data' and the Flow coefficient parameterization parameter to `Cv coefficient (USCS)'.

Units	`m^3/s` \| `m^3/h` \| `cm^3/s` \| `mm^3/s` \| `ft^3/s` \| `lpm` \| `l/s` \| `gpm` \| `gal/s` \| `gal/h`
Default value	`[1e-6, 0.58, 1.15, 1.90, 2.80, 4.3, 7.0, 10.5, 17.0, 26.0, 32.0] gpm`
Program usage name	`C_v_vector`
Evaluatable	Yes

# Area vector — area for a given ball rotation
m^2 | cm^2 | ft^2 | in^2 | km^2 | mi^2 | mm^2 | um^2 | yd^2

Details

The flow area for a given ball rotation. Each element of the vector is related to the vector elements from the Ball rotation vector parameter. The first element corresponds to valve leakage and must be non-zero.

Dependencies

To use this parameter, set the Ball valve parameterization to `Tabulated data' and the Flow coefficient parameterization to `Cd coefficient and area'.

Units	`m^2` \| `cm^2` \| `ft^2` \| `in^2` \| `km^2` \| `mi^2` \| `mm^2` \| `um^2` \| `yd^2`
Default value	`[1e-10, 62.5, 125, 187.5, 250, 312.5, 375, 437.5, 500, 562.5, 625] mm^2`
Program usage name	`area_vector`
Evaluatable	Yes

# Ball rotation vector — ball rotation
deg | rad | rev | mrad

Details

The ball rotation for a given flow capacity or area. The elements of this vector must relate to the elements of the Valve flow coefficient (Cv) vector, the Valve flow factor (Kv) vector, or the Area vector.

Dependencies

To use this parameter, set the Ball valve parameterization parameter to `Tabulated data'.

Units	`deg` \| `rad` \| `rev` \| `mrad`
Default value	`[0 ,0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0].*(pi/2) rad`
Program usage name	`phi_vector`
Evaluatable	Yes

# Critical Reynolds number — upper limit of Reynolds number for laminar flow

Details

Upper Reynolds number limit for laminar flow through the valve.

Default value	`150.0`
Program usage name	`Re_critical`
Evaluatable	Yes