Slider-Crank
Crank-slider mechanism.
blockType: AcausalFoundation.Mechanical.Mechanisms.SliderCrank
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Description
Block Slider-Crank It is a crank-slider mechanism as a converter between the continuous rotational motion of the crank and the reciprocating motion of the slider.
The mechanism has two connections:
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Port C corresponds to a crank and represents a rotary mechanical port.
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The S port corresponds to the slider and represents a translational mechanical port.
Parameters Crank radius and Rod length describe the geometry of the mechanism. Inertia of the crank, set by the parameter Crank inertia, is necessary to pass the upper and lower dead points when the connecting rod is located exactly in the center of the crank.
Taking into account the rigidity of both the mechanism and the damping coefficient set by the parameters Slider stiffness and Slider damping, is necessary to reduce the inertial coupling between ports; too tight coupling can cause computational problems. The block provides rigidity and damping between the ideal position of the slider (calculated based on geometry) and the actual position of the mechanical translational port S. This correspondence avoids direct non-linear communication between ports. Higher rigidity leads to the fact that the movement approaches the ideal, but increases the computational rigidity of the system. Damping helps to smooth out the oscillations that can be caused by such rigidity of the system.
Variables
Use the parameter group Initial Targets to set the priority and initial target values for the block parameter variables before modeling. For more information, see Configuring physical blocks using target values.
Parameters
Parameters
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Crank radius —
crank radius
m | um | mm | cm | km | in | ft | yd | mi | nmi
Details
The radius of the crank. The parameter value must be greater than zero.
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Yes |
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Rod length —
connecting rod length
m | um | mm | cm | km | in | ft | yd | mi | nmi
Details
The length of the connecting rod connecting the crank and slider. The parameter value must be greater than Crank radius.
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Yes |
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Crank inertia —
moment of inertia of the crank
kg*m^2 | g*m^2 | kg*cm^2 | g*cm^2 | lbm*in^2 | lbm*ft^2 | slug*in^2 | slug*ft^2
Details
The moment of inertia of the crank, which is necessary to pass the upper and lower dead points when the connecting rod is located exactly in the center of the crank. The parameter value must be greater than zero.
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Yes |
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Slider stiffness —
rigidity of the slider position
N/m | mN/m | kN/m | MN/m | GN/m | kgf/m | lbf/ft | lbf/in
Details
Together with Slider damping provides a malleability that helps reduce the inertial coupling between ports. Higher rigidity causes the movement to approach the ideal, but increases the rigidity of the system. The parameter value must be greater than zero.
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Yes |
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Slider damping —
slider damping coefficient
N*s/m | kgf*s/m | lbf*s/ft | lbf*s/in
Details
Together with Slider stiffness ductility is provided, which helps to reduce the inertial connection between the holes. Higher damping values smooth out the oscillations that can be caused by stiffness. The parameter value must be greater than zero.
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Yes |