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Theory Manual
Physics and theory for nanoFluidX.
Physics
Learn more about the physics features in nanoFluidX.
Body Force
The body force, defined through acceleration in units of [m/s²], can be varied over time using an input file.

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nanoFluidX commands and parameters with examples.
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Theory Manual
Physics and theory for nanoFluidX.
- Physics
  Learn more about the physics features in nanoFluidX.
  - Body Force
    The body force, defined through acceleration in units of [m/s²], can be varied over time using an input file.
  - Contact Angle
    Enable the contact angle parameter to allow different wetting behaviors.
  - Energy Equation
    Energy equation in nanoFluidX is implemented so that it accommodates for conduction and convection heat transfer with initial or Dirichlet boundary conditions.
  - Surface Tension - Multiphase
    nanoFluidX implementation of the multiphase surface tension model heavily relies on the work of Adami et al.
  - Surface Tension - Single Phase and Adhesion
    Both single phase surface tension and adhesion modeling is based on the work of Akinci et al.
  - Viscosity Models
    nanoFluidX now supports both temperature-viscosity and non-Newtonian modeling behavior. For temperature-viscosity, three models were implemented: polynomial, Sutherland, and power law. For non-Newtonian, the Cross model is available, which can be used to approximate power law behavior without risking instabilities due to viscosity unboundness of the power model.
- Boundary Conditions
  Learn more about the boundary conditions in nanoFluidX.
- Measurements
  Learn more about the measurements features in nanoFluidX.
- Solver Features
  Learn more about advanced solver features in nanoFluidX.
Validation Manual
Error and Warning Messages
This glossary contains generic messages generated by nanoFluidX, their likely causes, and possible methods to resolve the related issues.
Frequently Asked Questions
This section provides quick responses to typical and frequently asked questions regarding nanoFluidX.
Bibliography
References used throughout the nanoFluidX manual.

Body Force

The body force, defined through acceleration in units of [m/s²], can be varied over time using an input file.

This file needs to be in the following form:

time

Bodyforce_x

Bodyforce_y

Bodyforce_z

As an example, use:

0	0	0	-9.81
1	0	0	-5.6
3	2.1	4.3	-7.2

There are no headers of any sort in the file.

The difference between input time values does not need be constant. The value of the gravity is interpolated linearly at each time step of the simulation between the closest greater and lesser time values of the input file.

To load the file, one line is necessary in the config file, inside the Domain parameters section:

bodyforcefile

inputFileName.txt

The data of this file are read one time at the beginning of the simulation. The start time in the prescribed motion file cannot be smaller than the initial time of the simulation.

No damping function is used.