OptiStruct is a proven, modern structural solver with comprehensive, accurate and scalable solutions for linear and nonlinear
analyses across statics and dynamics, vibrations, acoustics, fatigue, heat transfer, and multiphysics disciplines.

Elements are a fundamental part of any finite element analysis, since they completely represent (to an acceptable
approximation), the geometry and variation in displacement based on the deformation of the structure.

The different material types provided by OptiStruct are: isotropic, orthotropic, and anisotropic materials. The material property definition cards are used to
define the properties for each of the materials used in a structural model.

High Performance Computing leverages computing power, in standalone or cluster form, with highly efficient software,
message passing interfaces, memory handling capabilities to allow solutions to improve scalability and minimize run
times.

Contact is an integral aspect of the analysis and optimization techniques that is utilized to understand, model, predict,
and optimize the behavior of physical structures and processes.

OptiStruct and AcuSolve are fully-integrated to perform a Direct Coupled Fluid-Structure Interaction (DC-FSI) Analysis based on a
partitioned staggered approach.

OptiStruct and AcuSolve can be run on heterogeneous and remote platforms which are located on the same network domain. The communication
between OptiStruct and AcuSolve is via sockets.

The FSI results are output to the corresponding working directories. The structural (OptiStruct) results are output to the H3D file by default and can be post-processed in HyperView.

Aeroelastic Analysis is the study of the deflection of flexible aircraft structures under aerodynamic loads, wherein
the deformation of aircraft structures in turn affect the airflow.

OptiStruct provides industry-leading capabilities and solutions for Powertrain applications. This section aims to highlight OptiStruct features for various applications in the Powertrain industry. Each section consists of a short introduction, followed
by the typical Objectives in the field for the corresponding analysis type.

This section provides an overview of the capabilities of OptiStruct for the electronics industry. Example problems pertaining to the electronics industry are covered and common solution
sequences (analysis techniques) are demonstrated.

OptiStruct generates output depending on various default settings and options. Additionally,
the output variables are available in a variety of output
formats, ranging from ASCII (for example, PCH) to binary files (for example,
H3D).

A semi-automated design interpretation software, facilitating the recovery of a modified geometry resulting from a
structural optimization, for further use in the design process and FEA reanalysis.

The OptiStruct Example Guide is a collection of solved examples for various solution sequences and optimization types and provides
you with examples of the real-world applications and capabilities of OptiStruct.

OptiStruct and AcuSolve are fully-integrated to perform a Direct Coupled Fluid-Structure Interaction (DC-FSI) Analysis based on a
partitioned staggered approach.

OptiStruct and AcuSolve are
fully-integrated to perform a Direct Coupled Fluid-Structure Interaction (DC-FSI) Analysis
based on a partitioned staggered approach.

OptiStruct and AcuSolve
both include time-domain simulation capabilities that break the coupled solution
into a number of time steps. Since the governing equations of both OptiStruct and AcuSolve are
nonlinear, sub-iterations are typically required within each time step.

As the name suggests, Fluid-Structure Interaction simulates the interrelationship between fluid
flow and the solid body the fluid is in contact with. The behavior of the structure
affects the fluid and vice-versa in a coupled dynamic interaction that is captured
by dividing the time domain into time steps. For each time step, the exchanged
solution attributes are solved for from the governing equations until equilibrium
convergence is attained. Each such iteration run through towards convergence within
a time step is known as an exchange (in OptiStruct) or a
stagger (in AcuSolve). The fluid flow can be external to
the solid object, similar to an aircraft wing moving through air, or it can be
internal, like the flow of coolant in a condenser tube.

Target Applications

The Fluid-Structure Interaction capability aims at simulations of dynamic problems subjected to
fluid flow interactions and their complex interrelationship. It is recommended to
use this direct coupling method when the solid structural response variables
affecting the fluid domain vary significantly and result in large changes in the
fluid response. In this process, the responses from both domains are exchanged in
real time.

Note: For linear structural response the P-FSI (Practical FSI) solution
offered by AcuSolve may be more effective in solving
the linearized structural response with the nonlinear flow solution. For further
information on the P-FSI method, refer to the AcuSolve Command Reference Manual.

Supported Solutions

A large number of physical state variables affect the interrelationship between the structure and
the fluid domains. For example, pressure of the fluid at the interface can affect
displacement (and thereby the stress state) of the solid structure, and vice-versa.
The displacements at the structural interface can cause changes to fluid flow
leading to significant differences in fluid behavior across the entire domain.
Similarly, thermal loads on the structure can lead to temperature changes at the
structural interface, leading to a changing temperature field for the fluid.
Currently, in OptiStruct and AcuSolve the following solutions for the interaction is
supported:

Structural Fluid-Structure Interaction (Nonlinear Direct Transient
Structural Response of the structure).

Thermal Fluid-Structure Interaction (Linear Transient Heat Transfer Response
of the structure).

Combined structural and thermal heat transfer solutions in conjunction with fluid-structure interaction is currently not supported. You can either run Structural FSI or Thermal FSI, however, you cannot run both in the same run. In the following sections, SFSI refers to Structural Fluid-Structure Interaction and TFSI refers to Thermal Fluid-Structure Interaction for brevity and to avoid redundancy.

Fluid Structure Interaction - Workflow
Fluid-Structure Interaction involves working with two different software's, OptiStruct (the structural solver) and AcuSolve (the fluid solver).

Communication between OptiStruct and AcuSolve OptiStruct and AcuSolve can be run on heterogeneous and remote platforms which are located on the same network domain. The communication between OptiStruct and AcuSolve is via sockets.

Input
In this section the general input for any FSI run is discussed.

Run FSI
The OptiStruct and AcuSolve runs can be run either in serial or parallel mode.

Output
The FSI results are output to the corresponding working directories. The structural (OptiStruct) results are output to the H3D file by default and can be post-processed in HyperView.

Structural Fluid-Structure Interaction Analysis OptiStruct and AcuSolve are fully-integrated to perform a coupled Fluid-Structure Interaction Analysis based on a partitioned staggered approach.

Thermal Fluid-Structure Interaction Analysis OptiStruct and AcuSolve are fully-integrated to perform a coupled Fluid-Structure Interaction Analysis based on a partitioned staggered approach.