In this test the following three types of fluid behaviors are tested:

A fluid cavity is primarily defined to consider the coupling between the deformation of the structure and the pressure exerted by the fluid on the structure. These tests verify the capability of ABAQUS/Explicit to model this interdependence accurately by defining a fluid cavity based on the surfaces of the structure. The structure enclosing the fluid cavity is modeled using different feasible combinations of finite elements. The volume of the cavity is changed intentionally during the analysis by prescribing displacement boundary conditions on a particular set of nodes, which results in a change in the cavity pressure.

In this test fluid flow between a cavity and its environment or between two fluid cavities is modeled using the *FLUID EXCHANGE, *FLUID EXCHANGE PROPERTY, and *FLUID EXCHANGE INTERACTION options. Test cases include flow of a single gas, flow of a mixture of gases, and flow of hydraulic fluids. For pneumatic fluids, both isothermal and adiabatic behaviors are tested.

This test verifies the fluid inflator properties that can be defined in ABAQUS/Explicit using the *FLUID INFLATOR, *FLUID INFLATOR PROPERTY, and *FLUID INFLATOR INTERACTION options to simulate the flow characteristics of the actual inflators. The inflator mass flow rate and inflator temperature are assumed to be linearly varying with time for the TEMPERATURE AND MASS type of fluid inflator property. For the TANK TEST type of inflator property, the tank volume and tank pressure are set to be the same as the cavity volume and cavity pressure obtained in the TEMPERATURE AND MASS case. For the DUAL PRESSURE type of fluid inflator property definition, the tank volume and tank pressure data are taken from the TANK TEST case and the inflator pressures at different inflation times are determined from the equations given in “Defining inflators,” Section 7.13.4 of the ABAQUS Analysis User's Manual. The data necessary to define the PRESSURE AND MASS type of inflator property are obtained from the previous three cases. In the test a total of ten fluid cavities are modeled using the surface-based fluid cavity capability. Fluid cavities 1–8 and 10 are inflated with the same ideal gas or a mixture of ideal gases that are initially present in the cavity. However, the molar mass fractions of the gases inflating the fluid cavity filled with a mixture are considered to be different from the initial molar mass fractions. In the case of cavity 9, the constituents of the gas mixture inflating the cavity are considered to be different from the constituents present in the cavity initially.