The fluid-structure interaction and the fluid flow are studied in cases of a fuel tank sloshing and overturning. A
bi-phase liquid-gas material with an ALE formulation is used to define the interaction between water and air in the
fuel tank.
The purpose of this example is to study the energy propagation and the momentum transfer through several bodies, initially
in contact with each other, subjected to multiple impact. The process of collision and the energetic behavior upon
impact are described using a 3-dimensional mode.
The impact and rebound between balls on a small billiard table is studied. This example deals with the problem of
defining interfaces and transmitting momentum between the balls.
After a quasi-static pre-loading using gravity, a dummy cyclist rides along a plane, then jumps down onto a lower
plane. Sensors are used to simulate the scenario in terms of time.
The purpose of this study is to demonstrate the use of quadratic interface contact using two gears in contact with
identical pitch diameter and straight teeth. Two different contact interfaces are compared.
The problem of a dummy positioning on the seat before a crash analysis is the quasi-static loading which can be resolved
by either Radioss explicit or Radioss implicit solvers.
The crashing of a box beam against a rigid wall is a typical and famous example of simulation in dynamic transient
problems. The purpose for this example is to study the mesh influence on simulation results when several kinds of
shell elements are used.
A square plane subjected to in-plane and out-of-plane static loading is a simple element test. It allows you to highlight
element formulation for elastic and elasto-plastic cases. The under-integrated quadrilateral shells are compared with
the fully-integrated BATOZ shells. The triangles are also studied.
The modeling of a camshaft, which takes the engine's rotary motion and translates it into linear motion for operating
the intake and exhaust valves, is studied.
The ditching of an object into a pool of water is studied using ALE and SPH approaches. The simulation results are
compared to the experimental data and to the analytical results.
A rubber ring resting on a flat rigid surface is pushed down by a circular roller to produce self-contact on the inside
surface of the ring. Then the roller is simultaneously rolled and translated so that crushed ring rolls along the
flat surface.
Separate the whole model into main domain and sub-domain and solve each one with its own timestep. The new Multi-Domain
Single Input Format makes the sub-domain part definition with the /SUBDOMAIN keyword.
The aim of this example is to introduce /INIVOL for initial volume fractions of different materials in multi-material ALE elements, /SURF/PLANE for infinite plane, and fluid structure interaction (FSI) with a Lagrange container.
A heat source moved on one plate. Heat exchanged between a heatsource and a plate through contact, also between a
plate and theatmosphere (water) through convective flux.
Impacts of rotating structures usually happen while the structure is rotating at a steady state. When the structure is
rotating at very high speeds, it is necessary to include the centrifugal force field acting on the structure to correctly
account for the initial stresses in the structure due to rotation.
A heat source moved on one plate. Heat exchanged between a heatsource and a plate through contact, also between a
plate and theatmosphere (water) through convective flux.
A heat source moved on one plate. Heat exchanged between a heatsource and a plate
through contact, also between a plate and theatmosphere (water) through convective
flux.
Thermal analysis, like heat exchange (between two contact surfaces, between heat
object and surrounding atmosphere though convection or radiation, inside the object
through conduction), deformation is due to thermal expansion or heat generated, due
to friction can be simulated in Radioss. In this example
heat exchange is discussed between a moving heat source and one plate, due to
contact and also between plate and atmosphere (water) through convective flux.
A heat source with a constant temperature of 800K is moved under imposed displacement on one
plate with an initial temperature of 298K. The dimension of the heat source is 5mm x
5mm and the plate is 100mm x 100mm.
Units: mm, ms, g, N, and MPa
/MAT/LAW2 and /HEAT/MAT are used to describe the aluminum
heat source and plate, with the following characteristics:
Material Properties
Initial density
2.8 x 10-3
Young's modulus
70000
Poisson ratio
0.33
Yield stress
206
Hardening parameter
450
Hardening exponent
0.5
Room temperature
298
Specific heat
2.51
Initial temperature for heat source
800 [K] and for plate: 398 [K]
Thermal conductivity coefficient AS
0.23
Model Method
/HEAT/MAT is an additional material law card used to describe the
material thermal character. So the material ID in the material law in
/MAT and in /HEAT/MAT must be the same.
The thermal parameter defined in /HEAT/MAT will recover the same
parameters which are defined in the material law.
Heat capacity provides heat and mass the ability to change the temperature. In
engineering and science, it is recommended to use specific heat capacity, which is
heat capacity divided by mass, in SI unit. Heat capacity is for aluminum. Refer to Table 1 in the Theory Manual Appendices for more information on heat
capacity of ordinary material.
For the thermal conductivity coefficient , . Thermal conductivity for aluminum, and constant thermal conductivity. Set . Since thermal conductivity , then , in this case.
With /IMPTEMP, imposed temperature will be set on a group of
nodes. The source constant temperature is defined for heat source.
Use /CONVEC to describe the heat exchange between a structural
component and its surrounding atmosphere (infinite room).
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
/CONVEC/convec_ID/unit_ID
convec_flux_title
surf_IDT
fct_IDT
sens_ID
Ascalex
Fscaley
Tstart
Tstop
H
The surrounding atmosphere is water with a constant temperature of 298K, which is
described in function, fct_IDT
(Figure 4).
Where, H is the heat transfer coefficient between structural
component and its surrounding infinite room with unit . In general, the convective heat transfer
coefficient for water (free convection) is about 20 - 100 and water (forced convection) is about 50 - 10000 . Forced convection in water is .
In /INTER/TYPE7, heat exchange between the heat source and plate
during the contact is defined Kthe=1 to activate
heat transfer between main and secondary.
If Ithe =
1
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
Kthe
fct_IDK
Tint
Ithe_form
AscaleK
Frad
Drad
Fheats
Fheatm
Set Ithe_form to 1 for heat
exchange between all pieces in contact.
There are two ways to define heat exchange between contact parts.
Define constant heat exchange coefficient using Kthe ( in SI unit). In this case, fct_IDK =
0.
If fct_IDK
0, the heat exchange coefficient is the function of contact pressure
using this curve and Kthe is the
scale factor.
(1)
Interfacial heat transfer coefficient, described conductive heat flux through a unit area
of a plate with a particular thickness. The range of this heat transfer coefficient
can be very large, which will affect the accuracy of simulation. To get a more
accurate result, an experimental test is required.(2)
To not consider heat friction, set
Fheats and
Fheatm to 0.
Results
Figure 5 shows nodal temperature at time
10[ms], 20[ms] and 30[ms]. Part of heat transferred to plate through contact.
Therefore, the temperature under the trace increased. The temperature on the plate
decreased during the time, due to the convection with water.
The nodal temperature on Nodal N641, N1034, N958 and N1708 are illustrated in Figure 6.
Nodal N641 is not under trace. The temperature changed, only due to
convection with water.
Nodal N1034, N958 and N1708 are under trace. At first the temperature
decreased before the heat source began, due to convection with water, and
then increased, due to the heat exchange from the heat source through
contact. Once the heat source is removed, the temperature decreased again,
due to the heat conduction inside the material and convection with water. So
the slope of the temperature decrease is much larger than N641 (only
convection).