7/29/2019 NEM Heliostat
2/2
NEM Energy b.v.
A solar energy system benefits from ANSYSstructural simulation,
leading to a sustainable,innovative power source.
Use ANSYS Parametric Design Language(APDL) command snippets to
evaluate themodel at different angles and wind speeds aspart of a
batch process.
Benefits
Shell elements save computational time andcan export rotation
angles important tostudy the deformation of the heliostat.
Automatic contact creation reduces theamount of time compared to
manuallycreating contacts.
Plastic deformation calculations ensure thatthe permanent
deformation is small enoughto not affect the accuracy of linear
analysis forstructural predictions.
The output from the APDL command snippetsis exported to a ray
tracing routine that deter-mines the effect of structural
deformation onthe light reaching the receiver. These resultsare, in
turn, used to calculate the potentialamount of electricity that can
be generated byeach heliostat design.
Simulation helps NEM to improve performanceand reduce the cost
of heliostat designs at amuch faster pace than could be
accomplishedsolely by building and testing prototypes.
Company Description
NEM Energy b.v. is a leading company in the fieldof
steam-generating equipment for power generation and industrial
applications throughout theworld. The firms driving forces are
distinctiveknow-how and continuous technological innova-tion,
leading to new applications such as steamgeneration from solar
power.
ANSYS, Inc.
[email protected] 2012 ANSYS, Inc.
All Rights Reserved.
Structural results show deformation of heliostat
Heliostat model
A concentrated solar power (CSP) system is asustainable source
of power. It uses mirrors orlenses to concentrate sunlight onto a
small areato drive a heat engine connected to an electrical
power generator. These systems are now expe-riencing rapid
growth. The power tower systemtype of CSP uses a field of
sun-tracking mirrorscalled heliostats to concentrate light onto
areceiver atop a tower. The heat is used to directlyproduce steam,
or it can be stored to producesteam after the sun goes down. The
steam pow-ers a conventional turbine generator to
produceelectricity.
Challenges
A key design challenge for NEM is to increase thestiffness of
the mirrors for CSP. This ensures thatas muchreflectedlight as
possible is directedto the target, called a receiver, without
payinga cost premium. Stiffness is critical becausejust a 1 degree
rotation error for a heliostat 380meters away from the tower
results in a 6.6 metertracking error (the reflected light is
delivered 6.6meters from the intended target on the tower).
Technology Used
ANSYS Mechanical
Engineering Solution
Model the 16 mirror segments, or facets, ofthe heliostat with
shell (mesh) elements.
Use ANSYS Workbench to automaticallyadd more than 1,000 contacts
using a 5 mmtolerance value.
Employ plastic deformation calculations onsmall sections of the
model to account forpermanent deformations of the structure.
