Geometry optimization of ejector
If you are interested in doing CFD simulations in a
world-leading company in an industry market that
operates under extreme conditions where you can
have an affect on how units are produced in the
future, this thesis will be something for you!
Background
Our products are built on a history of industry
leadership dating back to the early 1960s when we
developed the first commercial Hot Isostatic Press
(HIP). Today, Avure’s technological innovations
have
expanded HIP-processing
parameters
to
encompass greater pressures, higher temperatures
and growing capacities. We develop products from
research and small-volume HIP-presses to the
world’s largest HIP production systems.
Hot Isostatic Presses employ pressurized heated gas for consolidation, densification, or bonding
of high performance components and materials. Processed parts can achieve 100% of maximum
theoretical density, with exceptional resistance to fatigue, impact, wear and abrasion. The
products from the presses can be used in for example plain bodies, aviation engines, car engines,
human-body implants and in the offshore–industry to mention a few. To obtain these high
material properties the HIP operates under extreme conditions with pressures reaching 2000 bar
at temperatures of 2200°C. The combination of these extreme conditions with sizes up to 2
meters in diameter and 5 meters in height the amount of stored energy is enormous. At these
temperatures and pressures the ideal gas law does no longer apply. The furnace is the heart of the
HIP system and Avure provides state of the art furnace designs with a wide range of styles, hot
zone materials and advanced temperature measurement techniques. Standard HIP cycles range
from 10 to 24 hours, with most of this time devoted to natural, unassisted cooling. To shorten
cycle times, Avure has introduced its exclusive Uniform Rapid Cooling (URC) furnace that uses
either an ejector or a variable speed fan to circulate cooler gas uniformly throughout the work
zone. With this cooling system the HIP cycle can be cut with up to 70%. To meet future market
demands, technological advances in HIP are creating a new generation of applications, which
needs further development of the furnaces where numerical Computational Fluid Dynamics
(CFD) will be an essential part.
Task description
The requirements from HIP-devices increases as new areas are explored. As demands from the
costumer increases advanced tools have to be used in this process. One such tool, that is
nowadays quite commonly used, is CFD. The challenge is, however, to perform efficient and
trustful simulations on complicated problems. We therefore suggest a project aimed to both make
a CFD-model and thereafter validate it using experiments and analytical models. In this case it
connects to the use of ejectors to achieve a good mixture in the furnace. This is done by means of
a high-pressure motive fluid, in our case argon gas and converging/diverging ducts that promotes
the drag of a secondary fluid. The performance is affected by a whole range of different
parameters in the device, for example mixing, turbulence, friction and separation. Attention is put
on quality and trust of the CFD simulations.
The objective in the thesis is to examine the flow through an ejector with the means of CFD and
thereafter improve the design and efficiency of the device. The main tasks will be:

Steady-state analysis of the flow field in a 2D ejector

Validation using experiments

Comparison with an analytical model

Optimization of design to achieve the best performance for given operating conditions
and in that way optimize the equipment’s efficiency by geometric variation and entrainment ratio
analysis.
Suitable background

Master of science program in Mechanics, Physics, Mathematics or similar

Skilled in fluid dynamics and numerical analysis

Accustomed with CFD products
Location
The thesis will take place at the Avure office in Västerås and is aimed for one or two persons.
Contact person Avure
Per Burström, PhD
R&D Engineer, CFD
[email protected]
For more information about our products please visit our homepage at http://industry.avure.com.