Objectives

Aerodynamic design and analysis are key tasks in fan development. Classical semi-empirical aerodynamic design and performance prediction methods increasingly compete with optimization based methods. Steady-state CFD simulation represent the current state-of-the-art for performance prediction and design optimization. Despite the undoubted progress in the development of computational methods, the experimental build and test of new designs remains indispensable. Experimental test data is not only a form of design verification, but provides an insight into the dominant loss mechanism at plat within the blade-to-blade passage.

Following Fan 2015, the Fan 2018 Fan Aerodynamics Track provides a platform for the presentation and discussion of new computational and experimental methods that advance the state-of-the-art in air movement fan design. Papers combining new computational methods and experimental results will be particularly welcome. The track includes papers specifically focused on the following topics:

Particular emphasis will be given to the following topics.

• Development of analytical and computational methods
• Application of analytical and computational methods for fan analysis, design and optimization
• Inverse Design
• Fan Design for improved efficiency
• Experimental methods in fan analysis and design
• Validation and verification
• Physics of aerodynamic losses
• Unsteady CFD simulations including LES, hybrid RANS/LES, LBM and aero-elastic.
• Impact of emerging technologies on aerodynamic fan design

CFD: computational Fluid Dynamics
LES: Large eddy simulation
LMB: Lattice-Boltzmann Method

Compliance with Legislation & Regulations

Legislative and regulatory pressures are significantly higher at this time than has been the historic norm within the fan industry, and a driver for development of new technology within the fan industry.

Harmonization of Fan Standards Worldwide

Different countries or regions have different standards for fan testing or fan applications. A harmonization of these standards can increase their acceptance and a more efficient use.

Operation and Maintenance Considerations

A shift to maintenance-on-demand in a quest to minimize plant down-time and in so doing maximize availability has resulted in a shift towards more design-for-maintenance and increasingly sophisticates condition monitoring systems.

Motors & Drive

Efficiency, affordability and reliability of the motors used to drive fans are critical, with motors the subject of efficiency legislation and drives becoming more effective as the technology they employ matures.

Specialized Fans for different applications

Extremely hot or cold environments need fans with special materials. Some fans transport abrasive media, too. These fans have special shapes and coatings to withstand the additional forces.

Retrofit and Upgrading existing fan installations

The enhancement and upgrading of existing plant and equipment, at least partly driven by constantly evolving legislative and regulatory requirements presents its own unique set of challenges, associated with working within the constraints of an existing system.

Fan System Effect

As the performance of fans and their associated systems is improved, their susceptibility to the effects associated with the systems within which they are installed increases. The method by which system effect on fans may be assessed and minimized is a distinct area of competence that had developed rapidly over recent years.

Energy related topics (e.g. air curtain effectiveness)

An air curtain is an example of an energy related product including a fan as a main component. Only the combination of the fan, the system and the environment together can work as a good energy related product.

Case studies (e.g. tunnel ventilation)

The planning and designing process of ventilation systems in tunnels, buildings, mines, wind tunnels etc. is risky. The identification of drawbacks and uncertainties in the design is necessary to find simple and robust solutions.

Improving Fan Sizing/Selection

Improved design tools give a selection of fan type and size for a specific load as well as advantageous layouts.

Fan Retrofits and Replacements for Efficiency

Old fans are less efficient than newer ones. A better aerodynamic design combined with an adjusted control system can increase the overall system efficiency

Structural mechanical aspects (vibration, fatigue and flutter, preventive maintenance, condition monitoring)

Vibrations can cause fatigue and noise during fan operation. The monitoring of vibrations or phenomena like flutter are important for prevention actions and maintenance ranges.

Transient phenomena

Phenomena, which appear and disappear can cause noise or influence the aerodynamics of the fan. The transient phenomena are difficult to measure or simulate. Due to the design of circumferential fans or axial fans with dissymmetric inflow characteristics, these phenomena cannot be avoided.

Lessons learnt

The combination of different fans in a system can cause unwanted interactions, which influence the efficiency, volume flow or fatigue. Strategies and actions can help to avoid or deal with these problems.

Scaling methods

Huge fans like wind tunnels, mines and tunnel fans are too large to allow a direct efficiency measurement. The efficiency gap between model and prototype of axial as well as centrifugal fans are predicted with scaling or prediction methods which determine changes in relative roughness, Reynolds number etc.

Market surveillance

The introduction of a worldwide market surveillance can guarantee that products, which are placed on the market, are monitored. The authoritiers have the necessary powers, resources and knowledge to perform their functions, which are reviewed and assessed periodically. A best practice example of market surveillance is the pump industry.