Overview

Mentor Graphics plays a pioneering role in the simulation of airflow in and around buildings by delivering high-quality analysis software for designers. The result is powerful Computational Fluid Dynamics (CFD) software called FloVENT, which predicts 3D airflow, heat transfer and contamination dispersion in both internal and external environments.

FloVENT’s fast and easy-to-use menu system is designed specifically for engineers involved in the design and optimization of heating, ventilating and air conditioning (HVAC) systems.

FloVENT can be applied to buildings of all types and sizes.

• atriums, shopping malls and office buildings
• theatres, airport terminals, storage facilities and warehouses
• telephone exchanges and data centres
• passenger comfort in vehicles
• air quality and contaminant control in laboratories, research facilities, hospitals and underground car parks.

Airflow modeling gives engineers the luxury to consider several design options in the minimum amount of time. As a result, the final design is not based on a tentative approach, but is a result of a professional design process considering several options and selecting the optimum solution. This can save on capital and running costs, save time on correcting mistakes further down the design route and save time on commissioning.

Whether you choose to license FloVENT for inhouse use or to employ Mentor Graphics’ FloVENT airflow modeling consultancy, you can meet the daily challenges of predicting airflow patterns and thermal effects, maximizing contamination control, and reducing operating costs more confidently and productively than ever before.

"Using FloVENT we can review a number of design scenarios early in the development cycle, which helps to reduce bottlenecks and improve engineering performance"
Ian Matthews, Engineer, Buro Happold

Why Perform Airflow Modeling?

No matter how complex your airflow application is, modeling enables you to understand it more comprehensively through the medium of virtual reality and computer 3-D animation. As a result, you can:

• Thoroughly understand the multiple, interacting factors that influence airflow.
• Optimize design calculations of air volume and set point temperatures to enable dramatic savings in capital investment and system operating costs.
• Confidently predict and eliminate airflow problems or hazards early in the design process before building or renovation begins.
• Effectively troubleshoot airflow problems or hazards in and around existing facilities to ensure fast resolution with minimum downtime.
• Dramatically reduce the time and cost while dramatically increasing the value of physical airflow testing and measurement.

Model Creation

SmartParts

FloVENT features the most complete and technically advanced model creation environment for airflow modeling design. Models that range in scale from diffusers, heat exchangers and enclosures are assembled quickly from a complete set of SmartParts (intelligent model creation macros) that are supplied with FloVENT. SmartParts capture modeling expertise that has been developed within Mentor Graphics over the past 15 years to streamline model creation, minimize solve times and maximize solution accuracy.

Integration with CAD

FloVENT also features the industry’s best solution for integration with CAD software. Native data from Pro/Engineer, Autodesk inventor, Solidworks and other CAD software can be imported into FloVENT. Unlike other CAD to analysis interoperability solutions, FloVENT automatically prepares the geometry for efficient and accurate analysis.

Grid

FloVENT grid is structured-Cartesian - the most stable and numerically efficient type of grid available. The ability to localize is also included for finer resolution where it is needed, minimizing solution time and avoiding the penalty of grid cells that “bleed”.

Grid in FloVENT is associated with SmartParts and is generated as part of the model assembly process with refinement under user control. This methodology is intuitive and straightforward enabling engineers to focus on design rather than analysis.

Gridding is instantaneous and reliable in FloVENT as compared to traditional tools that require significant time and expertise to master. Finally, FloVENT is the only analysis software with object-associated grid that eliminates re-gridding for each model modification.

SOME KEY FEATURES

• CAD-style, mouse-driven drawing board using simple draw, drag and drop operations to create and manipulate geometry
• Explorer-style project manager with drag-and-drop functionality
• Complete set of SmartParts (intelligent model creation macros)
• Multi-level SmartParts (compact and detailed representations in a single object)
• Structured-Cartesian grid that can be “localized” and nested to minimize solve times and enable multi-scale modeling
• Full control of grid constraints for fine, local and global refinement
• Object-associated grid that combines model creation and grid generation into a single step

Solver and Design Optimization

Automatic Sequential Optimization

SmartPart-based modeling and structuredcartesian grid enable a feature called ‘automatic sequential optimization’ that is unique to FloVENT. This allows users to specify a design goal and then let FloVENT do the hard work of finding the right combination of design variables that meet the goal. Common applications of this feature include optimization of diffuser locations and discharge velocities as well as other design scenarios.

Design of Experiments Parametric Studies

As an alternative to automatic sequential optimization, a design of experiments (DoE) can be constructed that will automatically analyze the full range of all possible combinations of parametric variations. These models can be solved on a distributed network of computers using the unique ‘Volunteer’ solution technology.

Solver

For over 15 years, the FloVENT solver has specifically addressed heating, ventilation and air conditioning (HVAC) applications. The solver, based on a cartesian gridding system, delivers the most accurate results possible and the fastest solution time per grid cell. Massive disparency in geometric length scales are resolved using the unique ‘localized-grid’ technique which allows for integrally matched, nested, non-conformal grid interfaces between different parts of the solution domain. The conjugate nature of heat transfer is concurrently solved using a preconditioned conjugate residual solver together with a flexible cycle multi-grid solution technique. Pragmatic, unique and accurate solution termination criteria produce useful results in engineering, not academic, time scales.

Transient Analysis

The powerful transient analysis capabilities in FloVENT also allow for prediction of a number of different transient behaviours. For example an accurate prediction of smoke or contaminant dispersion can be calculated both internally and externally. Various scenarios can be investigated by changing the concentration of the smoke or gas in relation to elapsed time

SOME KEY FEATURES

• Concurrent solution for convective, conductive and radiative heat transfer
• Fully automatic radiation exchange and view factor calculation
• Automatic solar loading boundary conditions
• Automatic treatment for heat gains and losses through glazing
• Solution termination optionally based on convergence of user defined monitor points
• Multi-fluids capability
• Ability to simulate either turbulent or laminar flow (turbulent models - revised algebraic, LVEL algebraic, Standard k-e, revised k-e)
• Definition in transient variation in terms of linear ramping, power increase, exponential increase, sinusoidal, periodic or imported .csv pointwise variations

Visualization

Results

The FloVENT visualization toolset is developed specifically to maximize productivity of engineers. Fully rendered models, 3D flow animation and tools for dynamic manipulation of temperature and flow results, enable engineers to pinpoint thermal and ventilation issues and visualize design improvements quickly and effectively. Texture mapping and video output enables powerful communication of design concepts with non-technical colleagues and customers.

Study of cleanroom cross contamination

Tracking cleanroom moisture condensation

SOME KEY FEATURES

• Particle animation and streamlines to visualize complex, 3D airflow
• Contour animation to visualize heat transfer paths
• Isosurfaces and surface temperatures
• Airflow representation by vectors or ribbons colored by temperature or speed
• Easy output of flow animations such as video (AVI format)
• Dynamic particle tracking allowing a better understanding of complex flows
• Image texturing for photo-realistic visualization

Airflow Modeling Consultancy, Training and Support

Occupancy Comfort

Contaminant Tracing

External Flow

Data Centers

Comprehensive Training and Support

Contaminant tracking within a cleanroom/pharmaceutical facility

"We have found that applying airflow modeling technology in the design of our clients’ cleanrooms has proved beneficial for reduction of capital costs, verification of design and optimization of operations, and has led to new design innovations, such as new concepts for 300mm manufacturing environments"
Douglas Cansdale Cleanroom Design Specialist, CH2MHill/IDC