Over the past 20 years, CanmetENERGY has been developing and using Computational Fluid Dynamics (CFD) as a cost-effective tool to analyze energy systems. These systems are used to promote energy efficiency and reduction of emissions in power generation and industrial processes. We have also been utilizing this tool to assist in designing, optimizing performance, resolving operational problems, assessing risks and researching new approaches in energy-related technologies.
Computational Fluid Dynamics (CFD) for Energy Systems
CFD provides a detailed representation of the physical processes inside industrial power or heat equipment such as furnaces, combustors or boilers. For example, figure 1 shows a CFD model of oil combustion in a furnace. Details of the two-phase flow, liquid fuel droplet trajectories, fuel evaporation, combustion, and radiant and convective heat transfer are calculated from basic principles. Comprehensive CFD modeling facilitates understanding the interaction of the various physical phenomena in such a process and provides insights for making improvements. The results of the calculation, such as heat transfer profile to the walls and fuel burn-out, can be visualized graphically as illustrated in figure 1.
Integration with Other Modeling Tools
CFD can be combined with other tools such as process modeling or process control systems to facilitate investigations of a part or an entire process with very detailed information on major components like a furnace or a boiler. Figure 2 provides an example of data from a process model being linked as input to the CFD model; the results are then fed back into the process model to allow multi-component process analysis.
This simulation approach is being developed in collaboration with a metal processing company to assess proposed reconfigurations of furnace operations aimed at reducing SO2 emissions.
In addition to selective academic institutions, CanmetENERGY collaborate with major engineering software suppliers (namely ANSYS and Computational Engineering International ) to advance simulation technologies. Co-operations with Canadian industries have also been sought to evaluate the applicability of such simulation tools to practical engineering problems.
Our activities are also integrated into other CanmetENERGY research programs. They include gasification, oxy-fuel combustion, and energy technologies for high-temperature processes, to complement experimental testing and generate measurement data to enhance model developments and validate modeling theories.
Increasing Accessibility to Computational Fluid Dynamics Modeling
To promote more widespread accessibility to modeling tools, efforts are being made to capture our modeling capabilities and experience in novel software packages designed for users who do not specialize in CFD. One example is CoalFire, shown in figure 3. It is a vertical application designed to simulate the operation of tangentially-fired coal utility boilers. This software presents the user with a customized interface consistent with this type of power boiler for easy specification of operating conditions, burner belt configurations and coal properties. The entire simulation process from computational grid generation to visualization of model results is automated. No adjustment of modeling parameters or solution monitoring is required. The tool is intended to be used by boiler operators and power plant engineers who are generally not experts in CFD. CoalFire can reduce the time requirement for a boiler simulation from weeks to days.
The above appliation was jointly developed with ANSYS Canada Ltd .
A new modeling capability is under development to facilitate investigations and research in areas that can benefit from simulations of a microscopic nature. Figure 4 shows the micro-scale modeling at the atomic level of the electrolyte of a solid oxide fuel cell. Investigations are being conducted to study the relationship between the material nano-structure and the electrochemical reactivity. It is expected that this kind of modeling capability will shed new light in the design of next generation energy systems.
Figure 1: CFD modeling of oil combustion in the pilot scale tunnel furnace at CanmetENERGY. The oil droplet trajectories and medium temperature are shown.
Figure 2: A process model linked to CFD where fluid flow, chemical reactions, and heat transfer in the furnace (yellow) are calculated in detail.
Figure 3: The CoalFire vertical application for tangentially-fired boilers,
Figure 4: A molecular model of the surface of the electrolyte in a solid oxide fuel cell.