Industrial Furnace Technology

Contact person Furnace mechanics: Dr.-Ing. Wolfgang Lenz
Contact person Combustion and Burner Technologies: Nico Schmitz
Contact person Low CO2 process heating: Dr.-Ing. Christian Schwotzer

Areas of research

The core of the activities in this research group is formed by process optimization and process development in the sector of the metal-working industry. To improve the energy and resource efficiency of thermotechnical plants like industrial furnaces, a profound understanding of flow and heat transfer phenomena is essential. The processes are investigated using physical and numerical models. To do this, a number of hot and cold test stands are available and equipped with extensive measurement instrumentation. Apart from that, empirical and analytical modeling as well as simulations based on Computational Fluid Dynamics (CFD) are used. The combination of experimental and numerical investigations allows for a comprehensive representation of the physical phenomena. The research is focused on the following areas:

Industrial furnaces aerodynamics:

  • Hot gas ventilators for high temperature applications
  • Heat introduction into industrial furnaces, direct (gas fired) or indirect heating (gas or electrically heated radiant tubes)
  • Conditions of heat and mass transfer on constructional elements of industrial furnaces
  • Nozzle assemblies for furnaces with high convective heat transfer (chamber furnaces, strip flotation furnaces, etc.)
RWTH-FB5-029
Physical modell of a strip cooling line ( photographer: Martin Braun)

Process gas furnaces:

  • Optimization of gas exchange strategies
  • Control of process gas exchange
  • Development of metal oxide sensors

Combustion:

  • Construction and optimization of burners
  • Direct Flame Impingement (DFI)
  • Flameless combustion (FLOX)
  • Combustion under oxygen deficiency conditions to reduce oxidation of copper and steel
  • Combustion diagnostics using OH* visualization and laser induced fluorescence (LIF)

Modelling and simulation:

  • Recrystallization and grain growth of copper and brass
  • Fluid-Structur-Interaction: effects of fluid flow and thermotechnical phenomena on load and furnace housing
  • Combustion in different applications

Another still emerging research topic are hybrid heating concepts. Most of the industrial furnaces are using fossile fuels, especially natural gas, oil or coal. Against the background of the so called “Energiewende” (energy transition) conventional fuels shall be substituted more and more by electrical power from renewable sources and therefore contribute to the stability of the electrical grid (power to heat). To implement these changes, systematic research and development of new innovative concepts for thermotechnical plants and industrial furnaces is needed.

Ongoing research projects

Defined setting of heat transfer profiles in spray nozzle fields for optimization of heat treatment in continuous strip plants (AiF IGF)

Increasing the thermomechanical stability of cross-flow fans for use in thermoprocessing plants (AiF IGF)

Development of a novel, flexible machining process for the production of quartz glass components (AiF ZIM)

Thermal and material effects of hydrogen atmospheres during heat treatment (AiF IGF)

Possible applications of decentralized oxygen generation in industrial furnaces (AiF IGF)

Thermal characterization of surface contacts (AiF IGF)

Tailored Heating in Hot Forming (AiF IGF)

Renewable residential heating with fast pyrolysis bio-oil – Residue2Heat (EU H2020)

Development of innovative regeneratively heated radiant heating tubes for use in heat treatment plants with small installation space (AiF ZIM)

New tunnel kiln concept for energy-efficient firing of bricks (AiF IGF)

Development of an interactive batch planning system for plasma nitriding plants (AiF ZIM)

Increased surface area and service life of radiant heating pipes through the use of structured sheets (AiF IGF)

Completed research projects