Department of Chemical and Process Engineering  ¦ Engler-Bunte-Institute ¦ Deutsch ¦ Legals ¦ Data Protection ¦ KIT
Gasphase
Equilibrium calculator

Please try out our program for calculating the gas phase equilibrium state.
more...

Contact

Engler-Bunte-Ring 7
76131 Karlsruhe 

Building number 40.13.I 

Tel: +49(0)721 608-42571
Fax: +49(0)721 608-47770

E-Mail: Secretariat

Link to page:
Co-operation partner:
Bachelor- and Masterthesis

Current proposals for topics of bachelor- and master thesis you find on the following page.
more ...

Gas combustion
The ongoing demand for a lowering of energy consumption and pollutant emissions calls for persistent optimisation of the burners used to serve the power needs of industrial engineering processes, domestic households and thermal power stations. Owing to the present high standards, a further optimisation can only be achieved through precise knowledge of the relevant physico-chemical processes, i.e. flow, mixing and reaction.

The infrastructure available within the institute allows investigation into the processes mentioned for both laminar and highly turbulent flames with a thermal power of up to 2 MW. The main focus of the research work is investigations into the stability behaviour of turbulent premixed and diffusion flames and the interaction between turbulence and reactions. The measuring equipment used for this ranges from conventional cooled probes through to optical non-contact measuring methods for determining velocity, temperature and mix composition. The data obtained gives a better understanding of the basic mechanisms involved and is increasingly used for developing physical models to describe the individual phenomena.

Detailed description
Additional information on this topic
 

Within this research focus the following research projects are associated:


Methane Engines for Passenger Vehicles
(MetCar)
Contemporary Natural Gas (NG) engines for passenger car applications are not consequently optimized for NG operation. But, due to its high knock resistance, NG offers a high efficiency potential versus gasoline already. EE-C-Methane consists mainly of very neat methane. Therefore, it offers an even higher knock resistance (higher Methane Number) than NG. The higher knock resistance can be transformed into higher efficiency by further increasing the compression ratio (CR) and the boost level of the engine.
In order to exploit the potential and to achieve the high efficiencies, while maintaining drivability and component durability, many aspects need to be considered during the development of a dedicated EE-C-Methane engine, which are content of the described project MethCar. Beside the significant rise of the peak combustion pressure capability of the base engine, volumetric efficiency is going to be increased by means of a new methane direct injection system and a turbo charger with variable turbine geometry, as well as a fully variable valvetrain. Furthermore, the impact of the methane composition (EE-C-Methane) is an important factor for the market introduction potential of methane as automotive fuel. Therefore, in MethCar, the impact of the expected main components of EE-Methane (H2, CH4) and trace elements (as sulfur and compressor oil) on component wear and catalyst efficiency is investigated.
The 3rd innovative element of the study is the investigation how to avoid particle emissions robustly, with the focus on small particles.

Energy Efficient Coil Coating Process
(ECCO)

Coil coating is an important industrial process applied in a major part of industrial steel and metal alloy production and associated with big facilities and large primary energy consumption. A major part of the overall plant size and the energy demand of coil coating facilities is associated with the drying/curing process that occur inside a curing oven, which is the bottleneck concerning the increase of the production capacity. In this drying/curing process, organic solvents are vaporized from the applied liquid coating film and since they are flammable, the usually applied curing ovens with convective air drying technology have to be operated far below the Low Explosive Limit (LEL), due to safety constraints. ECCO proposes a novel solution for the curing oven operation, which can not only drastically increase the compactness and energetic efficiency of the system, but leads to an increased production flexibility due to a fuel-flexible, modular and potentially energetically self-sustainable process. The main idea is to heat the metal strip by IR-radiation and operate the curing oven well above the Upper Explosive Limit (UEL), thus, performing the drying and curing process in an atmosphere mainly consisting of the solvent vapours, which are used as fuel in IR radiant porous burners. This solution leads to a size/ production capacity ratio reduction of 70% and a reduction of investment and operating costs of at least 40% each. Starting from previous activities at TRL 4, an interdisciplinary approach is foreseen, based on advanced-materials, combustion technology and prediction tools for system design/ optimization, with active participation of key industrial stakeholders, to bring this technology to TRL 6 and realize a prototype furnace at industrially relevant size and environment.


TURBOmachinery REtrofits enabling FLEXible back-up capacity for the transition of the European energy system
(TURBO-REFLEX)
Logo

The energy sector accounts for two thirds of the global CO2 emissions and is therefore crucial to ensure future green growth and to achieve the global emission reduction targets. Substantial reduction of CO2 emissions can only be achieved by large scale deployment of renewable energy sources, including in particular the most abundant energy sources, wind and sun. Their intermittent nature however poses significant challenges for the energy system as peak demand from the system and peak production form those intermittent sources do not overlap. As there are no large scale storage solutions available yet, other backup capacities are needed. The installed fossil capacity is large enough to provide this back-up power. However, the plants were designed for baseload operation, which results in increased wear and costs through cyclic operation and unnecessarily high emissions in the start-up phase. Providing technology upgrades to retrofit the installed power plants to enable flexible operation without penalties on life, cost and emissions is an opportunity to quickly provide the necessary backup capacity to keep the energy system stable and resilient and at the same time enabling higher renewable shares.

The mission of TURBO-REFLEX is the development and optimisation of technologies, applicable to a selected set of turbomachinery engine components, which can be used to retrofit existing power plants as well as new machines in order to enable more flexible operation, providing the flexible back-up capacity needed for introducing a larger share of renewables in the energy system. TURBO-REFLEX will assess the impact of such technologies at plant level and prepare the transfer of component technology gains into reduction of both (unplanned and planned) outages and maintenance and operation costs.

The Lean Blow Off (LBO) limit is a significant hurdle to further reduce the part load of gas turbines as the operating zone of the combustor is restricted by the LBO limit. Jet stabilized premixed flames will be forecasted with blow off stability down to 1000°C–1200°C combustion temperature with or without using pilot flames. 1000°C–1200°C combustion temperature would equal emission compliant part load operation down to 20%-25%. Better blow-off stability in the combustor is a prerequisite to running higher load gradients. Therefore, it is expected that jet stabilized premixed flames with better LBO limits will allow also gradients faster than 40MW/min.

EBIvbt at KIT will model the blow-off of jet flames with advanced computational models. These models include basic geometrical parameters like duct diameter and dump ratio, but also the effect of neighboring pilot flames. A 3D simulation model will be developed and experimentally validated at conditions close to the application. The turbulence-chemistry interaction will be captured by two different combustion models. Within both models a transport equation of a reaction progress variable will be solved. The difference between the combustion models is in the source term modelling. In the first model the source term depends on mixture fraction and the progress variable itself. In the second model, which is based on the “turbulent flame speed closure” approach, the source term depends on the laminar flame velocity. So, one can calculate the influence of the stretch and heat loss on the laminar flame speed by simplified 1D modelling. The comparison of the two models to experimental data will show which model is more suitable for the applied boundary conditions.

 

 

Within this research focus in the past the following research projects were associated:


Combustion noise
(CN_Bo)
The current project aims to calculate quantitatively the generation mechanism and propagation of noise caused by turbulent combustion. Fully compressible Large Eddy Simulations (LES), hybrid CFD (Computational Fluid Dynamics)/CAA (Computational Aero-Acoustics) and Direct Numerical Simulation (DNS) are chosen as computational tools. The UTFC combustion model based on a TFC (Turbulent Flame Speed Closure) approach and a FGM (Flamelet Generated Manifold) tabulation procedure has been developed during this project which is used together with compressible LES for turbulent flames. This enables the direct computation of combustion noise from the resolved large scale fluctuations. The DNS will then be applied for investigation of noise within the sub grid scale. The project is connected with three other project partners from TU Darmstadt (Prof. J. Janicka), TU AAchen (Prof. W. Schröder) and TU Berlin (Prof. C.O. Paschereit) who make inkompressible LES, CAA-computation and measurement for the same burner configuration.


More information can be found on this page.


Ignition by mechanical sparks
(MechanicalSparks)
Mechanical sparks as ignition sources play an important role in safety-related assessments of the ignition of combustible mixtures. They are generated, for example, by a short mechanical action on solid materials (grinding, impact, friction). In any case, mechanical sparks are separated, usually glowing individual particles, formed locally at the site of action. Whether or not a particle eventually becomes a spark with sufficient ignition capability depends on the amount of energy deposited initially in the particle and its velocity, as well as the particle material and size. This project investigates the ignition by small hot particles (diameters up to one millimetre) in a combustible atmosphere with varying flow speeds up to a few meters per second. Since the focus of this project lies on a detailed understanding of the ignition process itself, we will primarily look into the combustion related properties of well-defined, spherical particles, but not into the actual process of generating mechanical sparks. The goal is to advance a physical model that describes the ignition event for different particle materials and sizes, spanning the range from quiescent atmospheres to the typical speeds of mechanical sparks. Subject to investigation are hydrogen, ethane and diethylether.

High speed photograps (3.6 kHz) of OH* chemiluminescence (308 nm) of the cw-laser induced ignition (Argon-Ion laser, 4.5W) of a Hydrogen/air mixture (20% Hydrogen in air)