Development of a soot concentration estimation library for industrial combustion applications using Lagrangian parcel tracking

Soot emissions from combustion devices are known to have harmful effects on the environment and human health. This project leverages existing knowledge in soot modelling and soot formation fundamentals to develop a stand-alone, computationally inexpensive soot concentration estimator to be linked to CFD simulations as a post-processor. The estimator consists of a library generated using the hystereses of soot-containing fluid parcels, which relates soot concentration to the aggregated gas-phase environment histories to which a fluid parcel has been exposed. The estimator can be used to relate soot concentration to computed parcel hystereses through interpolation techniques. The estimator shows the potential ability to produce accurate predictions with very low computational cost in laminar coflow diffusion flames. Results also show that as flame data representing a broader set of conditions is added to the library, the estimator becomes applicable to a wider range of flames.

Development of a soot concentration estimation library for industrial combustion applications using Lagrangian parcel tracking

Soot emissions from combustion devices are known to have harmful effects on the environment and human health. This project leverages existing knowledge in soot modelling and soot formation fundamentals to develop a stand-alone, computationally inexpensive soot concentration estimator to be linked to CFD simulations as a post-processor. The estimator consists of a library generated using the hystereses of soot-containing fluid parcels, which relates soot concentration to the aggregated gas-phase environment histories to which a fluid parcel has been exposed. The estimator can be used to relate soot concentration to computed parcel hystereses through interpolation techniques. The estimator shows the potential ability to produce accurate predictions with very low computational cost in laminar coflow diffusion flames. Results also show that as flame data representing a broader set of conditions is added to the library, the estimator becomes applicable to a wider range of flames.

Development of a soot concentration estimator for industrial combustion applications

Soot emissions from combustion devices are known to have adverse effects on the environment and human health. Thus, the development of techniques to reduce soot formation and emissions remains an important goal of researchers and industry. This study leverages existing knowledge in soot modelling and soot formation fundamentals to develop a stand-alone, computationally inexpensive soot concentration estimator, to be linked to CFD simulations as a post-processor. The estimator was developed using fluid parcel tracking techniques that can track entire history to which a particle or fluid parcel has been exposed. Preliminary results suggest that the estimator is capable of predicting peak and emitted soot volume fractions in atmospheric pressure flames.

Development of a soot concentration estimator for industrial combustion applications

Soot emissions from combustion devices are known to have adverse effects on the environment and human health. Thus, the development of techniques to reduce soot formation and emissions remains an important goal of researchers and industry. This study leverages existing knowledge in soot modelling and soot formation fundamentals to develop a stand-alone, computationally inexpensive soot concentration estimator, to be linked to CFD simulations as a post-processor. The estimator was developed using fluid parcel tracking techniques that can track entire history to which a particle or fluid parcel has been exposed. Preliminary results suggest that the estimator is capable of predicting peak and emitted soot volume fractions in atmospheric pressure flames.

Закономерности трения многоуровневых композиционных материалов, содержащих высокодисперсные частицы фуллереновой сажи

The paper presents the results of tribological studies of carbon fiber reinforced polymer filled with fullerene soot nanoparticles. It is shown that the dry friction coefficient of the materials does not change when the fullerene soot concentration increases up to 4wt%, but an increase in the friction force occurs due to the forces of intermolecular attraction, the resultant of which monotonically increases.

Soot Formation and Emission From Jet A-1 and a 30% HEFA Blend in a Multisector Combustor at Realistic Operating Conditions

The production and emission of soot from Kerosene JET-A1 and a blend of a different JET-A1 and 30% HEFA was investigated in a realistic multisector combustor of Rolls-Royce Deutschland. Soot concentration measurements were performed at the exit as well as in the optically accessible primary zone of the combustor. There, information of soot mass concentration is available from measurements using Laser induced incandescence and Laser extinction. At the exit of the combustor, soot particles were measured with a scanning mobility particle sizer. This resulted in particle size distributions from which soot number and mass concentrations were calculated. Within the pressurized combustor, low load points, scaled cruise and high load points were operated. For the investigated operating range which reaches to ∼50% of max pressure but preserves engine AFR, up to 75% reduction of both soot particle mass and number EI were observed for the HEFA blend in part load and 50% at the scaled high-power condition. However at the end of the primary zone, a reduction increasing with soot concentration and fuel load was recorded. This guides attention to the different oxidation characteristics for the fuels in the investigated combustor. Accordingly, larger particles were consistently measured at the exit for the HEFA blend.

An Artificial Neural Network for the Low-Cost Prediction of Soot Emissions

Soot formation in combustion systems is a growing concern due to its adverse environmental and health effects. It is considered to be a tremendously complicated phenomenon which includes multiphase flow, thermodynamics, heat transfer, chemical kinetics, and particle dynamics. Although various numerical approaches have been developed for the detailed modeling of soot evolution, most industrial device simulations neglect or rudimentarily approximate soot formation due to its high computational cost. Developing accurate, easy to use, and computationally inexpensive numerical techniques to predict or estimate soot concentrations is a major objective of the combustion industry. In the present study, a supervised Artificial Neural Network (ANN) technique is applied to predict the soot concentration fields in ethylene/air laminar diffusion flames accurately with a low computational cost. To gather validated data, eight different flames with various equivalence ratios, inlet velocities, and burner geometries are modeled using the CoFlame code (a computational fluid dynamics (CFD) parallel combustion and soot model) and the Lagrangian histories of soot-containing fluid parcels are computed and stored. Then, an ANN model is developed and optimized using the Levenberg-Marquardt approach. Two different scenarios are introduced to validate the network performance; testing the prediction capabilities of the network for the same eight flames that are used to train the network, and for two new flames that are not within the training data set. It is shown that for both of these cases the ANN is able to predict the overall soot concentration field very well with a relatively low integrated error.

Numerical Study on Air Egress Velocity of Ancillary Room Pressurization Systems in Apartment Fires

In this study, numerical simulations were performed on the air egress velocity of pressurization systems in an ancillary room when a fire occurred in an apartment house. The relationship between the air supply flow rate of a damper and air egress velocity at a fire door is predicted to be linear. Additionally, a minimum flow rate of the damper, which meets national fire safety standards for air egress velocity, i.e., 0.7 m/s can be estimated. Air egress velocity at the fire door is analyzed according to the supply air direction and installation height of the damper. When the damper has an upward supply air direction and is installed at a high level, the egress velocity at the top section of the fire door is larger, whereas the soot concentration at the ancillary room is lower than when the supply direction of the damper is downward. Therefore, it is found that increasing the air egress velocity at the top section of the fire door helps to efficiently prevent the inflow of smoke.