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Ammonia (NH3) has gained broad attention as a carbon-free alternative fuel, and its blend with H2 has been especially investigated to mediate the low reactivity of NH3. In the present work, the laminar burning velocities (SL) of NH3+H2+N2+O2 flames were investigated at 1 atm and 298 K, and the oxygen fractions (xO2) in O2+N2 were varied from 0.16 to 0.26, comprising a set of conditions that have not yet been investigated in literature. An updated mechanism was proposed on the basis of our previous published mechanism, which was validated using not only the present data, but also the literature data for NH3 laminar burning velocities and ignition delay times. Over the tested experimental conditions, better predictions were achieved with the updated mechanism. Simulations using the updated and five literature mechanisms were carried out, i.e., mechanisms from Stagni, Bertolino, Shrestha, Konnov, and Mei. The updated and Mei mechanisms reproduce the best the present experimental data. To investigate which reactions influence most the SL increments due to O2 and H2 addition, SL increment parameters were defined for xO2 and xH2 separately. Based on the available experimental data, detailed sensitivity analyses were carried out for these target parameters using the updated and some other mechanisms from the literature. It's found that reactions dominating these parameters could be largely different, thus considerations covering all aspects of SL as well as the SL increment parameters are suggested for the NH3 mechanism validations. Despite the SL increment parameters have different tendencies against the xO2 and xH2 with different reaction sensitivities, local similarities are found if the increments of xO2 and xH2 have been enough refined. Specifically, when the xO2 and xH2 values grow larger, the effects of their increase become well blurred, extending the region of the similar conditions, which is helpful for the determination of inconsistent experimental data.

Abstract Highly thermo-conductive aqueous medium is a crucial premise to demonstrate high-performance thermal-related applications. Graphene has the diamond comparable thermal conductivity, while the intrinsic two-dimensional reality will result in strong anisotropic thermal conductivity and wrinkles or even crumples that significantly sacrifices its inherent properties in practical applications. One strategy to overcome this is to use three-dimensional (3D) architecture of graphene. Herein, 3D graphene structure with covalent-bonding nanofins (3D-GS-CBF) is proposed, which is then used as the filler to demonstrate effective aqueous medium. The thermal conductivity and thermal conductivity enhancement efficiency of 3D-GS-CBF (0.26 vol%) aqueous medium can be as high as 2.61 W m−1 K−1 and 1300%, respectively, around six times larger than highest value of the existed aqueous mediums. Meanwhile, 3D-GS-CBF can be stable in the solution even after 6 months, addressing the instability issues of conventional graphene networks. A multiscale modeling including non-equilibrium molecular dynamics simulations and heat conduction model is applied to interpret experimental results. 3D-GS-CBF aqueous medium can largely improve the solar vapor evaporation rate (by 1.5 times) that are even comparable to the interfacial heating system; meanwhile, its cooling performance is also superior to commercial coolant in thermal management applications.

The mitigation of aerosol pollution is a great challenge in many cities in China, due to the complex sources and formation mechanism of particulate matter (PM) in different seasons. To understand the particular features of pollution in China and formulate different targeted policies, aerosol samples of PM2.5 were collected from January to October of 2018 in Longyou. The temporal profile of the meteorological parameters and the concentrations of water-soluble inorganic ions (WSIs) and organic matter (OM) were characterized. An Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-TOF-AMS) was also applied to further analyze the composition of water-soluble organic carbon (WSOC). The sources of WSOC were resolved by positive matrix factorization (PMF) analysis. The origin of air parcels and potential sources of WSOC were analyzed using a backward trajectory and potential source contribution function (PSCF). Winds from the northeast dominated each sampling period, and the relative humidity did not show a significant difference. The results showed that the proportion of OM in PM2.5 was the highest in summer and decreased in spring, autumn, and winter in turn. Four organic aerosol (OA) factors, including a hydrocarbon-like factor, a coal combustion factor, and two oxygenated OA factors, were identified in the WSOC by means of PMF analysis. The hydrocarbon-like OA (HOA) contributed the majority of the WSOC in summer, while the contribution of the coal-combustion OA (CCOA) increased significantly in winter, suggesting the presence of different sources of WSOC in different seasons. The air parcels from the north of China and Zhejiang province contributed to the CCOA in winter, while those from the marine regions in the south and southeast of China mainly contributed to the HOA during spring and summer. The weighted PSCF (WPSCF) analysis showed that the regions of east Zhejiang province were the main contributors, which means that local and regional emissions were the most probable source areas of WSOC. It implied that not only were the emissions control of both local and regional emissions important but also that the transport of pollutants needed to be sufficiently well accounted for to ensure the successful implementation of air pollution mitigation in Longyou.

The optimization of multiple factors for gasification performance using a 3D CFD model with advanced sub-models for single-stage drop tube coal gasification was compared with experimental results. A single-stage down-drop gasifier with multiple coal injectors and a single oxygen injector at the top of the gasifier was investigated at different temperatures and O2/coal ratios. A finite rate/eddy dissipation (FR/ED) model was employed to define the chemical reactions. Kinetic data for the various reactions were taken from previous work. The realizable k–ε turbulent model and Euler–Lagrangian framework were adopted to solve the turbulence equations and solid–gas interaction. First, various preliminary reactions were simulated to validate the reaction model with experimental data. Furthermore, various cases were simulated at various O/C ratios and wall temperatures to analyze the syngas species, temperature profile in the whole gasifier, exit temperature, carbon conversion, turbulent intensity, and velocity profile. The maximum CO was found to be 75.06% with an oxygen/coal ratio of 0.9 at 1800 °C. The minimum and maximum carbon conversions were found to be 97.5% and 99.8% at O/C 0.9 at 1200 °C and O/C 1.1 at 1800 °C, respectively.

Summary: An active coating based on thermochemical redox reactions is proposed to protect molten salt receivers from solar flux fluctuation. However, appropriate metal oxides working in the temperature range of 530 and 850°C are still missing. Herein, we put forward an oxygen defect engineering strategy to regulate the thermochemical redox temperatures of perovskites. A tunable temperature range of 426–702°C is obtained by BaCo1−xMnxO3−δ (x = 0–0.4). It is found that a raised redox temperature can be obtained with the increase of the oxygen vacancy formation energy. For application, BaCo0.8Mn0.2O3−δ is designed as the active protective coating of a lab-scale receiver, which has a thermal capacity of 82.95 kJ kg−1. The smart coating can slow down the temperature rising rate from 8.5°C min−1 to 3°C min−1 in the first 2 min under strong solar radiation, effectively relieving the thermal shock of the receiver.

Abstract Photothermal membrane distillation (MD) is a promising technology for desalination and water purification. However, solar-thermal conversion suffers from low energy efficiency (a typical solar-water efficiency of ~ 50%), while complex modifications are needed to reduce membrane fouling. Here, we demonstrate a new concept of solar vapour gap membrane distillation (SVGMD) synergistically combining self-guided water transport, localized heating, and separation of membrane from feed solution. A free-standing, multifunctional light absorber based on graphene array is custom-designed to locally heat the thin water layer transporting through graphene nanochannels. The as-generated vapour passes through a gap and condenses, while salt/contaminants are rejected before reaching the membrane. The high solar-water efficiency (73.4% at 1 sun), clean water collection ratio (82.3%), excellent anti-fouling performance, and stable permeate flux in continuous operation over 72 h are simultaneously achieved. Meanwhile, SVGMD inherits the advantage of MD in microorganism removal and water collection, enabling the solar-water efficiency 3.5 times higher compared to state-of-the-art solar vapour systems. A scaled system to treat oil/seawater mixtures under natural sunlight is developed with a purified water yield of 92.8 kg m−2 day−1. Our results can be applied for diverse mixed-phase feeds, leading to the next-generation solar-driven MD technology.

Summary: The formation and bioelectric performance of anode biofilms in microbial electrochemical systems (MESs) are sensitive to oxygen. Investigating the temporal-spatial structure of anode biofilms will help elucidate the interfaces between oxygen and bacteria, thereby facilitating the applications of MESs in wastewater treatment and energy recovery. Here, use of optical coherence tomography, frozen sections, and a microsensor revealed that the aerobic biofilms exhibited a multilayered sandwich structure with a sparse gap between the aerobe- and amphimicrobe-enriched outer layer and the dense exoelectrogen-enriched inner layer, whereas the anaerobic biofilm consisted of only a single dense layer. Our results showed that the inner layer of aerobic anode biofilms performed electricity generation, whereas the outer layer only consumed oxygen. In this case, electron donor diffusion through the outer layer became the limiting factor in electricity generation by the bioanode. Consequently, as the anode biofilms matured, current generation decreased. : Chemical Engineering; Bio-Electrochemistry; Materials Science Subject Areas: Chemical Engineering, Bio-Electrochemistry, Materials Science

An optical method for measuring soot volume fraction, flame temperature, and concentration of combustion products in a diffusion flame based on time-division multiplexed tunable diode laser absorption spectroscopy technique is presented in this article. By moving the slot burner with an electric platform, two-dimensional profile of soot volume fraction, flame temperature, and gas concentrations along the flame sheet with 1-mm spatial resolution were obtained simultaneously. The flame temperature and soot volume fraction were simultaneously on-line monitored using one distributed feedback diode laser with a center wavelength at 1397.83 nm. Tunable diode laser absorption spectroscopy based temperature measurements in the flame were carried out by two-line thermometry of H2O and compared with the thermocouple technique. The attenuation of tunable diode laser intensity caused by soot extinction and gas absorption after transmitting through the diffusion flame was detected. And the soot volume fraction was determined quantitatively with laser extinction based on Rayleigh limit assumption. Two tunable distributed feedback diode lasers with center wavelength at 2001.6 and 2302 nm were used to determine the CO2 concentration and CO concentration, respectively. The experimental results of soot volume fraction, flame temperature, and the mole fraction of combustion products by varying concentrations of CO2 added in the diffusion flame were analyzed.

Starting from a reference and comprehensive chemical mechanism for alkali metal emissions (Glarborg and Marshall, 2005), combined with an hydrocarbon oxidation described with a skeleton mechanism (Kazakov and Frenklach, 1994), reduced and optimized chemical kinetics are derived. The objective is to provide a set of chemical schemes useful for three-dimensional (3D) numerical simulations of alkali metal emissions by pulverized solid-fuel combustion systems. An automated procedure relying on one-dimensional (1D) premixed flames is applied to obtain a combined reduced mechanism, whose performance is then evaluated in one-dimensional strained diffusion flames, micro-mixing based canonical problems and three-dimensional carrier-phase direct numerical simulation (DNS) of coal combustion. Predictions of the reduced mechanism on major sodium species, i.e., Na, NaOH, NaCl and Na2SO4 agree well with that of the detail reference scheme under all the considered conditions. A parametric study with 14 two-dimensional (2D) DNS cases is then performed to better understand the reactive flow properties and estimate the prediction capabilities of the reduced mechanism for various Na/Cl/S ratio in the volatiles. After pursuing the chemistry reduction, a global sodium mechanism with only 9 species and 8 reaction-steps is also discussed. The systematic comparison between the 3D DNS results obtained with the reference chemical scheme against those with the reduced ones confirm the validity of the reduction strategy. A reduction of up to 84% in computational cost is reached with the optimized global scheme, thus allowing for addressing real pulverized-coal combustion systems.

Ti3C2Tx-based aerogels have attracted widespread attention for three-dimensional porous structures, which are promising to realize high-rate energy storage. However, disordered Ti3C2Tx aerogels with highly tortuous porosity fabricated by conventional unidirectional freeze-casting substantially increase ion diffusion lengths and hinder electrolyte ions transport. Herein we demonstrate a new bidirectional ice-templated approach to synthesize porous ordered Ti3C2Tx aerogel with straight and aligned channels, straight and short ion diffusion pathways, leading to better ion accessibility. The aligned Ti3C2Tx aerogel exhibits the high specific capacitance of 345 F g−1 at 20 mV s−1 and rate capability of 52.2% from 10 to 5000 mV s−1. The specific capacitance is insensitive of mass loadings even at 10 mg cm−2 and an excellent power density of 137.3 mW cm–2 is obtained in symmetric supercapacitors. The electrochemical properties of Ti3C2Tx aerogel supercapacitors at sub-zero (to −30 °C) temperatures are reported for the first time. The aligned Ti3C2Tx aerogel delivers temperature-independent rate performance and high capacitance retention (73% at 50 mV s−1 from 25 to −30 °C) due to the unique structure with metallic conductivity.

Slow pyrolysis of a typical high-ash lignite in China was carried out in atmospheres of N2, 20%CO2/N2, 40%CO2/N2, and 60%CO2/N2 in a fixed bed reactor. The evolution of char, tar, and gases in yield and characteristics, and the physico-chemical characteristics of chars in different atmospheres were compared. Results revealed that CO2 almost behaves as an inert gas in the evolution of char and CO before 600 °C. The decrease in char and CO2 yields and the increase in CO yield at temperatures higher than 600 °C are ascribed to the occurrence of char-CO2 gasification. The higher the CO2 level present in the atmosphere, the higher the severity of the gasification becomes. Introducing CO2 into the atmosphere raises tar and water yields but cuts down H2, CH4, and C2H6 yields. The promotion of tar yield results from the higher phenols and aliphatics yields in the presence of CO2. The reduction of H2 yield is associated with the increase in water yield, while the decline of light hydrocarbon gases is connected with the suppression effects of CO2 on methyl decomposition. The role of inherent minerals was also investigated by comparing product yields from raw coal and demineralized coal. The comparison indicated that the char-CO2 gasification rate is sharply reduced to nearly zero without the catalytic effects of calcium, iron, and magnesium minerals. The evolution of tar and light hydrocarbon gases in the CO2-containing atmosphere greatly depends on inherent minerals. Without minerals, tar yield is inhibited in the presence of CO2. In the absence of minerals, CO2 hardly has influences on CH4 and C2H6 yields. Keywords: CO2, Inherent minerals, Lignite, Tar

To improve growth rate of hydroponics lettuce with CO2 aeration, lettuce seeds were mutated by nuclear irradiation (γ rays from 137Cs) and domesticated with high concentration of CO2. When lettuce seeds were mutated with 30 Gy dosage, wet weight of lettuce increased by 22.3% (to 52.24 g) on the 30th day and grana volume in the chloroplasts of leaf cells increased by 244%. After the mutant (irradiated by 50 Gy dosage) was domesticated with elevated CO2 concentration, wet weight of lettuce increased by 74.6% (to 48.7 g) on the 24th day under 3 vol% CO2, compared with wet weight of lettuce under air condition. Results showed that mutagenesis by nuclear irradiation made it possible to improve CO2 fixation rate in lettuce in a gene-modified way. Keywords: Biomass productivity, CO2 domestication, Grana volume, Lettuce productivity

Abstract Electric double-layer capacitors (EDLCs) are advanced electrochemical devices for energy storage and have attracted strong interest due to their outstanding properties. Rational optimization of electrode–electrolyte interactions is of vital importance to enhance device performance for practical applications. Molecular dynamics (MD) simulations could provide theoretical guidelines for the optimal design of electrodes and the improvement of capacitive performances, e.g., energy density and power density. Here we discuss recent MD simulation studies on energy storage performance of electrode materials containing porous to nanostructures. The energy storage properties are related to the electrode structures, including electrode geometry and electrode modifications. Altering electrode geometry, i.e., pore size and surface topography, can influence EDL capacitance. We critically examine different types of electrode modifications, such as altering the arrangement of carbon atoms, doping heteroatoms and defects, which can change the quantum capacitance. The enhancement of power density can be achieved by the intensified ion dynamics and shortened ion pathway. Rational control of the electrode morphology helps improve the ion dynamics by decreasing the ion diffusion pathway. Tuning the surface properties (e.g., the affinity between the electrode and the ions) can affect the ion-packing phenomena. Our critical analysis helps enhance the energy and power densities of EDLCs by modulating the corresponding electrode structures and surface properties.

Printed circuit heat exchanger (PCHE) is a promising regenerative device in the sCO2 power cycle, with the advantages of a large specific surface area and compact structure. Its tiny and complex flow channel structure brings enhanced heat transfer performance, while increasing pressure drop losses. It is, thus, important to balance heat transfer and flow resistance performances with the consideration of sCO2 as the working agent. Herein, three-dimensional models are built with a full consideration of fluid flow and heat transfer fields. A trapezoidal channel is developed and its thermal–hydraulic performances are compared with the straight, the S-shape, and the zigzag structures. Nusselt numbers and the Fanning friction factors are analyzed with respect to the changes in Reynolds numbers and structure geometric parameters. A sandwiched structure that couples two hot channels with one cold channel is further designed to match the heat transfer capacity and the velocity of sCO2 flows between different sides. Through this novel design, we can reduce the pressure drop by 75% and increase the regenerative efficiency by 5%. This work can serve as a solid reference for the design and applications of PCHEs.

For the long-term operation of municipal solid waste incineration (MSWI), online monitoring and feedback control of polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/F) can be used to control the emissions to national or regional standards. In this study, 500 PCDD/F samples were determined by thermal desorption gas chromatography coupled to tunable-laser ionization time-of-flight mass spectrometry (TD-GC-TLI-TOFMS) for 168 h. PCDD/F emissions range from 0.01 ng I-TEQ/Nm3 to 2.37 ng I-TEQ/Nm3, with 44% of values below 0.1 ng I-TEQ/Nm3 (the national standard). In addition, the temperature of the furnace outlet, bed pressure, and oxygen content are considered as key operating parameters among the 13 operating parameters comprising four temperature parameters, four pressure parameters, four flow parameters, and oxygen content. More specifically, maintaining the furnace outlet temperature to be higher than 800 °C, or bed pressure higher than 13 kPa, or the oxygen content stably and above 10% are effective methods for reducing PCDD/F emissions. According to the analysis of the Pearson coefficients and maximal information coefficients, there is no significant correlation between operating parameters and PCDD/F I-TEQ. Only when there is a significant change in one of these factors will the PCDD/F emissions also change accordingly. The feedback control of PCDD/F emissions is realized by adjusting the furnace outlet temperature, bed temperature, and bed pressure to control the PCDD/F to be less than 0.1 ng I-TEQ/Nm3.

Abstract Background The biomass yield of Chlorella PY-ZU1 drastically increased when cultivated under high CO2 condition compared with that cultivated under air condition. However, less attention has been given to the microalgae photosynthetic mechanisms response to different CO2 concentrations. The genetic reasons for the higher growth rate, CO2 fixation rate, and photosynthetic efficiency of microalgal cells under higher CO2 concentration have not been clearly defined yet. Results In this study, the Illumina sequencing and de novo transcriptome assembly of Chlorella PY-ZU1 cells cultivated under 15% CO2 were performed and compared with those of cells grown under air. It was found that carbonic anhydrase (CAs, enzyme for interconversion of bicarbonate to CO2) dramatically decreased to near 0 in 15% CO2-grown cells, which indicated that CO2 molecules directly permeated into cells under high CO2 stress without CO2-concentrating mechanism. Extrapolating from the growth conditions and quantitative Real-Time PCR of CCM-related genes, the K m (CO2) (the minimum intracellular CO2 concentration that rubisco required) of Chlorella PY-ZU1 might be in the range of 80–192 μM. More adenosine triphosphates was saved for carbon fixation-related pathways. The transcript abundance of rubisco (the most important enzyme of CO2 fixation reaction) was 16.3 times higher in 15% CO2-grown cells than that under air. Besides, the transcript abundances of most key genes involved in carbon fixation pathways were also enhanced in 15% CO2-grown cells. Conclusions Carbon fixation and nitrogen metabolism are the two most important metabolisms in the photosynthetic cells. These genes related to the two most metabolisms with significantly differential expressions were beneficial for microalgal growth (2.85 g L−1) under 15% CO2 concentration. Considering the micro and macro growth phenomena of Chlorella PY-ZU1 under different concentrations of CO2 (0.04–60%), CO2 transport pathways responses to different CO2 (0.04–60%) concentrations was reconstructed.

The gasification experiments of coal chars with CO2 were carried out isothermally, with K, Ca, Ni, and Zn chloride catalysts, adopting a thermal gravimetric analyzer (TGA) from 800 to 1100 °C. The kinetic characteristic of the samples were described using the volumetric model (VM), the grain model (GM), and the random pore model (PRM). The morphology patterns of the samples were tested applying X-ray diffraction (XRD) and the catalytic mechanisms concerning the phase changes were proposed. The results confirm that the gasification rate and char reactivities are enhanced by K, Ca and Ni chlorides, while ZnCl2 inhibited the process. The catalysis ability shows the following cation order: Ca > K > Ni > Zn. Among the models described above, PRM was proven to give the best fitting value and hence adopted to kinetics parameters calculation. The activation energies in promoting conditions were lower than that of the uncatalyzed cases. In view of the catalytic mechanism, the K metals tend to form intermediate complexes and repeatedly connect with coal char, while the Ca species may follow the oxidation-reduction mechanism and the Ni metals catalyze the gasification process.

Polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran (PCDD/F) emission characteristics and vapour/particulate phase partitions under three continued operation conditions, i.e. shut-down, start-up and after start-up, were investigated by sampling stack gas. The results indicated that the PCDD/F emission levels were 0.40–18.03 ng I-TEQ Nm−3, much higher than the annual monitoring level (0.016 ng I-TEQ Nm−3). Additionally, the PCDD/F emission levels in start-up were higher than the other two conditions. Furthermore, the PCDD/F congener profiles differed markedly between shut-down and start-up, and the chlorination degree of PCDD/F increased in shut-down and decreased evidently in start-up. Moreover, PCDD/F vapour/particulate phase distributions varied significantly under three transient conditions. The PCDD/F vapour phase proportion decreased as the shut-down process continued, then increased as the start-up process proceeded, finally more than 98% of the PCDD/F congeners were distributed in the vapour phase after start-up. The correlations between log(Cv/Cs) versus log pL0 of each PCDD/F congener in stack gas were disorganized in shut-down, and trend to a linear distribution after start-up. Besides, polychlorinated biphenyl emissions show behaviour similar to that of PCDD/F, and the lower chlorinated congeners have a stronger relationship with 2,3,7,8-PCDD/Fs, such as M1CB and D2CB.

The production rate and yield of ethanol was markedly increased when water hyacinth, pretreated with microwave-assisted dilute acid, was fermented with acclimatized yeasts through simultaneous saccharification and fermentation. Water hyacinth hydrolyzate microwaved with 1% (v/v) dilute sulfuric acid was fermented with the acclimatized mixed yeasts Pichia stipitis and Pachysolen tannophilus at a volume ratio of 1:1. The highest ethanol yield was 0.22 g/g (raw biomass of water hyacinth), which was 76.3% of the theoretical ethanol yield. A maximum ethanol production rate of 0.19 g/(L•h) was obtained after 24 h.

Abstract A new coal staged conversion poly-generation system combined coal combustion and pyrolysis has been developed for clean and high efficient utilization of coal. Coal is the first pyrolysed in a fluidized pyrolyzer. The pyrolysis gas is then purified and used for chemical product or liquid fuel production. Tar is collected during purification and can be processed to extract high value product and to make liquid fuels by hydro-refining. Semi-coke from the pyrolysis reactor is burned in a circulating fluidized bed (CFB) combustor for heat or power generation. The system can realize coal multi-product generation and has a great potential to increase coal utilization value. A 1 MW poly-generation system pilot plant and a 12 MW CFB gas, tar, heat and power poly-generation system was erected. The experimental study focused on the two fluidized bed operation and characterization of gas, tar and char yields and compositions. The results showed that the system could operate stable, and produce about 0.12 m3/kg gas with 22 MJ/m3 heating value and about 10 wt% tar when using Huainan bituminous coal under pyrolysis temperature between 500 and 600 °C. The produced gases were mainly H2, CH4, CO, CO2, C2H4, C2H6, C3H6 and C3H8. The CFB combustor can burn semi-coke steadily. The application prospect of the new system was discussed.

In this study, an 18-steps, 22-species reduced global mechanism for ozone-enhanced CH4/air combustion processes was derived by coupling GRI-Mech 3.0 and a sub-mechanism for ozone decomposition. Three methods, namely, direct relation graphics with error propagation, (DRGRP), sensitivity analysis (SA), and quasi-steady-state assumption (QSSA), were used to downsize the detailed mechanism to the global mechanism. The verification of the accuracy of the skeletal mechanism in predicting the laminar flame speeds and distribution of the critical components showed that that the major species and the laminar flame speeds are well predicted by the skeletal mechanism. However, the pollutant NO was predicated inaccurately due to the precursors for generating NO were removed as redundant components. The laminar flame speeds calculated by the global mechanism fit the experimental data well. The comparisons of simulated results between the detailed mechanism and global mechanism were investigated and showed that the global mechanism could accurately predict the major and intermediate species and significantly reduced the time cost by 72%.

To investigate turbulent reacting flows, a low-Mach number large-eddy simulation (LES) code called ‘LESsCoal’ has been developed in our group. This code employs the Germano dynamic sub-grid scale (SGS) model and the steady flamelet/progress variable approach (SFPVA) on a stagger-structured grid, in both time and space. The method of manufactured solutions (MMS) is used to investigate the convergence and the order of accuracy of the code when no model is used. Finally, a Sandia non-reacting propane jet and Sandia Flame D are simulated to inspect the performance of the code under experimental setups. The results show that MMS is a promising tool for code verification and that the low-Mach-number LES code can accurately predict the non-reacting and reacting turbulent flows. The validated LES code can be used in numerical investigations on the turbulent combustion characteristics of new fuel gases in the future.