A scramjet engine combustion efficiency measure system was designed.The combustion efficiency was measured by chromatography method,and the results of chromatography method were compared with those of temperature meth...A scramjet engine combustion efficiency measure system was designed.The combustion efficiency was measured by chromatography method,and the results of chromatography method were compared with those of temperature method.The results indicate that the combustion efficiency measured by chromatography method was 80.7%,lower than the combustion efficiency of 84.5%measured by temperature method;the combustion efficiency could be measured more precisely by chromatogram method than by temperature method.The combustion efficiency measure system based on chromatogram method can work well,and thus can be used to measure the combustion efficiency of scramjet engine.展开更多
This work aims at solving the problems of difficult dispersion,easy oxidation and high cost of nano carbon during application,carbon/magnesium aluminate spinel(C/MgAl_(2)O_(4))composite powders were prepared using MgC...This work aims at solving the problems of difficult dispersion,easy oxidation and high cost of nano carbon during application,carbon/magnesium aluminate spinel(C/MgAl_(2)O_(4))composite powders were prepared using MgC2O4·2H2O,MgO2,Al2O3 powder,and Al powder as raw materials by combustion synthesis.The results indicate that with the maximum MgC2O4·2H2O addition of 33.34 mass%,the prepared powder contains 1.17 mass%of carbon and carbon distributes among spinel grains.The MgAl_(2)O_(4)spinel shows both granular and rod-like morphologies.The granular MgAl_(2)O_(4)spinel is generated from mutual diffusion between MgO and Al2O3;while the rod-like MgAl_(2)O_(4)spinel is mainly formed by the vapor-solid growth mechanism from Mg vapor and Al2O3.展开更多
Combustion of biogas in gas turbines is an interesting option for provision of renewable combined heat and power from biomass. Due to an increasing share of fluctuating renewable energies in the power grid(especially ...Combustion of biogas in gas turbines is an interesting option for provision of renewable combined heat and power from biomass. Due to an increasing share of fluctuating renewable energies in the power grid(especially from wind and solar power), flexible power generation is of increasing importance. Additionally, with an increasing share of agricultural and municipal waste in biogas production, biogas composition is expected to be within a broader range. In this paper, the combustion of synthetic biogas(carbon dioxide and methane) in a combustion test rig with a swirl burner and a high pressure optical chamber is researched at different conditions. Results are compared to a CHEMKIN-PRO simulation using a detailed reaction mechanism. The results show that within the researched experimental matrix, stable biogas combustion for gas turbines can be achieved even with significantly changing gas composition and nominal power. Carbon dioxide concentration is varied from 0 to 60%. CO concentrations(normalized to 15% O_2) in the flue gas do not change significantly with increasing carbon dioxide in the fuel gas and, for the researched conditions, stayed below 10 ppm. NO_x concentration is below 10 ppm(normalized to 15% O_2) for pure methane, and is further decreasing with increasing carbon dioxide share in the fuel gas, which is mainly due to changing reaction paths as reaction analysis showed. Thermal load of the combustor is varied from 100% to 20% for the reference gas composition. With decreasing thermal load, normalized carbon monoxide flue gas concentration is further reduced, while NOx concentrations are remaining at a similar level around 5 ppm(normalized to 15% O_2).展开更多
文摘A scramjet engine combustion efficiency measure system was designed.The combustion efficiency was measured by chromatography method,and the results of chromatography method were compared with those of temperature method.The results indicate that the combustion efficiency measured by chromatography method was 80.7%,lower than the combustion efficiency of 84.5%measured by temperature method;the combustion efficiency could be measured more precisely by chromatogram method than by temperature method.The combustion efficiency measure system based on chromatogram method can work well,and thus can be used to measure the combustion efficiency of scramjet engine.
文摘This work aims at solving the problems of difficult dispersion,easy oxidation and high cost of nano carbon during application,carbon/magnesium aluminate spinel(C/MgAl_(2)O_(4))composite powders were prepared using MgC2O4·2H2O,MgO2,Al2O3 powder,and Al powder as raw materials by combustion synthesis.The results indicate that with the maximum MgC2O4·2H2O addition of 33.34 mass%,the prepared powder contains 1.17 mass%of carbon and carbon distributes among spinel grains.The MgAl_(2)O_(4)spinel shows both granular and rod-like morphologies.The granular MgAl_(2)O_(4)spinel is generated from mutual diffusion between MgO and Al2O3;while the rod-like MgAl_(2)O_(4)spinel is mainly formed by the vapor-solid growth mechanism from Mg vapor and Al2O3.
基金the support from the Biofuels Research Infrastructure for Sharing Knowledge (BRISK) 7th Framework Programme to conduct this project (ref. CFU3-01-09-15)supported by funds of the Federal Ministry of Food and Agriculture (BMEL) based on a decision of the Parliament of the Federal Republic of Germany
文摘Combustion of biogas in gas turbines is an interesting option for provision of renewable combined heat and power from biomass. Due to an increasing share of fluctuating renewable energies in the power grid(especially from wind and solar power), flexible power generation is of increasing importance. Additionally, with an increasing share of agricultural and municipal waste in biogas production, biogas composition is expected to be within a broader range. In this paper, the combustion of synthetic biogas(carbon dioxide and methane) in a combustion test rig with a swirl burner and a high pressure optical chamber is researched at different conditions. Results are compared to a CHEMKIN-PRO simulation using a detailed reaction mechanism. The results show that within the researched experimental matrix, stable biogas combustion for gas turbines can be achieved even with significantly changing gas composition and nominal power. Carbon dioxide concentration is varied from 0 to 60%. CO concentrations(normalized to 15% O_2) in the flue gas do not change significantly with increasing carbon dioxide in the fuel gas and, for the researched conditions, stayed below 10 ppm. NO_x concentration is below 10 ppm(normalized to 15% O_2) for pure methane, and is further decreasing with increasing carbon dioxide share in the fuel gas, which is mainly due to changing reaction paths as reaction analysis showed. Thermal load of the combustor is varied from 100% to 20% for the reference gas composition. With decreasing thermal load, normalized carbon monoxide flue gas concentration is further reduced, while NOx concentrations are remaining at a similar level around 5 ppm(normalized to 15% O_2).
