Biomass can be converted into bio-oil by pyrolysis with high heating and cooling rates. Bio-oil is a crude oil which can be upgraded into high quality liquid fuels, for instance, it can be first gasified into syngas a...Biomass can be converted into bio-oil by pyrolysis with high heating and cooling rates. Bio-oil is a crude oil which can be upgraded into high quality liquid fuels, for instance, it can be first gasified into syngas and then synthesized into methanol, dimethyl ether and so on. Considering bio-oil has high oxygen content, bio-oil gasification without any external supply of oxygen has been performed. The result shows that the mass conversion efficiencies of oxygen and hydrogen elements could reach as high as 85%, but that of carbon is only 55%. Hence, the external oxygen supply should be needed to improve the mass conversion efficiency of bio-oil gasification.展开更多
Shock tubes create simulated blast waves which can be directed and measured lo study blast wave effects under laboratory conditions.It is desirable to increase available peak pressure from ~1 MPa to ~5 MPa to simulate...Shock tubes create simulated blast waves which can be directed and measured lo study blast wave effects under laboratory conditions.It is desirable to increase available peak pressure from ~1 MPa to ~5 MPa to simulate closer blast sources and facilitate development and testing of personal and vehicle armors.Three methods are experimentally investigated to increase peak simulated blast pressure produced by an oxyacetylene driven shock tube while maintaining suitability for laboratory studies.The first method is the addition of a Shchelkin spiral priming section which supports a deflagration to detonation transition.This approach increases the average peak pressure from 1.17 MPa to 5.33 MPa while maintaining a relevant pressure-time curve(near Friedlander waveform).The second method is a bottleneck between the driving and driven sections.Coupling a 79 mm diameter driving section to a 53 mm driven section increases the peak pressure from 1.17 MPa to 2.25 MPa.A 103 mm driving section is used to increase peak pressure to 2.64 MPa.The third method,adding solid fuel to the driving section with the oxyacetylene,results in a peak pressure increasing to 1.70 MPa.展开更多
文摘Biomass can be converted into bio-oil by pyrolysis with high heating and cooling rates. Bio-oil is a crude oil which can be upgraded into high quality liquid fuels, for instance, it can be first gasified into syngas and then synthesized into methanol, dimethyl ether and so on. Considering bio-oil has high oxygen content, bio-oil gasification without any external supply of oxygen has been performed. The result shows that the mass conversion efficiencies of oxygen and hydrogen elements could reach as high as 85%, but that of carbon is only 55%. Hence, the external oxygen supply should be needed to improve the mass conversion efficiency of bio-oil gasification.
文摘Shock tubes create simulated blast waves which can be directed and measured lo study blast wave effects under laboratory conditions.It is desirable to increase available peak pressure from ~1 MPa to ~5 MPa to simulate closer blast sources and facilitate development and testing of personal and vehicle armors.Three methods are experimentally investigated to increase peak simulated blast pressure produced by an oxyacetylene driven shock tube while maintaining suitability for laboratory studies.The first method is the addition of a Shchelkin spiral priming section which supports a deflagration to detonation transition.This approach increases the average peak pressure from 1.17 MPa to 5.33 MPa while maintaining a relevant pressure-time curve(near Friedlander waveform).The second method is a bottleneck between the driving and driven sections.Coupling a 79 mm diameter driving section to a 53 mm driven section increases the peak pressure from 1.17 MPa to 2.25 MPa.A 103 mm driving section is used to increase peak pressure to 2.64 MPa.The third method,adding solid fuel to the driving section with the oxyacetylene,results in a peak pressure increasing to 1.70 MPa.
