The heat parameters, the thermoanemometric flow-meter （TAF） errors and the experimental characteristics have been defined. The results of experiments were conducted with the help of physically-informational models a...The heat parameters, the thermoanemometric flow-meter （TAF） errors and the experimental characteristics have been defined. The results of experiments were conducted with the help of physically-informational models allowing to realize all major thermal methods and their inherent informative options. The metrological evaluation was made and the sensitivity to the consumption of gas and liquid have been defined, their static and dynamic errors, followed by the comparison of costs according to these criteria. The developed method provides accurate measurement of volumetric flow of motor fuel 1.0-1.5% at heater temperature measurement accuracy of 1%.展开更多
The mixing effectiveness of the airflow between the inner and outer bypass inlets of a Rear Variable-Area Bypass Injector(RVABI)is the key to the afterburner performance of variable cycle engines.This paper describes ...The mixing effectiveness of the airflow between the inner and outer bypass inlets of a Rear Variable-Area Bypass Injector(RVABI)is the key to the afterburner performance of variable cycle engines.This paper describes an optimized RVABI design based on an alternating area regulator to improve the velocity/temperature uniformity of the incoming flow at the afterburner.Compared with a classical RVABI,numerical simulations show that the proposed alternating RVABI performs better in terms of thermal mixing efficiency and total pressure loss in different variable cycle engine modes.Both the increasing air contact area between the inner and outer bypass of alternating structure RVABI,and a larger streamwise vortex in the inner bypass inlet due to the proposed alternating lobe structure in the RVABI contribute to the significantly increase of mixing effectiveness.Besides,the alternating regulator induces strong streamwise vortex,which helps to improve the airflow mixing with its vortex-induced velocity.The interaction between the streamwise vortex and azimuthal vortex further promises the velocity/temperature uniformity after the RVABI.With the increase of alternating lobe’s height ratio,the covering area of the streamwise vortex and the azimuthal vortex is enlarged,which further enhances the thermal mixing efficiency of the RVABI.This design gives an insight into the future design and optimization of RVABI.展开更多
文摘The heat parameters, the thermoanemometric flow-meter （TAF） errors and the experimental characteristics have been defined. The results of experiments were conducted with the help of physically-informational models allowing to realize all major thermal methods and their inherent informative options. The metrological evaluation was made and the sensitivity to the consumption of gas and liquid have been defined, their static and dynamic errors, followed by the comparison of costs according to these criteria. The developed method provides accurate measurement of volumetric flow of motor fuel 1.0-1.5% at heater temperature measurement accuracy of 1%.
基金This study was supported by the National Science and Technology Major Project,China(No.J2019-III-0016-0060)。
文摘The mixing effectiveness of the airflow between the inner and outer bypass inlets of a Rear Variable-Area Bypass Injector(RVABI)is the key to the afterburner performance of variable cycle engines.This paper describes an optimized RVABI design based on an alternating area regulator to improve the velocity/temperature uniformity of the incoming flow at the afterburner.Compared with a classical RVABI,numerical simulations show that the proposed alternating RVABI performs better in terms of thermal mixing efficiency and total pressure loss in different variable cycle engine modes.Both the increasing air contact area between the inner and outer bypass of alternating structure RVABI,and a larger streamwise vortex in the inner bypass inlet due to the proposed alternating lobe structure in the RVABI contribute to the significantly increase of mixing effectiveness.Besides,the alternating regulator induces strong streamwise vortex,which helps to improve the airflow mixing with its vortex-induced velocity.The interaction between the streamwise vortex and azimuthal vortex further promises the velocity/temperature uniformity after the RVABI.With the increase of alternating lobe’s height ratio,the covering area of the streamwise vortex and the azimuthal vortex is enlarged,which further enhances the thermal mixing efficiency of the RVABI.This design gives an insight into the future design and optimization of RVABI.
