Experimental and computational analysis has been carried out by many researchers on supersonic cavity flow,but detailed analysis based on Rossiter’s model still requires some insight.In the current study an open rect...Experimental and computational analysis has been carried out by many researchers on supersonic cavity flow,but detailed analysis based on Rossiter’s model still requires some insight.In the current study an open rectangular cavity with a length to depth ratio of 2(L/D=2)and Mach number at the inlet as 1.71,was considered as a baseline configuration for experimental analysis.Statistical techniques such as power spectral density(PSD),correlation,and overall sound pressure level(OASPL)were carried out on the unsteady pressure data,to analyze the aero-acoustic flow physics.High-speed schlieren images were processed to obtain spatially coherent modes by proper orthogonal decomposition(POD).The analysis was extended for different dimensions of subcavities on the aft,floor,and front wall.This detailed analysis of these configurations with different dimensions and combinations revealed the various flow features and mode frequencies in supersonic cavity.As the front wall subcavity act as a passive control device,reducing the overall sound pressure level inside the cavity whereas,the aft wall subcavity acts as a passive resonator with distinct harmonic fluidresonant modes,a similar phenomenon was observed for floor subcavity at different locations.A novel method was employed to analyze Rossiter’s model and its applicability in estimating experimental modes was verified,as it accurately predicted the dominant frequencies with a maximum of 2.74% uncertainty among all the configurations.展开更多
MI-Jet or medium independent jet engine is a new conceptual design which can be used in any gaseous atmosphere or in any planets with an ISP greafer than that of the existing rocket engines.MI engine's thermodynam...MI-Jet or medium independent jet engine is a new conceptual design which can be used in any gaseous atmosphere or in any planets with an ISP greafer than that of the existing rocket engines.MI engine's thermodynamic concept could be utilized to develop turbojet,ramjet and scramjet engines that can operate in Martian environment with higher ISP.The same concept could be extended for the development of MI-Turbojet,M-Ramjet and MI-Scramjet engine for Earth atmosphere with an ISP as high as 200% of the ISP of existing rocket engines,but less than that of the conventional scramjet or other air-breathing engine.However the operational complexity of the MI-Jet will be significantly lower than that of the existing scramjet engine.展开更多
基金the support provided by the Department of Aerospace Engineering,IIST,Trivandrum,India,in carrying out this research work.
文摘Experimental and computational analysis has been carried out by many researchers on supersonic cavity flow,but detailed analysis based on Rossiter’s model still requires some insight.In the current study an open rectangular cavity with a length to depth ratio of 2(L/D=2)and Mach number at the inlet as 1.71,was considered as a baseline configuration for experimental analysis.Statistical techniques such as power spectral density(PSD),correlation,and overall sound pressure level(OASPL)were carried out on the unsteady pressure data,to analyze the aero-acoustic flow physics.High-speed schlieren images were processed to obtain spatially coherent modes by proper orthogonal decomposition(POD).The analysis was extended for different dimensions of subcavities on the aft,floor,and front wall.This detailed analysis of these configurations with different dimensions and combinations revealed the various flow features and mode frequencies in supersonic cavity.As the front wall subcavity act as a passive control device,reducing the overall sound pressure level inside the cavity whereas,the aft wall subcavity acts as a passive resonator with distinct harmonic fluidresonant modes,a similar phenomenon was observed for floor subcavity at different locations.A novel method was employed to analyze Rossiter’s model and its applicability in estimating experimental modes was verified,as it accurately predicted the dominant frequencies with a maximum of 2.74% uncertainty among all the configurations.
文摘MI-Jet or medium independent jet engine is a new conceptual design which can be used in any gaseous atmosphere or in any planets with an ISP greafer than that of the existing rocket engines.MI engine's thermodynamic concept could be utilized to develop turbojet,ramjet and scramjet engines that can operate in Martian environment with higher ISP.The same concept could be extended for the development of MI-Turbojet,M-Ramjet and MI-Scramjet engine for Earth atmosphere with an ISP as high as 200% of the ISP of existing rocket engines,but less than that of the conventional scramjet or other air-breathing engine.However the operational complexity of the MI-Jet will be significantly lower than that of the existing scramjet engine.
