Radix 2 fft algorithms is analyzed , and fixed geometry configuration and blocking floating format of data is used to implement 256 points 12 bit complex numbers fft 并在分析了基2fft算法的基礎上,采用固定幾何結(jié)構和塊浮點數(shù)據(jù)格式,實現(xiàn)了256點12位復數(shù)點的fft運算。
The numerical results of the dispersion relation show some nonlinear effects : for a fixed geometry of a waveguid , beam parameters and plasma density , the increment of the modulation parameter may lead to a slight increment of the operating frequency , however , as the modulation parameter increases further , saturation may occur and the dispersion relations are hard to be separated , it is due to the overmodulation of the microwave power , this phenomenon itself belongs to the nonlinear effects 對于一定的波導、電子注參量和等離子體密度值,等離子體調(diào)制系數(shù)的增加,使工作頻率略微升高。但是,隨著等離子體調(diào)制系數(shù)的進一步增加,色散曲線變得彼此之間不可分辨,可以認為是等離子體的過調(diào)制導致了柵的飽和。這一現(xiàn)象是非線性的,可見,等離子體柵和調(diào)制場中文摘要是非線性關系,等離子體柵是非線性j 。
In this paper , maccormack explicit time - split scheme , baldwin - lomax algebraic turbulent model and two - steps hydrogen - air nonequilibrium chemical kinetics model are employed to simulate the 2 - d flow fields in a fixed geometry scramjet combustor in different injecting way of fuel in different flight conditions . the results show , in the same entrance condition , the operating mode of scramjet combustor is influenced by the control of fuel 本文采用maccormack顯式時間分裂法、 b - l代數(shù)渦粘性湍流模型及氫-空氣兩步非平衡化學動力學反應模型,模擬了在不同的飛行馬赫數(shù)條件下,固定幾何的雙模態(tài)燃燒室在不同供油規(guī)律下的二維燃燒流場。