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为了研究磁流体能量旁路超燃冲压发动机(AJAX)的混合燃烧性能,采用三维数值方法,分别对磁流体发电器作用区和化学反应区进行模拟.在其他条件不变的情况下,改变磁场强度和载荷因子从而改变燃烧室的入口条件,得到不同磁流体条件下的混合效率和燃烧效率.计算结果显示:随着磁场强度的增加和载荷因子的减小,混合效率都提高了,最多提高了11.4%,在热离解不明显的燃烧室前半段,燃烧效率也都有所提高;在燃烧室后半段,不出现热离解时燃烧效率最多提高6.5%,此时磁流体装置的引入可使燃烧室长度缩短25%,可降低飞行器的几何尺寸,减轻飞行器质量;出现热离解时,燃烧效率会有所降低甚至低于无磁流体作用时的情况,因此应尽量避免磁场强度过大或载荷因子过小引起燃烧室入口静温过高造成热离解降低燃烧效率.
In order to study the mixed combustion performance of magnetic fluid energy bypass scramjet (AJAX), a three-dimensional numerical method was used to simulate the active region and the chemical reaction region of the MRF respectively. Under other conditions, the magnetic field Intensity and load factor to change the inlet conditions of the combustion chamber to obtain the mixing efficiency and combustion efficiency under different magnetic fluid conditions.The calculation results show that the mixing efficiency increases with the increase of magnetic field strength and load factor, 11.4%. In the first half of the combustion chamber where thermal dissociation is not obvious, the combustion efficiency also increases. In the latter half of the combustion chamber, the combustion efficiency does not increase up to 6.5% when thermal dissociation occurs. At this time, the introduction of the magnetic fluid device The length of the combustion chamber can be shortened by 25%, which can reduce the geometric size of the aircraft and reduce the mass of the aircraft; when thermal dissociation occurs, the combustion efficiency will be reduced or even lower than that when no magnetic fluid is used. Therefore, Too small a load factor causes the thermal entrance of the combustion chamber to become too hot, causing thermal dissociation to reduce the combustion efficiency.