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Jet-Swirl Injector Spray Characteristics in Combustion Waste of a Liquid Propellant Rocket Thrust Chamber
Published in Dzaraini Kamarun, Ramlah Mohd. Tajuddin, Bulan Abdullah, Engineering and Technical Development for a Sustainable Environment, 2017
Zulkifli Abdul Ghaffar, Salmiah Kasolang, Ahmad Hussein Abdul Hamid
Generally, there exist two types of rocket which are liquid propellant rocket and solid propellant rocket. The liquid propellant rocket is a rocket with the propellants is stored separately as liquids and are injected to the thrust chamber [1]. Liquid propellant rocket are generally used for large rockets such as space launch vehicles and ballistic missiles. Solid propellant rocket are much lighter so they are used in smaller missiles such as air-launched and shoulder-launched missiles. Schematic of one type of liquid propellant rocket (liquid bipropellant rocket) is shown in Figure 13.1.
Studies on the surface of high-performance alloys machined by micro-EDM
Published in Materials and Manufacturing Processes, 2018
Wujun Feng, Xuyang Chu, Yongqiang Hong, Li Zhang
Titanium alloys, stainless steels, and high-speed steels are three types of high-performance alloys that are widely used in the aerospace industry. Titanium alloys are characterized by low density, high-temperature strength, and endurance strength; therefore, they have been used to replace aluminum alloys in fabricating the shells of aircraft engines. Stainless steel is another type of material applied extensively to space launch vehicles and exhaust passages around rocket engines because it possesses good plasticity and toughness. High-speed steel is mainly used in high-speed cutting of aircraft parts because it has high hardness and good wear resistance. In aerospace materials, surface accuracy is extremely important; low-quality surfaces can have serious consequences in many cases. Because the abovementioned three types of materials are difficult to machine, the selection of suitable machining methods for these types of intractable materials must be considered carefully.
Influence of Doped H2O or H2 on Soot Production and Power Capability in the Fuel-rich Gas Generator
Published in Combustion Science and Technology, 2022
Yujun Li, Taichang Zhang, Tao Yuan, Xuejun Fan
In recent years, reusable rocket is a hot spot and a trend of space development at home and abroad, which can greatly reduce the cost of space launch (Donahue et al. 2008). The rocket engine system is the core of the rocket, and the gas generator cycle is one of the main cycle modes of the rocket engine. At present, the most popular reusable Falcon 9 rocket uses the Merlin series engine which employs the rich-fuel gas generator (Vozoff and Couluris 2008). For the LOX/kerosene rocket engine with gas generator cycle, the high concentration of soot and the large area of coke deposition in the pipeline (Edwards 2006) have adverse effects on the rocket engine system and structure, thus reducing the performance and operation life of the rocket engine. It is not conducive to the reuse of the rocket. Therefore, it is necessary to study influential factors on the formation mechanism as well as the amount of soot and coke deposition during the combustion of aviation kerosene. The relevant studies have been performed. In soot formation mechanism, Hai Wang (Wang 2011) reviewed the research status of sooting processes in the past 20 years, including soot precursor formation, particle nucleation, and mass/size growth. Formation mechanism of coke deposition, including the chemical processes of coke deposition formation and the factors affecting deposition content has been extensively studied (Beaver et al. 2005; Heneghan and Zabarnick 1994; Spadaccini, Sobel, Huang 2001). In the gas generator carbon deposition, the effects of mixture ratios and combustion pressure on soot formation and deposition characteristics were studied in a fuel-rich LOX/kerosene gas generator and a GOX/kerosene gas generator (Feng et al. 2017; Lausten, Rousar, Buccella 1985; Lawver 1983). The carbon deposition and soot formation characteristics of RP-3 kerosene under certain conditions were studied (Abdalla et al. 2020; Pei and Hou 2016), which indicates different types of kerosene also affect carbon deposition and the formation of soot. In addition, the development of numerical calculation also enables researchers to further study the characteristics of coke and soot (Foelsche et al. 1994; Yu and Lee 2007). For some hydrocarbon fuels, such as gasoline, the effects of the addition of alcohol and ether on the soot formation and combustion properties of the fuel were studied (Liu et al. 2018; Zhu et al. 2020), but as far as we know the additional components were rarely involved to suppress sooting in aviation kerosene and oxygen combustion. Moreover, influence of the additive on the power capability of combustion products of the gas generator were rarely studied.