EXPERIMENTAL THERMAL AND FLUID SCIENCE
·
2024
·
IF 2.8
Gabriel Silva Dias,Fábio Antônio da Silva Mota,Lihan Fei,Yingtao Wu,Mingyang Liu,Chenglong Tang,Fernando de Souza Costa
The combination of high-concentration solutions of hydrogen peroxide, known as High Test Peroxide (HTP), with the green fuel composed of tetramethylethylenediamine, dimethylaminoethanol, and methanol (TMEDA/DMEA/MeOH, 1:1:1 vol%), catalyzed by 1 wt% of copper chloride dihydrate, has significant potential for space hypergolic propulsion applications in terms of performance and safe operation. Besides the well-known and mature propulsion systems adopting liquid and solid propellants, gel propellants also present interesting characteristics that can be better explored to enable the creation of alternative propulsive systems. The present work employed HTP at 98 wt% with 6 wt% of fumed silica as a gelling agent to create gelled HTP (GHTP). Droplets of the green fuel impinged on a layer of GHTP placed over a glass slide, acting as a solid oxidizer, mimicked an element of a new hybrid gel/liquid hypergolic propulsion system. Data from infrared and visible light cameras enabled a detailed analysis of the dynamics of a reactive droplet impinging on a gelled oxidizer wall, as well as the heat release, ignition, and flame spread of the hypergolic GHTP/green fuel pair under open-air conditions. The heat release was observed to be distributed across concentric annular areas for both the fuel surrogate and the fuel with catalyst, before and after ignition, demonstrating a strong correlation with non-reactive droplet fluid dynamics, which was corroborated by spread diameter analysis processed from visible image data. Vapor and Ignition Delay Times (VDT and IDT) were found to be as low as 4 and 17 ms, respectively, for the highest droplet impact velocity and catalyst concentration. The reaction rate in the gas phase, considering the flame spread area, showed a dependency of both impact velocity and catalyst concentration, with the latter exhibiting a more pronounced and clear effect. The surface temperature ranges where first vaporization and ignition occurred were 60 °C ∼ 70 °C and 120 ∼ 170 °C, respectively, which is close to the boiling point of methanol and the auto-ignition temperature of TMEDA. This finding, along with the chemical mechanisms in the gas phase related to the presence of a catalyst in the fuel, may be important for hypergolic ignition. The relatively low ignition temperatures and the short ignition times represent additional advantages of the present hypergolic combination for propulsion applications.
研究领域:
航空航天工程
·
推进剂化学
✓ 已验证
产品关联
DOI
高影响因子
ACTA ASTRONAUTICA
·
2024
·
IF 3.1
Zilong Zhao,Jun Chen,Zhichao Yang,Chenbin Zhao,Yuxin Wei,Weidong Wang,Hong Qiao,Wen Ao
Mg-based nanofluid fuel is a promising fuel for propulsion system in Mars exploration . In this study, Mg-based nanofluid fuel were prepared by one-step method, and the effect of Mg(magnesium) content, Mg size(68 μm,110 μm,175 μm), and oleic acid (OA) on droplet ignition and combustion under the atmosphere of 90 % CO 2 and 10 % O 2 were investigated. According to the TG-DSC results, 68 m Mg particles under CO 2 had the highest exothermic efficiency of 4472 J/g. The combustion of Mg/OA/kerosene droplets consists of five stages: ignition, d 2 -law combustion, micro-explosion, vapor flame extinguishment, and agglomerate explosion. The ignition delay time of Mg (68 μm, 5 %)/kerosene is 0.045s, which is half that of kerosene (0.0890s). The agglomerates explode violently and emit a brilliant white light at the end of the Mg-based nanofluid fuel combustion . The explosive effect of Mg agglomerates diminishes as the Mg content increases. The rate of combustion decreases with increasing particle size. In the sample with added oleic acid, Mg (68 μm, 5 %)/OA/kerosene shows the best combustion rate of 0.6320 mm 2 /s. Finally, a numerical model for the combustion of Mg-based nanofluid fuel droplets is proposed. The predictions are within 2 % of the experimental results. The findings are expected to explore future in-situ utilization of CO 2 on the Mars surface .
研究领域:
能源科学
·
材料科学
✓ 已验证
DOI
高影响因子
ACTA ASTRONAUTICA
·
2024
·
IF 3.1
Yi-min Luo,Teng Ma,Hong-wei Zhao,Nian Yang,Sen Xu,Wen-fang Zheng
Slow-burn propellants are crucial for aerospace advancement. This study focuses on the development of slow-burn propellants by replacing a small amount of AP (3–9 %) with various amine-based burning rate suppressants (BRSs). The consistency between thermal analysis and combustion test results indicates a direct link between the main exothermic decomposition process and combustion performance, with changes in onset temperature positively correlated with decreases in combustion parameters. Upon adding 3 % oxamide, the onset temperature of the main decomposition peak in DSC shifted backward by 16.2 °C, significantly higher than the formulations containing ammonium sulfate at 2.6 °C and ammonium oxalate at −0.8 °C. As the content of oxamide further increased from 3 to 9 %, the ignition delay time increased simultaneously by 0.300–1.638 s, atmospheric burning rate decreased by 14.01–45.45 %. These values represent the maximum among formulations with the same content of the BRSs, mainly attributed to its higher heat absorption capacity .
研究领域:
航空航天工程
·
材料科学
✓ 已验证
DOI
高影响因子
ACTA ASTRONAUTICA
·
2024
·
IF 3.1
Haoqiang Sheng,Xiaobin Huang,Yuan Ji,Jie Zhang,Wenbin Hu,Zeming Ji,Xiangzhao Wang,Miaoshen He,Hong Liu
Controllable hydrocarbon fuel combustion and combustion path adjustment are effective but difficult approaches to achieve reliable ignition under extreme conditions. However, the effective mechanism to control the combustion characteristics of hydrocarbon fuels is still unclear. In this study, the fuel (Fuel 6) based on free radical relay combustion (FRRC) significantly expands the ambient temperature-based ignition limits of pure fuel and shows a weak temperature correlation with ignition delay time. In addition, Fuel 6 still has a 100 % ignition probability at 50 kPa (the corresponding ignition limit flight altitude increased from 0.9 km above sea level to 5.4 km). Gaussian simulations show the thermodynamic feasibility of FRRC and prove the relay effect. According to kinetic analysis , the combustion reactions can be adjusted based on FRRC and exhibit three types of oxidation reactions, of which the reaction activation energies are all lower than those of the oxidation reactions of pure fuel. Furthermore, the results of in-situ Fourier transform infrared spectroscopy are consistent with the kinetic analysis based on thermogravimetric and differential thermogravimetric studies. The investigation of the combustion control mechanism under extreme conditions helps to broaden the ignition limit of the aviation engine combustor and to significantly improve the accurate control level of ignition under extreme conditions, providing theoretical support for solving the ignition problems of advanced aviation engines under extreme conditions.
研究领域:
能源科学
·
化学动力学
·
航空工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2023
·Vol. 148
·期 17
·8849-8859
·
IF 4.4
Liu Long,Tian Yanan,Bai Ruibing,Li Yue,Su Ze,Yao Yuan,Zhang Yanqiang
IL-H 2 O 2 bicomponent hypergolic propellant is a new type of green and environmentally friendly hypergolic propellant, but its ignition delay time needs to be further reduced. In this paper, an iodine-containing ionic liquid of 1-methyl-4,5-diiodoimidazolium iodide ([Dmim]I) was synthesized and applied to the spontaneous combustion system of methylimidazolium borane (MIMB) and H 2 O 2 . When a small amount of [Dmim]I was added, the spontaneous combustion of MIMB was enhanced and the flame color becomes brighter as well as the ignition delay time can be reduced from 250 to 109 ms; the accelerator of [Dmim]I had less effect on the maximum specific impulse of MIMB, but the combustion mechanism of MIMB in 95% H 2 O 2 was changed may be by lowering the Gibbs free energy of the dehydrocoupling reaction between the H 2 O 2 and the MIMB. Thermal behavior of MIMB, [Dmim]I, and MIMB containing 2 mass% [Dmim]I were studied by thermogravimetric analysis. The decomposition temperature of MIMB is greatly delayed after adding 2 mass% of [dmim]I, and the maximum temperature delay is about 30 °C; the thermal decomposition of MIMB includes two thermal mass loss processes and the corresponding decomposition activation energy are increased with the addition of [Dmim]I; these indicate that MIMB is compatible with [Dmim]I without oxidizing agent, and [Dmim]I has a stabilizing effect on MIMB.
研究领域:
推进剂化学
·
材料科学
✓ 已验证
DOI
高影响因子
FUEL
·
2016
·
IF 3.611
Jingshan Wang,Xibin Wang,Xiangshan Fan,Kangkang Yang,Yingjia Zhang
Kinetic analyses were performed based on the experimental results of ignition delay times of 2-methyltetrahydrofuran (2-MTHF) using shock tube technique at temperatures of 1050–1800 K, equivalence ratios of 0.5–2.0, fuel mole concentrations of 0.25–1.0%, and pressures of 1.2–10 atm. A new kinetic model of 2-MTHF oxidation named Mech III was established according to the analysis of simulation using two published models (Mech I from Ravi Fernandes group and Mech II from Battin-Leclerc group) and the experimental data in this work. Comparison between simulation and experimental data indicated that Mech II shows remarkable under-prediction while Mech I gives a good agreement with ignition delay times under most conditions except for underprediction on fuel-rich mixtures at relative low temperature around 1250 K. Sensitivity analysis indicated that both models underestimated ignition delay times for the reactions of C 0 -C 4 molecules, so Mech III was formed by introducing such reactions and can demonstrate improved simulation performance under all conditions. Reaction pathway analysis of Mech III showed that 2-MTHF is mainly consumed through fuel decomposition at high temperatures (around 1550 K), and H-atom abstraction reactions at lower temperatures (around 1250 K), respectively. The comparative experimental and kinetic study between 2-MTHF and 2-methylfuran (MF) indicated that 2-MTHF has higher ignition delay times under the same conditions in this work, while the disparity decreases as the temperature increases, and 2-MTHF produces less soot precursors under high temperature conditions.
研究领域:
化学动力学
·
燃烧科学
✓ 已验证
产品关联
DOI
高影响因子
Energetic Materials Frontiers
·
2025
·
IF 3.9
Su-hang Chen,Jie Zhang,Kui Tang,Xi Chen,Jia Zhao,Tuan Zhao,Bin Zhang,Kang-zhen Xu
Microwave ignition (MWI) technology enables synchronized large-area multi-point ignition, multi-pulse operation, higher combustion temperature and efficiency, and dynamic thrust modulation through microwave field adjustments compared to conventional electric ignition methods. However, MWI application is still limited by the absence of a microwave-responsive ignition agent. Herein, A series of nano-titanium/copper ferrite/potassium perchlorate ( n- Ti-CFO/KP (0∼40%)) microwave-sensitive agents were successfully synthesized via electrostatic spraying, where KP enhances combustion, while CFO acts as both catalyst and microwave sensitizer. MWI results demonstrate that n- Ti-CFO/KP (10%) exhibits the shortest ignition delay time (IDT) by 6.34 ms, owing to its high chemical reactivity and the high microwave absorption of Ti, CFO. Combustion analysis suggests that n- Ti-CFO/KP (40%) composite achieves 10-fold combustion enhancement over KP-free ignition agents by a peak pressure of 552.2 kPa and combustion rate of 221.4 m·s -1 , while n- Ti-CFO/KP exhibits the combustion flame temperature of 1250 °C compared to n- Ti-CFO by 700 °C. This remarkable improvement is attributed to the synergistic catalytic activation and combustion - supporting effects of CFO. Furthermore, n- Ti-CFO/KP (10%) exhibits comparable combustion and sensitivity performance to conventional agents ( μ- Ti/KP and B/KNO 3 ). The n- Ti-CFO/KP (10%) shows its main exothermic peak at 310 °C, significantly lower than the 550 °C peak observed for μ- Ti/KP, as well as the excellent catalytic decomposition effect of CFO on KP was further confirmed, where the low reaction temperature can shorten the microwave dielectric heating time. The synergistic effect and combustion intensification result from the coupled interaction between the microwave thermal characteristics of n- Ti-CFO and low-temperature oxygen release kinetics of KP. This coupling achieves significantly reduced MWI delay and enhanced energy release rates, thereby overcoming traditional combustion's reliance on high-temperature conditions. This result provides a new insight into the design of pyrotechnics and propulsion for fast plasma generation and microwave combustion.
研究领域:
材料科学
·
燃烧学
·
能源化学
·
推进技术
·
功能材料
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2024
·
IF 5.3
Nan Liu,Qi Chen,Xianwu Jiang,Jie Chen,Lidong Zhang,Jiaying Pan,Haiqiao Wei,Xingqian Mao
This work presents a three-stage hybrid nanosecond discharge (NSD) and direct current (DC) discharge assisted n -C 5 H 12 /O 2 /N 2 ignition with lower discharge energy and higher energy efficiency. The reaction rate coefficients between O 2 (a 1 Δ g ) and n -C 5 H 12 are updated by mass/Master equation simulation. The promotive ignition enhancement via reaction channel O 2 (a 1 Δ g ) + n -C 5 H 12 → C 5 H 10 + H 2 O 2 in the hybrid NSD/DC discharge is demonstrated. The results show that the ignition delay time of the three-stage hybrid plasma assisted ignition is 1–2 orders of magnitude shorter than that of the two-stage hybrid discharge when the reduced electric field strength in the DC discharge stage is over 10 Td. Meanwhile, the plasma-enhanced energy efficiency of three-stage hybrid discharge increases. This improved efficiency on ignition enhancement is due to the kinetic enhancement by the electronically excited species and radicals (O 2 (a 1 Δ g ), O( 1 D), N 2 (B) and O). The kinetic and thermal effects by plasma are effectively intergated to enhance ignition. However, more discharge energy deposited in the vibrationally excited states N 2 ( v ) in the two-stage hybrid discharge is less efficient on ignition enhancement due to the thermal contribution via vibrational-translational relaxation. In the aspect of NO x /N 2 O emissions, reduction efficiency of the three-stage hybrid discharge is two times higher than that of the two-stage hybrid discharge. By controlling the N/N( 2 D) production pathway e + N 2 → e + N + N( 2 D), the three-stage hybrid discharge reduces NO x and N 2 O production by 61.1 % and 90 %, respectively. The results show that the ignition delay time is non-monotonically dependent on the discharge pulse number. There exist optimal pulse number, reduced electric field and effective threshold power density of DC discharge to achieve maximum ignition enhancement and low NO x /N 2 O emissions. This study provides valuable insights into the use of NSD/DC hybrid discharge technology in advanced engines to achieve energy-efficient ignition enhancement and reduce NO x /N 2 O emissions.
研究领域:
能源科学
·
环境科学
·
化学动力学
✓ 已验证
产品关联
DOI
高影响因子
Chemistry-An Asian Journal
·
2019
·Vol. 14
·期 12
·2122-2128
·
IF 3.698
Zhenyuan Wang,Guangxing Pan,Binshen Wang,Ling Zhang,Weiwei Zhao,Xing Ma,Jichuan Zhang,Jiaheng Zhang
Graphical Alternative hypergolic fuels : A family of novel azide-functionalized cation-based hypergolic ionic liquids were designed and synthesized from cost-effective materials. These ionic liquids displayed excellent properties including low melting points, high thermal stability, low viscosities, and unique hypergolic reactivity, demonstrating their promise as potential alternative hypergolic fuels to toxic and volatile hydrazine derivatives. Hypergolic ionic liquids (ILs) have shown a great promise as viable replacements for toxic and volatile hydrazine derivatives used as propellant fuels, and hence, have attracted increasing interest over the last decade. To take advantage of the reactivity and high energy density of the azido group, a family of low-cost and easily prepared azide-functionalized cation-based ILs, including fuel-rich anions, such as nitrate, dicyanamide, and nitrocyanamide anions, were synthesized and characterized. All the dicyanamide- and nitrocyanamide-based ILs exhibited spontaneous combustion upon contact with 100 % HNO 3 . The densities of these hypergolic ILs varied in the range 1.11–1.29 g cm −3 , and the density-specific impulse, predicted based on Gaussian 09 calculations, was between 289.9 and 344.9 s g cm −3 . The values of these two key physical properties are much higher than those of unsymmetrical dimethylhydrazine (UDMH). Among the studied compounds, compound IL-3b, that is, 1-(2-azidoethyl)-1-methylpyrrolidin-1-ium dicyanamide, shows excellent integrated properties including the lowest viscosity (30.9 M Pa s), wide liquid operating range (−70 to 205 °C), shortest ignition-delay time (7 ms) with 100 % HNO 3 , and superior density specific impulse (302.5 s g cm −3 ), suggesting promising applications with potential as bipropellant formulations.
研究领域:
材料科学
·
燃料化学
·
航天推进剂
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMBUSTION AND FLAME
·
2023
·
IF 4.4
Jinhu Liang,Ruining He,Shashank S. Nagaraja,A. Abd El-Sabor Mohamed,Haitao Lu,Yousef M. Almarzooq,Xiaorui Dong,Olivier Mathieu,William H. Green,Eric L. Petersen,S. Mani Sarathy,Henry J. Curran
2,3-Dimethyl-2-butene (TME) is a potential fuel additive with high research octane number (RON) and octane sensitivity ( S ), which can improve internal combustion engine performance and efficiency. However, the combustion characteristics of TME have not been comprehensively investigated. Thus, it is essential to study the combustion characteristics of TME and construct a detailed chemical kinetic model to describe its combustion. In this paper, two high-pressure shock tubes and a constant-volume reactor are used to measure ignition delay times and laminar flame speeds of TME oxidation . The ignition delay times were measured at equivalence ratios of 0.5, 1.0, and 2.0 in “air”, at pressures of 5 and 10 bar, in the temperature range of 950 – 1500 K. Flame speeds of the TME/ “air” mixtures were measured at atmospheric pressure, at a temperature of 325 K, for equivalence ratios ranging from 0.78 to 1.31. Two detailed kinetic mechanisms were constructed independently using different methodologies; the KAUST TME mechanism was constructed based on NUIGMech1.1, and the MIT TME mechanism was built using the Reaction Mechanism Generator (RMG). Both mechanisms were used to simulate the experimental results using Chemkin Pro. In the present work, reaction flux and sensitivity analyses were performed using the KAUST mechanism to determine the critical reactions controlling TME oxidation at the conditions studied.
研究领域:
燃料化学
·
燃烧科学
✓ 已验证
DOI
高影响因子
Defence Technology
·
2023
·
IF 5.1
Chao Wang,Ying Liu,Mingze Wu,Jia Li,Ying Feng,Xianjin Ning,Hong Li,Ningfei Wang,Baolu Shi
A novel design of micro-aluminum ( μ Al) powder coated with bi-/tri-component alloy layer, such as: Ni–P and Ni–P–Cu (namely, Al@Ni–P, Al@Ni–P–Cu, respectively), as combustion catalysts, were introduced to release its huge energy inside Al-core and promote rapid pyrolysis of ammonium perchlorate (AP) at a lower temperature in aluminized propellants. The microstructure of Al@Ni–P–Cu demonstrates that a three-layer Ni–P–Cu shell, with the thickness of ∼100 nm, is uniformly supported by μ Al carrier (fuel unit), which has an amorphous surface with a thickness of ∼2.3 nm (catalytic unit). The peak temperature of AP with the addition of Al@Ni–P–Cu (3.5%) could significantly drop to 316.2 °C at high-temperature thermal decomposition, reduced by 124.3 °C, in comparison to that of pure AP with 440.5 °C. It illustrated that the introduction of Al@Ni–P–Cu could weaken or even eliminate the obstacle of AP pyrolysis due to its reduction of activation energy with 118.28 kJ/mol. The laser ignition results showed that the ignition delay time of Al@Ni–P–Cu/AP mixture with 78 ms in air is shorter than that of Al@Ni–P/AP (118 ms), decreased by 33.90%. Those astonishing breakthroughs were attributed to the synergistic effects of adequate active sites on amorphous surface and oxidation exothermic reactions (7597.7 J/g) of Al@Ni–P–Cu, resulting in accelerated mass and/or heat transfer rate to catalyze AP pyrolysis and combustion. Moreover, it is believed to provide an alternative Al-based combustion catalyst for propellant designer, to promote the development the propellants toward a higher energy.
研究领域:
材料科学
·
燃烧与推进
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
COMBUSTION AND FLAME
·
2025
·
IF 6.2
Xiaoyuan Chen,Xi Chen,Bin Zhang,Tuan Zhao,Jia Zhao,Kangzhen Xu,Suhang Chen
Microwave ignition technology holds transformative potential in multi-point simultaneous uniform ignition for propulsion systems and energy conversion, attributable to its non-intrusive energy delivery and rapid response characteristics, yet it faces challenges in igniting metallic fuels like aluminum (Al) particles inert to microwaves. To address this critical problem of microwave energy coupling inefficiency in Al, interfacial layers of PF (C 8 H 12 ClNO 2 and CF 3 (CF 2 ) 7 CH 2 CH 2 SH) and APTES (C 9 H 23 NO 3 Si) were constructed to introduce chemical bonding and electrostatic adsorption on the Al surface, followed by inducing CUFO (CuFe 2 O 4 ) dielectric interface anchoring and forming Al@PF@CUFO and Al@APTES@CUFO. This construction of core/shell not only shortens the mass and heat transfer distance but also enhances the interfacial polarization, leading to a strong response to microwaves. Microwave ignition analysis indicates that Al@APTES@CUFO (23.41 ms) exhibits a shorter ignition delay time compared to Al@PF@CUFO (29.51 ms), which can be attributed to the superior bridging capability and rapid decomposition of APTES. APTES not only shortens mass and heat transfer pathways but also facilitates rapid microwave energy absorption by Al/CUFO under microwave irradiation, generating localized hotspots and accelerating the ignition reaction kinetics. Furthermore, Al@PF@CUFO reveals a 327% increase in combustion rate compared to Al@APTES@CUFO, attributed to the fluorination reaction induced by PF decomposition and carbon catalysis derived from the decomposition of PDA. These findings establish dielectric interface engineering as a paradigm-shifting approach to overcome microwave ignition barriers in metallic fuels, with implications for next-generation microwave-controlled solid propellants, pyrotechnics, explosives, etc.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）