Article
Thermodynamics
Fuxu Quan, Juntao Chang, Chen Kong, Chengkun Lv, Guangwei Wu
Summary: This study investigates the fuel injection strategy and the effect of supplemental oxygen on the mixing performance in a scramjet combustor through large eddy simulations. The results show that injecting fuel from the upstream nozzle enhances mixing efficiency compared to the downstream nozzle. Additionally, supplementing oxygen at the trailing edge of the strut significantly improves turbulence and enhances fuel and oxidizer mixing.
APPLIED THERMAL ENGINEERING
(2024)
Article
Thermodynamics
A. C. Rajesh, S. Jeyakumar, Kandasamy Jayaraman, Mehmet Karaca, A. Antony Athithan
Summary: The effect of dual cavity locations with strut injection configuration on supersonic flow under reacting conditions is evaluated numerically. The study investigates the shock wave patterns and their association with shear layer mixing features at different locations of the top wall cavity and bottom wall cavity. The flow pattern, static pressure and temperature distributions, and performance analysis of the dual cavity designs associated with the results of the DLR scramjet are analyzed.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Engineering, Aerospace
Sheng-yi Wang, Zhao-bo Du, Wei Huang, Gautam Choubey
Summary: The mixing process between the fuel and air is crucial for the efficient operation of the scramjet engine, and a coaxial injector has been developed and investigated to enhance the mixing process. Numerical approaches have validated the effectiveness of the coaxial injector, showing that it induces a quicker mixing process and has a promising potential for the scramjet engine. The results also indicate that the jet-to-crossflow pressure ratio has a minimal impact on the total pressure recovery coefficient.
AEROSPACE SCIENCE AND TECHNOLOGY
(2022)
Article
Thermodynamics
Wubingyi Shen, Yue Huang, Zongyang Liu, Yancheng You
Summary: The study investigates the mixing and combustion processes of the transverse injector and hypermixer in a Hyshot combustor under different equivalence ratios, revealing significant impacts of interactions between the stream-wise vortex and hypermixer on mixing and combustion efficiencies. As the equivalence ratio increases, the combustor with the hypermixer maintains higher combustion efficiency compared to the one with the transverse injector, which has already switched to the ramjet mode at high equivalent ratios.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Engineering, Aerospace
Gautam Choubey, Malhar Solanki, Tathya Bhatt, G. Kshitij, D. Yuvarajan, Wei Huang
Summary: The major issue in improving the efficiency of the scramjet engine is ensuring adequate hydrogen fuel distribution within the supersonic chamber. The cavity floor injection strategy is a promising approach to keeping the flame stable under a wide range of operational conditions. The simulation results indicate that as the free-stream Mach number rises, the circulations inside the cavity become more intense, resulting in the formation of a stable igniting zone inside the cavity. The effect of different cavity floor length injection on the performance of the combustor has also been explored, with the optimum cavity floor length found to be 45 mm.
Article
Energy & Fuels
Obula Reddy Kummitha, K. M. Pandey
Summary: The global demand for enhanced scramjet engine performance is increasing, with the main challenge being the mixing of fuel and air. Research has shown that using a wavy wall surface and double strut fuel injector can significantly improve mixing efficiency and combustion phenomenon.
Article
Engineering, Aerospace
Lei Shi, Zhaoyang Tian, Chaowu Dai, Wei Zhang, Zheng Wei, Guojun Zhao, Rui Ran
Summary: The study investigates the effect of high mass flow rate rocket jet on flame stability and combustion characteristics in a cavity-based scramjet combustor through ground direct-connect test. The experimental results show that rocket augmentation can effectively improve combustion pressure and thrust, enhance mixing efficiency and combustion stability, and significantly enhance scramjet performance.
AEROSPACE SCIENCE AND TECHNOLOGY
(2023)
Article
Engineering, Aerospace
Wei Wang, Miaosheng He, Hong Liu, Wei Tian, Yan Wang
Summary: Experimental research was conducted to investigate the flow structure of Mach 0.3 and 0.5 inflow over a rectangular cavity and reveal the properties of mass exchange using particle image velocimetry technology. The results showed that increasing Mach number led to decreased growth rate of the cavity shear layer, while the length-to-depth ratio had varying effects on the shear-layer growth rate.
Article
Chemistry, Physical
A. C. Rajesh, S. Jeyakumar, Kandasamy Jayaraman, Mehmet Karaca
Summary: This study investigates the flow performance of a dual wall-mounted cavities in a strut-injector mounted scramjet combustor under steady-state and transient reacting conditions. The research compares two-dimensional Reynolds Averaged Navier-Stokes approach and Delayed Detached Eddy Simulation for computing the steady and unsteady flow characteristics. The results show that the dual cavities arrangement accelerates complete combustion and modifies the flow structures due to intense shock shear layer interactions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Long Gao, Xin Yu, Jiangbo Peng, Ye Tian, Zhen Cao, Fuyu Zhong, Guohua Wu, Minghong Han
Summary: This study investigates the combustion and oscillation behaviors in a hydrogen-fueled cavity-stabilized scramjet combustor using a high-speed PLIF technique. The spatial distribution of the flame structure under different fuel injection conditions is studied. The results reveal the shift in flame peak position downstream of the cavity with increasing injection pressure. The dynamic characteristics of flames under different flow conditions are analyzed, and the correlation between flame features and hydrogen injection conditions is obtained.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Thermodynamics
Qiang Fu, Wenyan Song, Guiqian Jiao
Summary: A series of combustion experiments with kerosene were conducted at Northwestern Polytechnical University's combustion test equipment to investigate the impact of fuel supply control schemes on the location of shock trains. The feasibility of controlling shock train locations by altering fuel supply was also explored. Results showed that different fuel supply schemes resulted in varying speeds and stability of the shock train location. Choosing the combustion chamber wall pressure or the isolator inlet and outlet pressure ratio as controlled parameters was found to be effective in controlling shock train locations, and a closed-loop fuel supply scheme using isolator outlet wall pressure as a controlled parameter achieved a relatively stable shock train location. Additionally, a closed-loop control test with two-point oil supply successfully increased the wall pressure distribution in the combustion chamber expansion section without altering the isolator's wall pressure distribution, which is beneficial for improving engine performance.
Article
Chemistry, Physical
Chen Pu, Guangming Guo, Juliang Han, Sitan Jiang
Summary: This study presents a numerical analysis of the DLR scramjet combustor with different jet schemes of the double-nozzle injector. The optimal jet scheme was found to be an injection angle of 60 degrees and a nozzle spacing of 3 mm, which significantly improved the mixing efficiency. The double-nozzle configuration increased the number of vortexes and created a recirculation zone, while the spacing and direction of the double-nozzle had little effect on the mixing efficiency. The mixing efficiency of the optimal jet scheme for the double-nozzle was improved more significantly at low Mach numbers.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Engineering, Aerospace
Peixi Guo, Xiaowei Li, Nidal H. Abu-Hamdeh, Rashad A. R. Bantan
Summary: The fuel mixing efficiency of a transverse hydrogen multi-jet with lobe-shape nozzle was investigated in this study. The results showed that the application of a 3-lobe injector enhanced fuel mixing and penetration more than other nozzles. Fuel mixing was found to be directly associated with the power of the upstream vortex generated nearby the first injector.
AEROSPACE SCIENCE AND TECHNOLOGY
(2022)
Article
Thermodynamics
Dian Huang
Summary: This study investigates the use of multi-nozzles with varying heights in supersonic combustion chambers of scramjets to enhance fuel mixing and distribution. Computational fluid dynamics is used to analyze the impact of different injector height configurations on supersonic cross-flow and evaluate the flow and fuel mixing efficiency. The findings suggest that multi-jet injectors with different heights can significantly improve fuel mixing downstream.
Article
Energy & Fuels
Gautam Choubey, Malhar Solanki, Om Patel, Yuvarajan Devarajan, Wei Huang
Summary: The shape of the struts significantly affects the combustion mechanism in scramjet engines. Researchers have found that a semi-circular trailing edge half-wedge strut is the most effective configuration, ensuring better combustion performance. Increasing the inward fuel injection angle improves the mixing performance of the two-strut scramjet combustor.
Article
Materials Science, Multidisciplinary
K. Mehar, P. K. Mishra, S. K. Panda
Summary: This study numerically calculated the thermal frequency of a graded nanotube-reinforced composite structure embedded with SMA fiber for the first time, using a micromechanical multiscale finite element material model. The presence of SMA significantly improved the structural stiffness, as indicated by a set of solved numerical examples.
MECHANICS OF ADVANCED MATERIALS AND STRUCTURES
(2021)
Article
Thermodynamics
Pinku Debnath, K. M. Pandey
Summary: The study investigates the effect of modified ejector on detonation combustion wave propagation and propulsion thrust of liquid kerosene and gaseous hydrogen-air mixture. Simulation results show that the thrust force augmentation of hydrogen-air mixture is greater compared to liquid kerosene-air mixture, but the flame propagation velocity is faster for hydrogen-air combustion.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Energy & Fuels
P. Babu Aurtherson, Bhanu Teja Nalla, Karthikeyan Srinivasan, Kulmani Mehar, Yuvarajan Devarajan
Summary: Biodiesel obtained from Prunus domestica kernel oil was synthesized using a two-step transesterification process. Optimization technique was employed to obtain the best process parameters, resulting in high-quality biodiesel that met the standards.
BIOMASS CONVERSION AND BIOREFINERY
(2023)
Article
Energy & Fuels
Yuvarajan Devarajan, Beemkumar Nagappan, Gautam Choubey, Suresh Vellaiyan, Kulmani Mehar
Summary: The results of the study show that adding hydrogen at a rate of 10 lpm can improve the ignition pattern of nonedible mango seed biodiesel and enhance the performance of diesel engines.
Article
Computer Science, Interdisciplinary Applications
Brundaban Sahoo, Kulmani Mehar, Bamadev Sahoo, Nitin Sharma, Subrata Kumar Panda
Summary: In this study, finite element solutions were used to investigate the thermal post-buckling load-bearing strength of functionally graded sandwich shell structures. The results were validated numerically and the impact of various structural parameters on the thermal post-buckling response was studied in detail.
ENGINEERING WITH COMPUTERS
(2023)
Article
Engineering, Multidisciplinary
Akhileshwar Singh, Krishna Murari Pandey, Yogesh Singh
Summary: This study investigates the splitting dynamics of low-viscous fingers inside bifurcating channels through the manipulation of surface wettability. Numerical simulations reveal that the behavior of finger splitting depends on various parameters, including surface wettability, capillary number, viscosity ratio, and surface tension. The findings provide insights into biofluid mechanics and respiratory diseases such as COVID-19.
MATHEMATICAL PROBLEMS IN ENGINEERING
(2022)
Article
Engineering, Multidisciplinary
Durgesh Kumar Mishra, Sumit Bhowmik, Krishna Murari Pandey
Summary: This study discusses the thermal exploration of melting phenomena of beeswax-based phase change material of four different annulus shapes. Numerical investigation on composite-beeswax approach with metal oxide particles revealed improved melting rate and heat transfer. The type of metal oxide particles had minimal impact on melting rate and heat transfer, showing significant enhancements with their presence.
MATHEMATICAL PROBLEMS IN ENGINEERING
(2022)
Article
Engineering, Multidisciplinary
Dipak Debbarma, Krishna Murari Pandey, Abhishek Paul
Summary: This study investigates the enhancement of overall performance in heat sinks by using a double layer structure with protrusions and dimples. Comparisons between microsinks with protruded-dimpled bottom layer and microsinks with protruded-dimpled layers were made, with staggered arrangements showing superior overall performance. The heat sink with both layers protruded and dimpled was found to be optimal, offering excellent thermal performance.
MATHEMATICAL PROBLEMS IN ENGINEERING
(2022)
Article
Materials Science, Multidisciplinary
Bandi Venkata Ramana Reddy, Saikat Ranjan Maity, Lokeswar Patnaik, Sunil Kumar, Krishna Murari Pandey
Summary: Al-6Si-18Pb alloy was fabricated using spray deposition method and warm rolling, and the microstructural change and mechanical properties were studied. The results showed that continuous and discontinuous dynamic recrystallisation occurred in the alloy after warm rolling, resulting in grain refinement. Furthermore, Pb atoms were homogeneously distributed in the Al matrix. The porosity and hardness of the samples were significantly affected after warm rolling.
ADVANCES IN MATERIALS AND PROCESSING TECHNOLOGIES
(2022)
Article
Thermodynamics
Prince Kumar, Ritesh Dwivedi, K. M. Pandey
Summary: This study numerically investigates the impact of different Prandtl numbers on the thermo-hydraulic transport characteristics of a partial porous wavy channel for a laminar flow. The results show that increasing the Prandtl number and Reynolds number leads to an increase in the Nusselt number and enhancement ratio, while the performance factor deteriorates with increasing slab thickness. Additionally, the effect of different Darcy numbers was evaluated.
NUMERICAL HEAT TRANSFER PART A-APPLICATIONS
(2023)
Article
Thermodynamics
Prince Kumar, K. M. Pandey
Summary: This article investigates the effect of varying porous slab thicknesses and Darcy number on the thermohydraulic performance of corrugated channels. The results show that increasing the porous slab thickness and decreasing the Darcy number can enhance the thermal performance but reduce the hydraulic performance.
Article
Thermodynamics
Prince Kumar, Ritesh Dwivedi, Krishna Murari Pandey
Summary: Comprehensive numerical simulations are conducted to investigate the combined effect of three distinct passive techniques on thermo-hydraulic properties and entropy generation in three different wavy channels. It is found that the insertion of porous media between the corrugated walls enhances thermal performance, and the trapezoidal channel shows the highest enhancement by 90%.
HEAT TRANSFER ENGINEERING
(2023)
Article
Computer Science, Interdisciplinary Applications
Akhileshwar Singh, Deepak Kumar Singh, Yogesh Singh, Krishna Murari Pandey
Summary: This paper investigates the influence of viscosity ratio and surface wettability on immiscible viscous fingering instability within a rectangular channel. The findings reveal that higher viscosity ratios lead to increased displacement efficiency, while low viscosity ratios result in necking. The finger-shaped pattern splits into two parts at a wettability of 15 degrees, and no splitting occurs beyond this threshold. Furthermore, a transition from hydrophilic to superhydrophobic wettability abolishes necking and enhances displacement efficiency, with the instability shifting towards the left side.
INTERNATIONAL JOURNAL OF MODERN PHYSICS C
(2023)
Article
Engineering, Multidisciplinary
P. M. Ramteke, K. Mehar, N. Sharma, S. K. Panda
Summary: This paper introduces the finite element solutions for the static deflection and stress values of functionally graded structures considering variable grading patterns and porosity effect, and verifies the accuracy of the numerical solutions by simulation through design software. The comparison and sensitivity behavior of the numerical model are validated by solving different types of numerical examples in the published domain.
Article
Engineering, Civil
Brundaban Sahoo, Kulmani Mehar, Bamadev Sahoo, Nitin Sharma, Subrata Kumar Panda
Summary: This study evaluates the thermal eigenvalue responses of a graded sandwich shell structure under variable thermal loadings, considering temperature-dependent properties. A sandwich panel model is derived and frequency values are computed using finite element formulation, helping to analyze the influence of structural parameters and temperature profiles on natural frequencies. The findings provide insights for designing future graded structures under variable temperature loading.
STRUCTURAL ENGINEERING AND MECHANICS
(2021)
