Aerospace Science and Technology最新文献

{"title":"Bayesian framework for estimating dynamic stability derivatives in 6-DoF blunt-body entry vehicles","authors":"Ashraf Kassem ,&nbsp;Shafi Al Salman Romeo ,&nbsp;Bipin Tiwari ,&nbsp;Omer San ,&nbsp;Kursat Kara","doi":"10.1016/j.ast.2025.110646","DOIUrl":"10.1016/j.ast.2025.110646","url":null,"abstract":"<div><div>As atmospheric entry vehicles traverse planetary atmospheres, they encounter strongly nonlinear and unsteady aerodynamic loads, leading to uncertain dynamic behavior. Accurate estimation of dynamic stability coefficients is critical for ensuring reliable entry, descent, and landing. This study introduces a Bayesian inference framework coupled with a six-degree-of-freedom dynamic model to estimate these coefficients and quantify their uncertainties using trajectory data. The six-degree-of-freedom model is validated against two benchmark cases, demonstrating strong agreement and establishing its reliability. A two-stage estimation process is employed: (1) Bayesian inference of stability derivatives using Markov Chain Monte Carlo with the No-U-Turn Sampler, based on training cases (<span><math><msub><mrow><mi>α</mi></mrow><mrow><msub><mrow><mi>T</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow></msub><mo>=</mo><msup><mrow><mn>1</mn></mrow><mrow><mo>∘</mo></mrow></msup><mo>,</mo><msup><mrow><mn>5</mn></mrow><mrow><mo>∘</mo></mrow></msup><mo>,</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>∘</mo></mrow></msup><mo>,</mo><msup><mrow><mn>30</mn></mrow><mrow><mo>∘</mo></mrow></msup></math></span>), to recover both static (<span><math><msub><mrow><mi>C</mi></mrow><mrow><msub><mrow><mi>m</mi></mrow><mrow><mi>α</mi></mrow></msub></mrow></msub><mo>,</mo><msub><mrow><mi>C</mi></mrow><mrow><msub><mrow><mi>n</mi></mrow><mrow><mi>β</mi></mrow></msub></mrow></msub></math></span>) and damping (<span><math><msub><mrow><mi>C</mi></mrow><mrow><msub><mrow><mi>m</mi></mrow><mrow><mi>q</mi></mrow></msub></mrow></msub><mo>,</mo><msub><mrow><mi>C</mi></mrow><mrow><msub><mrow><mi>n</mi></mrow><mrow><mi>r</mi></mrow></msub></mrow></msub><mo>,</mo><msub><mrow><mi>C</mi></mrow><mrow><msub><mrow><mi>l</mi></mrow><mrow><mi>p</mi></mrow></msub></mrow></msub></math></span>) coefficients; and (2) prediction at untrained test angles (<span><math><msub><mrow><mi>α</mi></mrow><mrow><msub><mrow><mi>T</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow></msub><mo>=</mo><msup><mrow><mn>2</mn></mrow><mrow><mo>∘</mo></mrow></msup><mo>,</mo><msup><mrow><mn>20</mn></mrow><mrow><mo>∘</mo></mrow></msup></math></span>), via Akima spline interpolation of aerodynamic parameters. Applied to the Genesis sample return capsule, the framework accurately reconstructs training trajectories and captures nonlinear damping effects. Predictions at unobserved conditions maintain strong consistency, with only minor discrepancies near the simulation horizon. These results demonstrate the framework's potential as a robust, uncertainty-aware tool for dynamic stability analysis in atmospheric reentry applications.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"167 ","pages":"Article 110646"},"PeriodicalIF":5.0,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144686403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A quasi-one-dimensional analytical study on the propulsive performance of an oblique detonation engine utilizing different inlets","authors":"Xin Han, Ruofan Qiu, Yancheng You","doi":"10.1016/j.ast.2025.110670","DOIUrl":"https://doi.org/10.1016/j.ast.2025.110670","url":null,"abstract":"Oblique detonation engines (ODEs) utilize standing oblique detonation waves (ODWs) to organize combustion, making them particularly well-suited for hypersonic air-breathing propulsion systems. Previous researches have predominantly concentrated on the flow physics of ODWs, with most experimental and computational studies employing a two-dimensional inlet or omitting the inlet’s compression process. Advanced inlet designs play a crucial role in enhancing the propulsive performance of air-breathing vehicles. This paper presents a comparative analysis of the specific impulse between an ODE vehicle equipped with a three-dimensional inward-turning inlet and one with a two-dimensional inlet at various design points, utilizing a quasi-one-dimensional performance analysis model specifically developed for ODE vehicles. Due to the superior total pressure recovery of the three-dimensional inward-turning inlet, the vehicle equipped with this inlet demonstrates enhanced thrust performance compared to its counterpart with a two-dimensional inlet, except under conditions of lower equivalence ratios (≤ 0.6). This paper systematically investigates the influence of flight altitude, flight Mach number, fuel injection parameters, combustor wedge angle, nozzle expansion area ratio, and nozzle flow model (chemical equilibrium flow and frozen chemistry flow) on the specific impulse of the vehicle, utilizing a quasi-one-dimensional performance analysis model. Among these factors, the flight Mach number, wedge angle, nozzle expansion area ratio, and nozzle flow model have a significant impact on the vehicle’s specific impulse. Additionally, the equivalence ratio and the total temperature of the fuel injection also play an important role in determining the specific impulse. To facilitate the engineering application of the ODE, it is essential to incorporate the three-dimensional inward-turning inlet into the ODE vehicle’s design.","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"26 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2025-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pressure-sensitive paint measurements in transonic backward-facing step flow","authors":"Chia-Ching Wang, Chih-Yung Huang, Kung-Ming Chung","doi":"10.1016/j.ast.2025.110663","DOIUrl":"https://doi.org/10.1016/j.ast.2025.110663","url":null,"abstract":"This study investigates the distribution of pressure around a 5-mm-high backward-facing step model and counter-rotating vane vortex generators in a transonic wind tunnel by applying pressure-sensitive paint. Vortex generators with heights of 0.0, 0.2, 0.5, and 1.0 relative to the thickness of the turbulent boundary layer were used under transonic flow conditions at Mach numbers of 0.8 and 0.9. Oil flow visualization results were found to be similar to those of the pressure-sensitive paint measurements in terms of reattachment length and flow characteristics. This direct comparison not only confirms the reliability of PSP but also demonstrates its superior ability to visualize complex pressure distributions. Although the oil flow visualization technique effectively depicted the flow patterns, the pressure-sensitive paint approach provided more detailed information by depicting two-dimensional pressure distributions and identifying low-pressure regions around the vortex generators. Among all configurations, the vortex generator with h* = 0.5 was found to be the most effective in shortening the recirculation region and advancing the reattachment point under both Mach numbers.","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"109 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2025-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Planform-customized waverider design using flows with variable mach numbers","authors":"Xufei Meng,&nbsp;Peng Bai,&nbsp;Chuanzhen Liu","doi":"10.1016/j.ast.2025.110654","DOIUrl":"10.1016/j.ast.2025.110654","url":null,"abstract":"<div><div>The traditional waverider is usually designed in a single design state. Thus, the performance advantage of the high lift-to-drag ratio (L/D) is difficult to maintain when a waverider deviates from the design state, limiting its application in wide-speed aerodynamic design. In this paper, by employing the conical flows with different Mach numbers in different osculating planes, the planform-customized waverider design using variable-Mach-number flows is proposed based on the osculating-cone treatment. Then the double swept waveriders, which shared the same leading-edge profile, were generated with different spanwise distributions of Mach numbers. Computational Fluid Dynamics techniques were employed to analyze the aerodynamic forces, longitudinal stabilities, and shock wave structures of the waveriders. Compared with the conventional waveriders using fixed conical flows, the wide-speed performances of this planform-customized waverider were analyzed in hypersonic regime. Results showed that the planform-customized waverider design using variable-Mach-number flows is feasible, enlarging design space efficiently. Over a wide range of hypersonic velocities, the waverider using the flows with variable Mach numbers featured balanced L/D and volume efficiencies. When the planform shapes were identical, however, the difference in aerodynamic centers between the variable-Mach-number and fixed-Mach-number waveriders was significantly slight. The slight difference indicates that the variable-Mach-number flows as basis flows had mere effect on longitudinal stability. Meanwhile, compared with the fixed-Mach-number waveriders with equal volume and identical planform shape, the wide-speed L/D ratios of the variable-Mach-number waveriders were not superior in hypersonic regime.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"167 ","pages":"Article 110654"},"PeriodicalIF":5.0,"publicationDate":"2025-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural design and performance analysis of a novel helium heater for precooled air-breathing combined engines","authors":"Hongwei Mao, Hongmin Mao, Jiahui Yang, Xionghui Li, Fucheng Chang, Jinxin Liu, Xuefeng Chen, Minglong Du","doi":"10.1016/j.ast.2025.110657","DOIUrl":"https://doi.org/10.1016/j.ast.2025.110657","url":null,"abstract":"To address the issues of high weight and structural complexity of the helium heater in precooled combined engines, a novel design of combustion heat exchange integrated helium heater is put forward. A numerical model validated by experimental data is developed to predict its performance. The flow and heat transfer characteristics of the helium heater are analyzed in detail. The crucial influence of structural design parameters on helium heater performance is thoroughly revealed. And the variations of heater performance with deviations in working fluid parameters are explored. The conclusions can be made as follows: The proposed design integrates the combustion and heat exchange components, eliminating the need for complex gas delivery pipelines and active thermal protection systems, thereby reducing weight and complexity. The heat transfer coefficient increases as the helium is heated. The difference between the maximum and minimum values of the heat transfer coefficient can reach up to 1500 W/m²·K. The transverse pitch has a greater impact on the heat transfer and flow resistance performance than the longitudinal pitch, with an optimal transverse pitch (<ce:italic>S<ce:inf loc=\"post\">1</ce:inf>/d</ce:italic>) of 2.0. As the number of radial layers in the helium heater increases, the total heat transfer coefficient is accordingly enhanced, which in turn reduces the required number of axial layers. The reduction in axial layers has a greater impact than the increase in radial layers, resulting in a reduction in helium heater weight. Compared to the heat transfer coefficient, the total pressure recovery coefficient on the helium side is more sensitive to changes in helium flow rate. Considering the temperature tolerance of the walls, an excess air coefficient between 3.5 and 4 is recommended.","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"5 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic response analysis of the composite cylindrical cabin with vibration isolation system in supersonic airflow","authors":"Dong Shao, Bo Li, Weige Liang, Hongguang Wang, Ningze Sun","doi":"10.1016/j.ast.2025.110660","DOIUrl":"https://doi.org/10.1016/j.ast.2025.110660","url":null,"abstract":"This paper investigates the internal and external vibration transmission performance of the cylindrical cabin and plate with the vibration isolation system (CPIS) in the thermal aerodynamic environment. The theoretical model is established using the first order shear deformation theory (FSDT), and the center point virtual spring method (CVSM) is adopted to connect the base plate and the cylindrical cabin. The vibration isolation system is connected to the base plate based on the motion relationship. The aerodynamic environment is established by the piston theory, and the coupled structure is solved through Hamilton's variation principle and the Jacobi differential quadrature method (JDQM). The accuracy of this method is verified by comparing the cylindrical cabin flutter, as well as the frequencies, modes and dynamic responses of the coupled structure with the finite element method (FEM). Additionally, the spring and damping value of the vibration isolation system and the installation position are determined. The vibration isolation dynamic responses of the base plate coupling positions and plate thickness ratio to the forced vibration of the coupled structure are investigated under constant thermal conditions and different dimensionless aerodynamic pressures, in order to find the optimal parameter.","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"110 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665067","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Optimal Size of Square-Lobed Trailing Edges in Transonic Flow Over a Backward-Facing Step","authors":"Kai Zeng, Xiang Shen, Liming Yang, Laurent Dala","doi":"10.1016/j.ast.2025.110662","DOIUrl":"https://doi.org/10.1016/j.ast.2025.110662","url":null,"abstract":"Controlling flow separation and reattachment in transonic conditions over a backward‐facing step (BFS) is a critical challenge with significant implications for drag, noise, and structural stability. Square‐lobed trailing edges have emerged as a promising passive flow control strategy. In this study, we extend previous research by investigating an unprecedented range of lobe protrusion heights (LPH), from the traditional <ce:italic>0.4ℎ</ce:italic> up to <ce:italic>1.0ℎ</ce:italic>. To determine whether larger geometries offer additional performance benefits. Using a combination of Reynolds-Averaged Navier–Stokes (RANS) and Detached Eddy Simulation (DES) at a transonic Mach number of 0.8 and a Reynolds number of <ce:italic>1.8×105</ce:italic>, we analyse the influence of LPH on reattachment lengths and three-dimensional flow dynamics. For clarity, we differentiate between the “peak” region (upper edge) and the “valley” region (lower edge) of the step. The results indicate a significant reduction in the valley reattachment length as LPH increases, while the shortest reattachment length in the peak region occurs at LPH = <ce:italic>0.6ℎ</ce:italic>, with less pronounced differences at higher LPH values. DES reveals that larger LPH configurations enhance the stability and organisation of lateral vortices, reducing chaotic flow behaviours compared to the baseline BFS.","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"24 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing Unmanned aerial vehicle Aerodynamics: A Two-Stage Approach Using Genetic Algorithms and Adjoint Methods","authors":"Mohammad Javad Ebrahimi, Mahmoud Pasandidehfard, Ali Esmaeili, Mohammad Hossein Moghimi Esfandabadi","doi":"10.1016/j.ast.2025.110605","DOIUrl":"https://doi.org/10.1016/j.ast.2025.110605","url":null,"abstract":"In this article, we discuss the design of a flying wing using a default model and the application of the Taguchi test design method, genetic evolutionary optimization algorithm, and adjoint derivative optimization method, along with fluid dynamics calculations. Simulations were conducted using compressible Reynolds-averaged equations based on the Large Eddy Simulation (LES) turbulence model and the k-ω Shear Stress Transport (SST) model at a speed of 50 m/s and a Reynolds number of 1.6 million. The first stage of optimization was performed on the wing sections using the adjoint method. Subsequently, the second and third stages were optimized through a response surface method and genetic algorithm, involving 11 variables across these stages with a total of 50 tests conducted. The test case is a lambda-shaped flying wing named Saccon, which features wings with a 53-degree sweep angle. In this research, in order to optimize the lift coefficient and the ratio of lift to drag coefficients, a target function has been defined for the lift-to-drag ratio. By selecting this objective, both the lift and the lift-to-drag ratio can be increased. The results indicate that the impact of the variables varies for each section of the wing. Ultimately, the newly designed body achieved a 10% increase in aerodynamic efficiency compared to the default model through the use of optimization algorithms. Additionally, the drag coefficient increased by 140%, successfully completing the design process with multi-stage optimization techniques.","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"661 1","pages":""},"PeriodicalIF":5.6,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated optimization of de-spin actuator design and operating parameters for tail-controlled flight vehicle","authors":"Xinrui Luo,&nbsp;Meng Zhang,&nbsp;Zhihong Deng,&nbsp;Kai Shen,&nbsp;Yingxin Liu","doi":"10.1016/j.ast.2025.110625","DOIUrl":"10.1016/j.ast.2025.110625","url":null,"abstract":"<div><div>Achieving high-precision guidance for high-spinning flight vehicles necessitates effective de-spin actuator design that simultaneously preserves flight stability. This study presents an innovative integrated optimization framework for Tail-controlled Flight Vehicles (TFV) with a dual-spin structure. We first propose a novel de-spin actuator design for the Aft Control Kit (ACK) to facilitate a stable low-spin environment while maintaining the forebody's high-spin stability. Crucially, a Phy-sense Neural Network (PSNN) is introduced for high-fidelity aerodynamic coefficient prediction, demonstrating a significant 58% error reduction compared to conventional Conv1D models by integrating fundamental fluid dynamics principles. Furthermore, we develop a decoupled integrated optimization strategy based on quantitative sensitivity analysis. This strategy, combined with a seven-degree-of-freedom (7-DoF) ballistic model, systematically optimizes the de-spin fin's configuration and operating parameters. The comprehensive framework significantly improves both overall flight performance and de-spin effectiveness. Simulation and experimental results rigorously validate the proposed design's capabilities, offering valuable methodological insights for the advanced design and optimization of future high-spinning vehicles.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"167 ","pages":"Article 110625"},"PeriodicalIF":5.0,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel control of supersonic combustion instability via weakly coupled identical oscillators induced by multi-injector design","authors":"Yidan Chen,&nbsp;Tao Cui","doi":"10.1016/j.ast.2025.110653","DOIUrl":"10.1016/j.ast.2025.110653","url":null,"abstract":"<div><div>This study presents a passive control method for suppressing supersonic combustion instability by strategically modifying fuel injector arrangements. Experimental results show that conventional multi-injector configurations behave as weakly coupled identical oscillators, whose synchronization drives large-amplitude combustion oscillations. By implementing a staggered injector geometry to introduce controlled phase differences between oscillators, we achieve a 47.1 % reduction in pressure oscillation amplitude (from 40.1 % to 21.2 %) and a 53.6 % suppression of flame front oscillations (from 22.4 % to 10.4 %), while expanding the ignition boundary by 25 % (equivalence ratio reduced from 0.48 to 0.36). The control mechanism relies on periodic generation and migration of localized recirculation zones, establishing dynamically stable combustion regions. High-speed schlieren imaging and CH* chemiluminescence analysis confirm that the modified injector arrangement disrupts oscillator synchronization while improving fuel-air mixing. This approach provides combustion chamber designers with a new geometric degree of freedom for instability control, offering quantifiable performance benefits without requiring active systems. The findings, supported by coupled oscillator theory, are applicable to multi-injector propulsion systems including scramjets, gas turbines, and rocket engines.</div></div>","PeriodicalId":50955,"journal":{"name":"Aerospace Science and Technology","volume":"167 ","pages":"Article 110653"},"PeriodicalIF":5.0,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144665071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}