{"title":"Design and analysis of bionic baffles for coupled thermal and dynamic performance enhancement in shell-and-tube heat exchangers","authors":"Wenpeng Shen , Xiangjiang Xu , Xiancheng Zhang , Peishuo Tang , Wei Song","doi":"10.1016/j.ijthermalsci.2026.110677","DOIUrl":"10.1016/j.ijthermalsci.2026.110677","url":null,"abstract":"<div><div>Shell-and-tube heat exchangers (STHXs) are widely used in industrial thermal systems; however, conventional baffle designs often suffer from high pressure drop, non-uniform shell-side flow distribution, and flow-induced vibration of tube bundles. To address these coupled thermo-hydraulic and dynamic limitations, two bio-inspired baffle configurations—a cobweb-shaped baffle (CWB) and a batwing-shaped baffle (BWB)—are proposed and numerically investigated in comparison with a conventional double-flower baffle (DFB). Three dimensional steady-state simulations are conducted by solving the incompressible continuity, momentum, and energy equations. Turbulence is modeled using the standard <em>k–ε</em> model with standard wall functions, and the near-wall mesh resolution is maintained within the recommended y<sup>+</sup> range. Water with temperature-dependent thermophysical properties is employed as the working fluid, while viscous dissipation and thermal radiation are neglected. Flow-induced vibration is evaluated using a one-way fluid-structure interaction (FSI) approach, assuming that tube displacements are sufficiently small to avoid feedback on the flow field. The numerical results indicate that both bio-inspired baffles enhance shell-side heat transfer by inducing geometry-controlled secondary flows and improving flow redistribution. The BWB-STHX achieves a 4.53 % increase in the convective heat transfer coefficient with only a 0.65 % increase in pressure drop, resulting in superior overall thermal-hydraulic performance relative to the DFB configuration. In contrast, the CWB-STHX generates distributed small-scale vortices that improve flow uniformity and reduce the maximum tube-bundle vibration displacement by 19.79 %, while maintaining stable thermal performance. Overall, the proposed bio-inspired baffle designs offer an effective trade-off between heat transfer enhancement, pressure-drop penalty, and vibration mitigation, providing practical guidance for high-performance STHX design.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110677"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145975205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nadja Accioly Espíndola , Wellington Pinheiro dos Santos , Rita de Cássia Fernandes de Lima
{"title":"Numerical analysis of the influence of thermophysical parameters on the surface temperature of breast substitute geometry obtained from infrared images","authors":"Nadja Accioly Espíndola , Wellington Pinheiro dos Santos , Rita de Cássia Fernandes de Lima","doi":"10.1016/j.ijthermalsci.2026.110673","DOIUrl":"10.1016/j.ijthermalsci.2026.110673","url":null,"abstract":"<div><div>The need of research in new methods for screening, diagnosis, classification, and treatment of breast cancer arose from the high incidence and mortality rates of this kind of cancer. The investigation presented in this article is based on the knowledge that at the beginning of the formation of a breast abnormality, there is an increase in the blood perfusion rate around the abnormality due to the creation of new blood vessels, in a process that is called neoangiogenesis. Consequently, there is an increase in the temperature caused by the augmented blood perfusion in the referred region, Thus, this article is a part of a study aimed to understand the relationship between the thermophysical parameters of breast and tumor tissues and, combined with other techniques including artificial intelligence, to prove that using infrared images can be an important auxiliary tool for detecting breast abnormalities. The interest on the thermophysical parameters of the breast is due to the uncertainties of accurate values available in the literature. In general, those values are not directly measured, they vary from person to person. Many of them were measured <em>in vitro</em> or in animal living tissues. Therefore, experiments designed to validate the aforementioned parameters are essential, particularly when employing numerical simulations, in order to obtain the most accurate values possible. This study analyzes the influence of eight parameters on numerical simulations of the surface temperature of a breast substitute geometry obtained from infrared (IR) images, ultrasound (US), and clinical examinations of two patients from the Hospital das Clínicas at the Federal University of Pernambuco (HC-UFPE), Pernambuco - Brazil. One of the patients had a malignant tumor, and the other had a benign tumor. The Design of Experiments (DOE) technique was employed to conduct the analyses, which required 256 numerical simulations. The actual breast geometry of each patient was reconstructed from the dimensions obtained through infrared (IR) imaging, complemented by a metallic grid positioned in front of the patient to ensure spatial calibration. Two studies were conducted for each patient. In the first study, the breast tumor was modeled according to the tumor dimensions identified during the patient's US examination. In the second, the dimensions of the breast tumor were artificially increased to verify the influence of tumor size on the breast temperatures. Therefore, we concluded that the thermophysical parameters of the tumor have less influence than the thermophysical parameters of the breast when calculating the temperature profiles under study. The thermal conductivity and blood perfusion of the breast were the parameters with the most significant influence on the surface temperature of the breast over the tumor region, for all patients observed.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110673"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Junhui Huang , Li Yi , Bo Wang , Jing Chen , Yanjie Wu
{"title":"Perforated Ag nanodisks for metal-assisted guided-mode terahertz thermal-absorption sensors in antibiotic biomedicine","authors":"Junhui Huang , Li Yi , Bo Wang , Jing Chen , Yanjie Wu","doi":"10.1016/j.ijthermalsci.2026.110710","DOIUrl":"10.1016/j.ijthermalsci.2026.110710","url":null,"abstract":"<div><div>This paper presents a two-dimensional grating composite structure of perforated Ag nanodisks for metal-assisted guided-mode resonance (GMR) sensors operating in the terahertz band. The structure is composed of a mixture of Ag, GaAs and SiO<sub>2</sub>, and takes advantage of the surface plasmon resonance (SPR) excited by the metal in the grating, which greatly enhances its sensing capability. We achieved strong thermal-absorption rates at 4.559 THz and 7.012 THz, reaching 99.79 % and 99.60 %, respectively. The manufacturing tolerances of the structure were evaluated to enhance the wide applicability of the sensing. It is worth noting that when the refractive index of the analyte varies within the range of 1.30–1.36, this structure demonstrates excellent sensing performance: The maximum sensitivity (S) reaches 3.4 THz/RIU, the full-width at half-maximum (FWHM) is 0.011 THz, and the maximum Q factor and figure of merit (FOM) reach 635.91 and 137.5 RIU<sup>−1</sup>, respectively. These advantageous features mean that the sensor structure we have proposed can provide more accurate measurement results in a specific environment, especially with outstanding application potential in fields such as biomedical sensing, semiconductor sensing, and material physics sensing.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110710"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Thermal-hydraulic analysis and multi objective optimization in double-layered wavy microchannel heat sinks with combining porous ribs","authors":"Ce Wang, Wei Chen","doi":"10.1016/j.ijthermalsci.2026.110697","DOIUrl":"10.1016/j.ijthermalsci.2026.110697","url":null,"abstract":"<div><div>To obtain better thermal-hydraulic behaviors in double-layered microchannel heat sinks in microelectronic devices with large power, the comparisons of thermal resistance and pump power are conducted among five types of double-layered microchannels respectively with wavy or straight upper and lower channels, as well as porous layer paved on the side solid ribs to form combining ribs in upper channel or not. The effects of the ratio of wave amplitude to wavelength (A/<em>λ</em>), width ratio of the porous layer to rib (<em>β</em>), porosity in porous layer of combining ribs (<em>ε</em>), and height ratio of the lower channel to the upper (<em>γ</em>) in double-layered wavy microchannel on heat transfer and flow are numerically analyzed. The figure of merit (<em>FOM</em>) is defined to evaluate the thermal-hydraulic performance in double-layered wavy microchannel. The porous layer on side wall decreases stay time of coolant with smaller or less flowing vortex in concave, and enlarges transverse convection between coolant and ribs, while the lower flowing resistance occurs in cases with the alike cross section along wavy channel in doubled-layer wavy channel. The higher <em>FOM</em> occurs in double-layered wavy microchannel with wavy top cover and bottom as well as porous layer paved on the side wall in upper channel, and lower straight lower channel, in which the better thermal-hydraulic performance occurs in cases of <em>A</em>/λ = 0.12, <em>ε</em> = 0.6, <em>β</em> = 0.6 and <em>γ</em> = 0.8. Besides, the 30.49 % decrease and 75.23 % increase respectively in thermal resistance and pump power in double-layered wavy channel with <em>γ</em> above 0.5 can be obtained for multi objective optimization based on NSGA-II and TOPSIS algorithms. All results can be taken into account for the utilization of double-layered wavy microchannel for cooling microelectronic devices with high heat flux densities.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110697"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effects of process parameters on the growth and deposition of silica particles during multi-burner CVD synthesis of large-size fused silica glass","authors":"Weifeng Deng , Wenjie Zhang , Yaosong Huang","doi":"10.1016/j.ijthermalsci.2026.110722","DOIUrl":"10.1016/j.ijthermalsci.2026.110722","url":null,"abstract":"<div><div>This paper investigates silica particles behavior during large-size fused silica glass synthesis by multi-burner CVD method using a comprehensive numerical model that couples turbulent flow, chemical reactions, and particle dynamics. We systematically analyze how three key process parameters—the height of the deposition surface, the number of burners, and the hydrogen/oxygen equivalence ratio— affect particle growth and deposition. The results show that the deposition height and burner count alter particle size, spatial distribution, and deposition uniformity by modifying the flow-field structure and the spatial distribution of heat release. The hydrogen/oxygen equivalence ratio controls particle nucleation and growth by altering the flame environment and vapor supersaturation. A deposition height of <em>H</em> = 0.6 m, a stoichiometric equivalence ratio (φ = 1.0), and four burners together produce the most uniform particle growth and the highest deposition efficiency. Under these conditions, heat and mass transport are balanced, which improves both the optical quality and the dimensional stability of the synthesized glass. This study offers quantitative guidance for scaling up production of high-performance fused silica glass with enhanced optical homogeneity.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110722"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146074395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aolong Liu, Xiaoyong Xie, Baoyi Hu, Zhaoliang Wang
{"title":"Transient non-equilibrium thermal transport in silicon-based FinFET","authors":"Aolong Liu, Xiaoyong Xie, Baoyi Hu, Zhaoliang Wang","doi":"10.1016/j.ijthermalsci.2026.110715","DOIUrl":"10.1016/j.ijthermalsci.2026.110715","url":null,"abstract":"<div><div>With the continuous scaling of transistor dimensions, localized high-temperature hotspots induced by self-heating effects have become a critical constraint on device reliability. Thermal dissipation has emerged as a key bottleneck limiting both performance improvement and further miniaturization of semiconductor devices. In particular, the transient thermal effects induced by periodic switching during normal device operation are of great importance, as the underlying non-equilibrium thermal transport processes significantly influence device performance. In this work, a coupled electron–phonon Monte Carlo simulation approach is employed to investigate silicon-based FinFETs, systematically revealing the formation mechanism of hotspots and the associated electron scattering processes. On this basis, the transient non-equilibrium thermal transport of phonons is simulated by solving the Boltzmann transport equation (BTE) using the phonon Monte Carlo (MC) method, with the hotspot profile obtained from Electron-MC simulations serving as the heat source term. By comparing the heat source duration with the phonon transit time across the hotspot region, the transient thermal transport characteristics of phonon non-equilibrium states across different time scales are analyzed. Furthermore, simulations performed at typical wireless communication transistor switching frequencies examine the evolution of temperature, energy, and heat flux during dynamic operation, providing further insight into transient non-equilibrium effects in the device. This study offers valuable references for improving the accuracy of transistor thermal modeling and provides a theoretical foundation for the thermal management design of advanced-node devices.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110715"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146023867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Defect depth estimation using through-transmission pulsed thermography: A numerical and experimental investigation","authors":"Zain Ali, Sri Addepalli, Yifan Zhao","doi":"10.1016/j.ijthermalsci.2026.110723","DOIUrl":"10.1016/j.ijthermalsci.2026.110723","url":null,"abstract":"<div><div>Through-transmission pulsed thermography is widely recognised for offering higher defect resolution than reflection mode, yet its development has been hindered by challenges such as quantifying defect depth. This study addresses the depth quantification gap by introducing a novel depth estimation technique based on the relationship between defect depth and the Fourier number. The method is validated through both finite element modelling and laboratory experiments using calibration samples with embedded air-gap defects at known depths. Results show that depth estimation accuracy improves as defects approach the backwall, consistently across both simulation and experimental environments. Finite element analysis also demonstrates that the proposed technique outperforms the log second derivative method typically used in reflection mode. These findings advance the capability of through-transmission thermography for precise subsurface defect characterisation.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110723"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146074474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xin Wang , Kuan Su , Ming Zhu , Wenchao Han , Lin Liang , Liang Cheng , Yanan Liu , Yaohua Chen , Dongliang Cui , Shuping Chen
{"title":"Thermal management for cryogenic liquid storage systems: insulation control strategy using actively cooled thermal shields","authors":"Xin Wang , Kuan Su , Ming Zhu , Wenchao Han , Lin Liang , Liang Cheng , Yanan Liu , Yaohua Chen , Dongliang Cui , Shuping Chen","doi":"10.1016/j.ijthermalsci.2026.110664","DOIUrl":"10.1016/j.ijthermalsci.2026.110664","url":null,"abstract":"<div><div>The storage and transportation of large-scale liquid hydrogen (LH<sub>2</sub>) and liquid helium (LHe) face challenges such as evaporation losses and safety risks. This study proposes a thermal management strategy that combines an actively cooled thermal shield (ACTS) with multilayer insulation (MLI), employing a cold source medium to drive the ACTS in the temperature range of 77–87 K, establishing efficient thermal interception nodes. This approach overcomes the dependence of vapor-cooled shields (VCS) insulation on cold vapor medium and the energy efficiency limitations of active refrigeration technologies. An experimental platform was established to evaluate the insulation performance of ACTS, investigating the synergistic effects of ACTS temperature and MLI layer number on the insulation performance of the LHe tank. The temperature distribution patterns of ACTS and MLI were analyzed, along with the transient evaporation characteristics of cryogenic liquids. This study elucidates the active control strategy of ACTS in regulating insulation performance and assesses its economic benefits. The results indicate that the axial temperature difference of ACTS is strictly controlled within 0.5 K, effectively reshaping the MLI temperature field and significantly reducing the outermost radiation shield temperature, thereby suppressing radiative heat flux. In the LN<sub>2</sub> temperature range, the optimal MLI layer count is 30, while in the LAr temperature range, this can be extended to 40 layers. The minimum heat flux of T-MLI is 0.0643 W/m<sup>2</sup> (Case#5), representing a reduction of 87.8 %. The apparent thermal conductivity of T-MLI in the LHe temperature range is as low as 8.18 × 10<sup>−6</sup> W/(m·K) (Case#2). In the application of a 40 m<sup>3</sup> tank container, the average daily evaporation cost is reduced from $39,729 to $8,292, with the additional cost of the cold source medium being negligible. This results in significant return on investment and promising engineering applications. The experimental results validate the feasibility and economic viability of the ACTS insulation strategy, providing both theoretical and practical support for the safe storage and transportation of LH<sub>2</sub> and LHe.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110664"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145923773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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 simplified null-point method for high resolution contact temperature measurement by means of micro-thermocouples in vacuum conditions","authors":"L. Thiery, J.Y. Rauch, S. Euphrasie, B. Cretin","doi":"10.1016/j.ijthermalsci.2026.110667","DOIUrl":"10.1016/j.ijthermalsci.2026.110667","url":null,"abstract":"<div><div>We report on the possibility to measure the temperature of micro-devices by means of a micro-thermocouple in active mode with a simplified procedure of null-point method. Contrary to other reported procedures, there is no need of multiple scans at different distances to the sample surface. A single out of contact power calibration is required prior to the contact-point measurements. For them, only two successive measurements at different Joule heating powers of the thermocouple are necessary to deduce the actual surface temperature. We only used a low frequency voltage generator and high precision voltmeters without specific electronics except a low-pass RC filter. The reliability of the method is demonstrated with a platinum wire as a calibration tool.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110667"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145908880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luka S. Volkov , Yakov V. Miroshnikov , Aleksandr A. Firsov
{"title":"Modeling of jet mixing with supersonic crossflow under the influence of repeated spark discharges","authors":"Luka S. Volkov , Yakov V. Miroshnikov , Aleksandr A. Firsov","doi":"10.1016/j.ijthermalsci.2026.110680","DOIUrl":"10.1016/j.ijthermalsci.2026.110680","url":null,"abstract":"<div><div>Rapid mixing of fuel and oxidizer is one of the key conditions for raising the efficiency of combustion chambers with incoming supersonic flow. In this paper, the impact of spark discharges on mixing performance was studied. The mixing was considered for a standard flow configuration: a jet interacting with supersonic crossflow (JISC). The discussed method of mixing enhancement implied placing a repetitive spark discharge near the wall on the windward side of the jet in order to generate disturbances in the jet boundary. To identify the optimal operation modes of the discharge, several series of computer simulations of JISC were performed using the method of unsteady Reynolds-averaged Navier–Stokes equations (URANS). The periodic spark discharge was modeled as a pulsed volumetric heat source. The heat source had several operation modes with different energies and different pulse frequencies, having a fixed average power that was identical for all modes. For each mode, an integral criterion of mixing efficiency was calculated. It was found that the mixing efficiency depends on the discharge frequency non-monotonically. Optimal frequencies were found at which the mixing efficiency reached its maximum. An explanation for the discovered dependence was proposed based on the qualitative analysis of the flow characteristics. The mechanism of JISC instability was described in detail based on the baroclinic term in the vorticity equation for both natural and discharge-induced instabilities.</div></div>","PeriodicalId":341,"journal":{"name":"International Journal of Thermal Sciences","volume":"224 ","pages":"Article 110680"},"PeriodicalIF":5.0,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145975204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}