Pub Date : 2020-12-30DOI: 10.20998/2078-774x.2020.02.06
Y. A. Oleynik, S. A. Saprykin, S. Naumenko
An algorithm for calculating the flow rate of fuel natural gas in a gas pumping unit (GPU) (GPU drive) and for several identical gas pumping units operating together in compressor shop or compressor station. The flow calculation model takes into account thermal characteristics, operating modes and limitations of GPU parameters. Main task when determining consumption fuel gas is the calculation of the capacity of compressor shops and GPU. Power calculation takes into account compression ratio and flow rate of gas pumped by compressors. After calculation of GPA working capacity GPA drives efficiency factor is determined and fuel gas flow rate in GPU (GPU drive) is calculated. Exact values and limitations of thermal parameters (allowable pressures, temperatures, pumped gas flow rates, efficiency factors of compressors and drives). At the same time, the parameters of the GPU will depend on its operating mode of the GAP. The algorithm takes into account four limitations of GPU parameters: minimum flow rate of pumped gas in GPU compressor, minimum drive power of the GPU compressor, maximum gas temperature at the outlet of the GPA compressor, maximum gas compression ratio in the compressor. Without taking into account these restrictions, the calculation of fuel gas may be incorrect, since the impossible operation mode of the GPU will be taken into account. Developed algorithm takes into account all necessary characteristics and limitations of GPU parameters, simulates real robot modes of existing and designed GPU.
{"title":"Determination of Fuel Gas Flow Rate in Gas Pumping Unit With Gas Turbine Drive and Centrifugal Supercharger","authors":"Y. A. Oleynik, S. A. Saprykin, S. Naumenko","doi":"10.20998/2078-774x.2020.02.06","DOIUrl":"https://doi.org/10.20998/2078-774x.2020.02.06","url":null,"abstract":"An algorithm for calculating the flow rate of fuel natural gas in a gas pumping unit (GPU) (GPU drive) and for several identical gas pumping units operating together in compressor shop or compressor station. The flow calculation model takes into account thermal characteristics, operating modes and limitations of GPU parameters. Main task when determining consumption fuel gas is the calculation of the capacity of compressor shops and GPU. Power calculation takes into account compression ratio and flow rate of gas pumped by compressors. After calculation of GPA working capacity GPA drives efficiency factor is determined and fuel gas flow rate in GPU (GPU drive) is calculated. Exact values and limitations of thermal parameters (allowable pressures, temperatures, pumped gas flow rates, efficiency factors of compressors and drives). At the same time, the parameters of the GPU will depend on its operating mode of the GAP. The algorithm takes into account four limitations of GPU parameters: minimum flow rate of pumped gas in GPU compressor, minimum drive power of the GPU compressor, maximum gas temperature at the outlet of the GPA compressor, maximum gas compression ratio in the compressor. Without taking into account these restrictions, the calculation of fuel gas may be incorrect, since the impossible operation mode of the GPU will be taken into account. Developed algorithm takes into account all necessary characteristics and limitations of GPU parameters, simulates real robot modes of existing and designed GPU.","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129370902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-30DOI: 10.20998/2078-774x.2020.01.05
V. Demchenko, V. Konyk
The article is devoted to the analysis of non-productive losses in the generation of thermal energy. The causes of heat losses and their localization on the station equipment, technological pipeline and at unbalance of technological processes are established. As a result of the analysis, recommendations were given for the joint use of nuclear power plants (NPPs) or thermal power plants (TPPs) with available renewable energy sources (RES), using thermal storage systems, which will balance the system "generation - transportation - consumption". The use of stationary and mobile heat accumulators in the generation of RES, secondary thermal energy (TER) will reduce heat loss, use low-potential sources, which will relieve service equipment, reduce fuel consumption (FER) and harmful emissions into the environment. Also, it is recommended to conduct a full energy audit of station equipment and pipelines. Implement replacement of technically obsolete equipment with low efficiency, replace piping and insulation. Update the automation system, introduce a process scheduling system. Balance technological processes.
{"title":"Reducing of Non-Productive Heat Losses in Energy Generation","authors":"V. Demchenko, V. Konyk","doi":"10.20998/2078-774x.2020.01.05","DOIUrl":"https://doi.org/10.20998/2078-774x.2020.01.05","url":null,"abstract":"The article is devoted to the analysis of non-productive losses in the generation of thermal energy. The causes of heat losses and their localization on the station equipment, technological pipeline and at unbalance of technological processes are established. As a result of the analysis, recommendations were given for the joint use of nuclear power plants (NPPs) or thermal power plants (TPPs) with available renewable energy sources (RES), using thermal storage systems, which will balance the system \"generation - transportation - consumption\". The use of stationary and mobile heat accumulators in the generation of RES, secondary thermal energy (TER) will reduce heat loss, use low-potential sources, which will relieve service equipment, reduce fuel consumption (FER) and harmful emissions into the environment. Also, it is recommended to conduct a full energy audit of station equipment and pipelines. Implement replacement of technically obsolete equipment with low efficiency, replace piping and insulation. Update the automation system, introduce a process scheduling system. Balance technological processes.","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"213 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129429635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-12-30DOI: 10.20998/2078-774x.2020.02.05
V. Bezhan, Vladimir Zhitarenko
{"title":"Modeling and Analysis of Energy Efficiency Parameters of Medium Pressure Boilers Using a Mixture of Natural and Blast Furnace Gases Taking into Account Air Intakes","authors":"V. Bezhan, Vladimir Zhitarenko","doi":"10.20998/2078-774x.2020.02.05","DOIUrl":"https://doi.org/10.20998/2078-774x.2020.02.05","url":null,"abstract":"","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122265786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-03-09DOI: 10.20998/2078-774x.2019.02.01
O. Chernousenko, Oleksandr Pavlovich Usaty, Dmitro Victorovich Rindyuk, V. Peshko
{"title":"Establishing Control Over the Residual Resource of 200 MW Steam Turbines by Optimization of Percentage of Launches from Different Thermal States","authors":"O. Chernousenko, Oleksandr Pavlovich Usaty, Dmitro Victorovich Rindyuk, V. Peshko","doi":"10.20998/2078-774x.2019.02.01","DOIUrl":"https://doi.org/10.20998/2078-774x.2019.02.01","url":null,"abstract":"","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125086460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-28DOI: 10.20998/2078-774x.2019.03.10
M. Hryshyn, Borys P. Zaytsev, I. Palkov, Oleksandr H. Kantor, Yurii H. Paschenko
The development data of the welded combined average-pressure rotor for the steam turbine of a new generation К-325-23.5 produced by JSC “Turboatom” have been given. To develop it, we used the data given in experimental-&-engineering and research papers devoted to the selection of the rational forms of individual discs and the loci of circular cofferdams with welded seams to provide an acceptable level of stresses, which is one of the main requirements to be met when designing welded rotors. The mode of deformation of some options of a new rotor structure was defined using the method of finite elements and the software of IPMach of the National Academy of Sciences of Ukraine. In addition to the stresses that arise under the action of centrifugal forces and thermal stresses we took into account during our computations low bending alternating stresses caused by weight loads and these stresses are very dangerous due to their cyclic character. When combined with tensile stresses caused by centrifugal forces at the bottom run of welded seams, these can result in an increased amount of possible defects. The experimental-&-engineering research done by us allowed for the transformation of aggravating stresses caused by centrifugal forces at the bottom run of welded seams into compressive stresses. A special research was done to select the weld groove geometry, electrodes, the weld technology and thermal treatment modes after the welding to remove residual stresses. Welded specimens with the welded seams of a different configuration (type of weld groove geometry) and the specimens cut out of the welded seams of the end parts of full-scale model were subjected to fatigue tests. A high workability and unavailability of drawbacks that are peculiar for the rotors with capped discs individualize this type of rotor advantageously in comparison with the latter. Expensive balancing work requires the reduction of start operations by a factor of two. A combined “composite” rotor behaves in a more consistent manner with the spin up during the transition across critical rotation frequencies and at rated revolutions; a smoother operation is observed.
{"title":"Welded Combined Rotor for the Steam Turbine K-325-23.5","authors":"M. Hryshyn, Borys P. Zaytsev, I. Palkov, Oleksandr H. Kantor, Yurii H. Paschenko","doi":"10.20998/2078-774x.2019.03.10","DOIUrl":"https://doi.org/10.20998/2078-774x.2019.03.10","url":null,"abstract":"The development data of the welded combined average-pressure rotor for the steam turbine of a new generation К-325-23.5 produced by JSC “Turboatom” have been given. To develop it, we used the data given in experimental-&-engineering and research papers devoted to the selection of the rational forms of individual discs and the loci of circular cofferdams with welded seams to provide an acceptable level of stresses, which is one of the main requirements to be met when designing welded rotors. The mode of deformation of some options of a new rotor structure was defined using the method of finite elements and the software of IPMach of the National Academy of Sciences of Ukraine. In addition to the stresses that arise under the action of centrifugal forces and thermal stresses we took into account during our computations low bending alternating stresses caused by weight loads and these stresses are very dangerous due to their cyclic character. When combined with tensile stresses caused by centrifugal forces at the bottom run of welded seams, these can result in an increased amount of possible defects. The experimental-&-engineering research done by us allowed for the transformation of aggravating stresses caused by centrifugal forces at the bottom run of welded seams into compressive stresses. A special research was done to select the weld groove geometry, electrodes, the weld technology and thermal treatment modes after the welding to remove residual stresses. Welded specimens with the welded seams of a different configuration (type of weld groove geometry) and the specimens cut out of the welded seams of the end parts of full-scale model were subjected to fatigue tests. A high workability and unavailability of drawbacks that are peculiar for the rotors with capped discs individualize this type of rotor advantageously in comparison with the latter. Expensive balancing work requires the reduction of start operations by a factor of two. A combined “composite” rotor behaves in a more consistent manner with the spin up during the transition across critical rotation frequencies and at rated revolutions; a smoother operation is observed.","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122335967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-28DOI: 10.20998/2078-774x.2019.03.06
O. Tretiak, Anton Kovryga, M. Repetenko, R. Nurmetov
{"title":"The Research of the Thermal State of the Umbrella Type Hydrogenerator by САЕ Methods","authors":"O. Tretiak, Anton Kovryga, M. Repetenko, R. Nurmetov","doi":"10.20998/2078-774x.2019.03.06","DOIUrl":"https://doi.org/10.20998/2078-774x.2019.03.06","url":null,"abstract":"","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115827691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-27DOI: 10.20998/2078-774x.2018.13.10
Pavel Petrovich Gontarovskiy, N. Garmash
{"title":"Estimating the Loading of Nonlinear Element Connections in the Unit-Foundation-Base Turbine System at Seismic Activities","authors":"Pavel Petrovich Gontarovskiy, N. Garmash","doi":"10.20998/2078-774x.2018.13.10","DOIUrl":"https://doi.org/10.20998/2078-774x.2018.13.10","url":null,"abstract":"","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"86 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114939639","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-27DOI: 10.20998/2078-774x.2018.12.15
O. Tretiak
The analysis of existing designs of the stator fastening of Turbogenerators of various design versions is carried out. It is shown that the appli- cation of a spring suspension is the integral part of the design of Turbogenerators rated 100 MW and higher. The detailed calculation of the complex stressed state of the stators suspension of Turbogenerators manufactured at SE "PLANT "ELECTROTYAZHMASH" rated 200 MW and 250 MW with hydrogen and hydrogen-water cooling is submitted in the scientific work, taking into account the uneven thermal distribution along the horizontal axis of the aggregate for some number of electrical-sheet steels. The various types of the stator deformation caused by a number of forces are considered. It is proposed to carry out the calculation of mechanical stresses by iterative execution of mechanical and thermal calculations coordinated with electrical stresses. As limiting conditions for taking in to account of forces caused by temperature changes, the limiting conditions of the first kind were considered. At that, in the mechanical calculation, it is necessary to take into account the design peculiarities for each row of springs, taking into consideration the correction for temperature. The key factor is the difference between the calculated vibrations for a stand separately core and its installation in to the casing with suspension, depending up on the modulus of elasticity of the stacked up laminated core for electrical-sheet steels 3413, 3414 GOST21427.1-83, M270-50A. The possibil- ity of changing of steel 38Х2Н2ВА to steel 34CrNiMo6 and steel 40NiCrMo7 is shown, provided that the GOST8479-70 complies with the same strength group.
{"title":"Peculiarities of Designing of Suspensions for Stators of High Power Turbogenerators","authors":"O. Tretiak","doi":"10.20998/2078-774x.2018.12.15","DOIUrl":"https://doi.org/10.20998/2078-774x.2018.12.15","url":null,"abstract":"The analysis of existing designs of the stator fastening of Turbogenerators of various design versions is carried out. It is shown that the appli- cation of a spring suspension is the integral part of the design of Turbogenerators rated 100 MW and higher. The detailed calculation of the complex stressed state of the stators suspension of Turbogenerators manufactured at SE \"PLANT \"ELECTROTYAZHMASH\" rated 200 MW and 250 MW with hydrogen and hydrogen-water cooling is submitted in the scientific work, taking into account the uneven thermal distribution along the horizontal axis of the aggregate for some number of electrical-sheet steels. The various types of the stator deformation caused by a number of forces are considered. It is proposed to carry out the calculation of mechanical stresses by iterative execution of mechanical and thermal calculations coordinated with electrical stresses. As limiting conditions for taking in to account of forces caused by temperature changes, the limiting conditions of the first kind were considered. At that, in the mechanical calculation, it is necessary to take into account the design peculiarities for each row of springs, taking into consideration the correction for temperature. The key factor is the difference between the calculated vibrations for a stand separately core and its installation in to the casing with suspension, depending up on the modulus of elasticity of the stacked up laminated core for electrical-sheet steels 3413, 3414 GOST21427.1-83, M270-50A. The possibil- ity of changing of steel 38Х2Н2ВА to steel 34CrNiMo6 and steel 40NiCrMo7 is shown, provided that the GOST8479-70 complies with the same strength group.","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130457422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-27DOI: 10.20998/2078-774X.2018.12.16
A. Siryi, M. Abdulin
{"title":"Analyzing Power Indices for the Jet-Niche Fuel Combustion System","authors":"A. Siryi, M. Abdulin","doi":"10.20998/2078-774X.2018.12.16","DOIUrl":"https://doi.org/10.20998/2078-774X.2018.12.16","url":null,"abstract":"","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121162190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-27DOI: 10.20998/2078-774X.2018.13.15
D. A. Dolmatov, Masoud Hajivand
Numerical experiments was carried out to predict the total temperature characteristics and formation of nitrogen oxide emissions and pattern factor in an annular combustor liner based on geometrical parameters and location and rows of different air admission holes, for 6 various cases, using computational fluid dynamics (CFD) .The simulation has been performed using ANSYS CFX including finite rate chemistry and eddy dissipation model, for simulation of liquid kerosene (Jet A) – air combustion after fuel droplet evaporation. The spray modeling was performed, including Rosin-Rammler droplet distribution. Thermal and prompt nitrogen oxide (NO x ) formation was performed to predicting NO x emission characteristics with a k -e model of turbulent. In this investigation the 3D CAD model of the realistic annular combustion chamber is presented for the simulation with double radial air swirler for the better mixing fuel with air. Beside this the characteristic and the flame structure is presented including the contour plots of total temperature and NO concentration at the outlet of the combustor liner and in cross section plane along the X axis from the injector center of the combustor including the chart of the velocity and NO, CO, CO 2 , O 2 and the total temperature along the liner from the injector center. For the combustion of kerosene with air 2 step kinetic schemes are presented in this study. The results show that the best result with the low concentration of NO is the case 5 but with a high percentage of pressure drop and the case 3 have the maximum concentration of NO with the low percentage of pressure drop.
{"title":"On Low-Emission Annular Combustor Based on Designing of Liner Air Admission Holes","authors":"D. A. Dolmatov, Masoud Hajivand","doi":"10.20998/2078-774X.2018.13.15","DOIUrl":"https://doi.org/10.20998/2078-774X.2018.13.15","url":null,"abstract":"Numerical experiments was carried out to predict the total temperature characteristics and formation of nitrogen oxide emissions and pattern factor in an annular combustor liner based on geometrical parameters and location and rows of different air admission holes, for 6 various cases, using computational fluid dynamics (CFD) .The simulation has been performed using ANSYS CFX including finite rate chemistry and eddy dissipation model, for simulation of liquid kerosene (Jet A) – air combustion after fuel droplet evaporation. The spray modeling was performed, including Rosin-Rammler droplet distribution. Thermal and prompt nitrogen oxide (NO x ) formation was performed to predicting NO x emission characteristics with a k -e model of turbulent. In this investigation the 3D CAD model of the realistic annular combustion chamber is presented for the simulation with double radial air swirler for the better mixing fuel with air. Beside this the characteristic and the flame structure is presented including the contour plots of total temperature and NO concentration at the outlet of the combustor liner and in cross section plane along the X axis from the injector center of the combustor including the chart of the velocity and NO, CO, CO 2 , O 2 and the total temperature along the liner from the injector center. For the combustion of kerosene with air 2 step kinetic schemes are presented in this study. The results show that the best result with the low concentration of NO is the case 5 but with a high percentage of pressure drop and the case 3 have the maximum concentration of NO with the low percentage of pressure drop.","PeriodicalId":416126,"journal":{"name":"NTU \"KhPI\" Bulletin: Power and heat engineering processes and equipment","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128941804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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