The Experts below are selected from a list of 120 Experts worldwide ranked by ideXlab platform
A. Pourmovahed - One of the best experts on this subject based on the ideXlab platform.
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Modeling of a Hydraulic Energy Regeneration System: Part II—Experimental Program
Journal of Dynamic Systems Measurement and Control-transactions of The Asme, 1992Co-Authors: A. Pourmovahed, N. H. Beachley, F. J. FronczakAbstract:This study reports experimental data taken with a Hydraulic energy regeneration system and compares the measured data with analytical results. The system tested consisted of two foam-filled Hydraulic Accumulators, a variable-displacement piston-type pump/motor, a reservoir and a flywheel. During a series of experiments, energy was repeatedly transferred between the Hydraulic Accumulators and the flywheel through the pump/motor. Computed system variables compared favorably with the experimental results. At high and moderate pump/motor swivel angles, the round-trip efficiency varied from 61 to 89 percent. It was significantly lower at small angles.
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durability testing of an elastomeric foam for use in Hydraulic Accumulators
Journal of Solar Energy Engineering-transactions of The Asme, 1990Co-Authors: A. PourmovahedAbstract:Etude experimentale sur banc d'essai de l'influence de l'âge d'un caoutchouc mousse de polyester-urethane injecte du cote gaz d'un accumulateur hydraulique, de son exposition a long terme a de l'azote gazeux a haute pression et de la frequence des cycles sur l'efficacite de l'accumulateur. Cette etude permet aussi de detecter les problemes de fonctionnement dus au caoutchouc mousse.
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An Experimental Thermal Time-Constant Correlation for Hydraulic Accumulators
Journal of Dynamic Systems Measurement and Control-transactions of The Asme, 1990Co-Authors: A. Pourmovahed, D. R. OtisAbstract:A thermal time-constant correlation based on experimental data is presented for gascharged Hydraulic Accumulators. This correlation, along with the thermal timeconstant model, permits accurate prediction of accumulator thermodynamic losses and the gas pressure and temperature history during compression or expansion. The gas is treated as a real gas, and all properties are allowed to vary with both pressure and temperature. The correlation was developed from heat transfer data obtained with a 2.5 liter piston-type accumulator charged with nitrogen gas. Both horizontal and vertical orientations were studied. The experiments covered the range, 2.6x10s
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an experimental thermal time constant correlation for Hydraulic Accumulators
Journal of Dynamic Systems Measurement and Control-transactions of The Asme, 1990Co-Authors: A. Pourmovahed, D. R. OtisAbstract:A thermal time-constant correlation based on experimental data is presented for gascharged Hydraulic Accumulators. This correlation, along with the thermal timeconstant model, permits accurate prediction of accumulator thermodynamic losses and the gas pressure and temperature history during compression or expansion. The gas is treated as a real gas, and all properties are allowed to vary with both pressure and temperature. The correlation was developed from heat transfer data obtained with a 2.5 liter piston-type accumulator charged with nitrogen gas. Both horizontal and vertical orientations were studied. The experiments covered the range, 2.6x10s
D. R. Otis - One of the best experts on this subject based on the ideXlab platform.
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An Experimental Thermal Time-Constant Correlation for Hydraulic Accumulators
Journal of Dynamic Systems Measurement and Control-transactions of The Asme, 1990Co-Authors: A. Pourmovahed, D. R. OtisAbstract:A thermal time-constant correlation based on experimental data is presented for gascharged Hydraulic Accumulators. This correlation, along with the thermal timeconstant model, permits accurate prediction of accumulator thermodynamic losses and the gas pressure and temperature history during compression or expansion. The gas is treated as a real gas, and all properties are allowed to vary with both pressure and temperature. The correlation was developed from heat transfer data obtained with a 2.5 liter piston-type accumulator charged with nitrogen gas. Both horizontal and vertical orientations were studied. The experiments covered the range, 2.6x10s
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an experimental thermal time constant correlation for Hydraulic Accumulators
Journal of Dynamic Systems Measurement and Control-transactions of The Asme, 1990Co-Authors: A. Pourmovahed, D. R. OtisAbstract:A thermal time-constant correlation based on experimental data is presented for gascharged Hydraulic Accumulators. This correlation, along with the thermal timeconstant model, permits accurate prediction of accumulator thermodynamic losses and the gas pressure and temperature history during compression or expansion. The gas is treated as a real gas, and all properties are allowed to vary with both pressure and temperature. The correlation was developed from heat transfer data obtained with a 2.5 liter piston-type accumulator charged with nitrogen gas. Both horizontal and vertical orientations were studied. The experiments covered the range, 2.6x10s
Jose Garciabravo - One of the best experts on this subject based on the ideXlab platform.
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energy efficiency comparison of Hydraulic Accumulators and ultracapacitors
Energies, 2020Co-Authors: Jorge Leonquiroga, Brittany Newell, Mahesh Krishnamurthy, Andres Gonzalezmancera, Jose GarciabravoAbstract:Energy regeneration systems are a key factor for improving energy efficiency in electroHydraulic machinery. This paper is focused on the study of electric energy storage systems (EESS) and Hydraulic energy storage systems (HESS) for energy regeneration applications. Two test benches were designed and implemented to compare the performance of the systems under similar operating conditions. The electrical system was configured with a set of ultracapacitors, and the Hydraulic system used a Hydraulic accumulator. Both systems were designed to have the same energy storage capacity. Charge and discharge cycle experiments were performed for the two systems in order to compare their power density, energy density, cost, and efficiency. According to the experimentally obtained results, the power density in the Hydraulic accumulator was 21.7% higher when compared with the ultracapacitors. Moreover, the cost/power ($/Watt) ratio in the Hydraulic accumulator was 2.9 times smaller than a set of ultracapacitors of the same energy storage capacity. On the other hand, the energy density in the set of ultracapacitors was 9.4 times higher, and the cost/energy ($/kWh) ratio was 2.9 times smaller when compared with the Hydraulic accumulator. Under the tested conditions, the estimated overall energy efficiency for the Hydraulic accumulator was 87.7%, and the overall energy efficiency for the ultracapacitor was 78.7%.
Jorge Leonquiroga - One of the best experts on this subject based on the ideXlab platform.
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energy efficiency comparison of Hydraulic Accumulators and ultracapacitors
Energies, 2020Co-Authors: Jorge Leonquiroga, Brittany Newell, Mahesh Krishnamurthy, Andres Gonzalezmancera, Jose GarciabravoAbstract:Energy regeneration systems are a key factor for improving energy efficiency in electroHydraulic machinery. This paper is focused on the study of electric energy storage systems (EESS) and Hydraulic energy storage systems (HESS) for energy regeneration applications. Two test benches were designed and implemented to compare the performance of the systems under similar operating conditions. The electrical system was configured with a set of ultracapacitors, and the Hydraulic system used a Hydraulic accumulator. Both systems were designed to have the same energy storage capacity. Charge and discharge cycle experiments were performed for the two systems in order to compare their power density, energy density, cost, and efficiency. According to the experimentally obtained results, the power density in the Hydraulic accumulator was 21.7% higher when compared with the ultracapacitors. Moreover, the cost/power ($/Watt) ratio in the Hydraulic accumulator was 2.9 times smaller than a set of ultracapacitors of the same energy storage capacity. On the other hand, the energy density in the set of ultracapacitors was 9.4 times higher, and the cost/energy ($/kWh) ratio was 2.9 times smaller when compared with the Hydraulic accumulator. Under the tested conditions, the estimated overall energy efficiency for the Hydraulic accumulator was 87.7%, and the overall energy efficiency for the ultracapacitor was 78.7%.
Mahesh Krishnamurthy - One of the best experts on this subject based on the ideXlab platform.
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energy efficiency comparison of Hydraulic Accumulators and ultracapacitors
Energies, 2020Co-Authors: Jorge Leonquiroga, Brittany Newell, Mahesh Krishnamurthy, Andres Gonzalezmancera, Jose GarciabravoAbstract:Energy regeneration systems are a key factor for improving energy efficiency in electroHydraulic machinery. This paper is focused on the study of electric energy storage systems (EESS) and Hydraulic energy storage systems (HESS) for energy regeneration applications. Two test benches were designed and implemented to compare the performance of the systems under similar operating conditions. The electrical system was configured with a set of ultracapacitors, and the Hydraulic system used a Hydraulic accumulator. Both systems were designed to have the same energy storage capacity. Charge and discharge cycle experiments were performed for the two systems in order to compare their power density, energy density, cost, and efficiency. According to the experimentally obtained results, the power density in the Hydraulic accumulator was 21.7% higher when compared with the ultracapacitors. Moreover, the cost/power ($/Watt) ratio in the Hydraulic accumulator was 2.9 times smaller than a set of ultracapacitors of the same energy storage capacity. On the other hand, the energy density in the set of ultracapacitors was 9.4 times higher, and the cost/energy ($/kWh) ratio was 2.9 times smaller when compared with the Hydraulic accumulator. Under the tested conditions, the estimated overall energy efficiency for the Hydraulic accumulator was 87.7%, and the overall energy efficiency for the ultracapacitor was 78.7%.
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Evaluation and selection of accumulator size in electric-Hydraulic hybrid (EH2) powertrain
2016 IEEE Transportation Electrification Conference and Expo (ITEC), 2016Co-Authors: Fei Shang, Mahesh Krishnamurthy, Jose M GarciaAbstract:An electric-Hydraulic hybrid (EH2) powertrain has shown significant potential in extending driving range and reducing battery discharge current stress. Research has shown that the size of the Hydraulic accumulator can have substantial influence on the performance and even the design of components in the overall electrified powertrain of the vehicle. This paper evaluates three sizes of Hydraulic accumulator for urban delivery trucks according to different degrees of hybridization in the electric Hydraulic hybrid powertrain. It has been shown that different Hydraulic Accumulators have notable impact on the reduction of battery current stress and electricity consumption, optimal utilization of Hydraulic energy storage system, weight, cost, and Hydraulic component efficiency.
