The Experts below are selected from a list of 213 Experts worldwide ranked by ideXlab platform
Ji Xiang Wang - One of the best experts on this subject based on the ideXlab platform.
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A hybrid cooling system combining self-adaptive single-phase mechanically Pumped Fluid loop and gravity-immune two-phase spray module
Energy Conversion and Management, 2018Co-Authors: Ji Xiang Wang, Yi Zhang, Mao Yufeng, Xian-wen NingAbstract:Abstract Although single-phase mechanically Pumped Fluid loop (MPFL) and two-phase spray cooling technologies have been investigated independently for decades, there is a lack of understanding on the combined operation of these two modules. The MPFL has been extensively utilized in the space thermal control system due to its technological maturity and gravity immunity. The spray cooling, which is characterized by the speciality in thermally dealing with the high heat flux equipment, has not gone that far owing to its complexity in the management of the two-phase flow in the space environment. It is also acknowledged that the MPFL, as an overall cooling strategy in the space thermal control system, will not be replaced completely in the foreseeable future because the primary on-board electronic devices require normal heat dissipation demand and only a few equipment such as on-board laser diode and multi-chip modules demand extreme high heat removal technologies. Therefore, a combination of the MPFL and spray cooling technologies, which constitutes the biggest innovation in this paper, is imperatively needed. A hybrid cooling system (HCS) combining the single-phase self-adaptive MPFL and gravity-immune two-phase spray module which satisfies various cooling demands is proposed in the present study. A validating system as a prototype was established on the basis of the optimal design method. Three test cases were conducted to verify the coordinated operation between the single-phase module and two-phase one and investigate thermal performances of both modules. In all the experiments, the controlled temperature of the cold plate in the MPFL remains within a range between 35.9 °C and 41.9 °C under the heat load from 50 W to 150 W. The highest heat flux acquired by the spray cooling module can be up to 468.8 W/cm2 with the superheat level being 70.0 °C. Results can be drawn that the two modules can be operated simultaneously and independently. Systematic operation efficiency of the proposed HCS is calculated to be 17.7 which displays a high economy of the proposed system.
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A self-driven temperature and flow rate co-adjustment mechanism based on Shape-Memory-Alloy (SMA) assembly for an adaptive thermal control coldplate module with on-orbit service characteristics
Applied Thermal Engineering, 2017Co-Authors: Wei Guo, Ji Xiang Wang, Sheng-nan Wang, Ming-liang Zhong, Jia-xun ZhangAbstract:Abstract An adaptive thermal control coldplate module (TCCM) was proposed in this paper to fulfill the requirements of modular thermal control systems for spacecrafts on-orbit services. The TCCM could provide flow rate and temperature co-adjustment by using Shape-Memory-Alloy (SMA) assembly which possesses self-driven abilities. In this paper, the adaptive thermal management mechanism of the TCCM integrated with a single phase mechanically Pumped Fluid loop (SPMPFL) is described in detail, a verification testbed was established to examine the TCCM dynamic characteristics. Various working conditions such as inlet temperature, flow rate and thermal load disturbances were imposed on the TCCM to inspect its startup and transient performance. It was observed that the TCCM may present robust temperature control results with low overshoot (maximum 16.8%) and small temperature control error (minimum 0.18%), fast time response (minimum 600 s) was also revealed. The results demonstrated that the well-designed TCCM provided effective autonomous flow-rate and temperature co-adjustment operations, which may be a promising candidate for realizing modular level adaptive thermal management for spacecrafts on-orbit services.
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A highly self-adaptive cold plate for the single-phase mechanically Pumped Fluid loop for spacecraft thermal management
Energy Conversion and Management, 2016Co-Authors: Ji Xiang Wang, Yun Ze Li, Yi Hao Liang, Sheng-nan Wang, Hong-sheng Zhang, Wei Guo, Shao Ping TianAbstract:Aiming to improve the conventional single-phase mechanically Pumped Fluid loop applied in spacecraft thermal control system, a novel actively-Pumped loop using distributed thermal control strategy was proposed. The flow control system for each branch consists primarily of a thermal control valve integrated with a paraffin-based actuator residing in the front part of each corresponding cold plate, where both coolant's flow rate and the cold plate's heat removal capability are well controlled sensitively according to the heat loaded upon the cold plate due to a conversion between thermal and mechanical energies. The operating economy enhances remarkably owing to no energy consumption in flow control process. Additionally, realizing the integration of the sensor, controller and actuator systems, it simplifies structure of the traditional mechanically Pumped Fluid loop as well. Revolving this novel scheme, mathematical model regarding design process of the highly specialized cold plate was entrenched theoretically. A validating system as a prototype was established on the basis of the design method and the scheduled objective of the controlled temperature (43°C). Then temperature control performances of the highly self-adaptive cold plate under various operating conditions were tested experimentally. During almost all experiments, the controlled temperature remains within a range of ±2°C around the set-point. Conclusions can be drawn that this self-driven control system is stable with sufficient fast transient responses and sufficient small steady-state errors.
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An integrated hardware-in-the-loop verification approach for dual heat sink systems of aerospace single phase mechanically Pumped Fluid loop
Applied Thermal Engineering, 2016Co-Authors: Wei Guo, Sheng-nan Wang, Ming-liang Zhong, Ji Xiang WangAbstract:Abstract Radiator-sublimator cooperative dual heat sink system (DHSS) has become the vanguard of the solutions of providing heat dissipation for on-board equipments exhausted heat augments in current and future aerospace missions. However, experimental investigation of a DHSS requires expensive cryovacuum environmental instruments with slow dynamic response in traditional methods, which is not suitable for fast real-time verifications. To overcome these limitations, this paper proposed a hardware-in-the-loop (HITL) based simulation approach for a DHSS integrated with single Fluid mechanically Pumped Fluid loop (SFMPFL) for aerospace applications. A verification system was established in which the DHSS is equivalently simulated by a valve-controlled cooling loop while the SFMPFL is physically represented. Additionally, via designed control strategies, heat dissipating and mode switch behaviors of the DHSS could be simulated. Aiming at inspecting steady and transient thermal control performance of the DHSS experimentally, various volumetric flow rates and heat inputs (up to 1600 W) were imposed on the SFMPFL. Results show that the system provided DHSS heat dissipation and temperature control simulations with high accuracy (within maximum error 5%) and acceptable time responses, proving that the proposed approach is capable of offering credible alternatives for ground-based DHSS evaluations in a more efficient and economical way.
Pradeep Bhandari - One of the best experts on this subject based on the ideXlab platform.
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performance of the mechanically Pumped Fluid loop rover heat rejection system used for thermal control of the mars science laboratory curiosity rover on the surface of mars
43rd International Conference on Environmental Systems, 2013Co-Authors: Pradeep Bhandari, Jennifer Miller, Gajanana C. Birur, David Bame, A. J. Mastropietro, Paul Karlmann, Kevin R AndersonAbstract:The challenging range of landing sites for which the Mars Science Laboratory Rover was designed, required a rover thermal management system that is capable of keeping temperatures controlled across a wide variety of environmental conditions. On the Martian surface where temperatures can be as cold as -123C and as warm as 38C, the Rover relies upon a Mechanically Pumped Fluid Loop (MPFL) Rover Heat Rejection System (RHRS) and external radiators to maintain the temperature of sensitive electronics and science instruments within a -40C to +50C range. The RHRS harnesses some of the waste heat generated from the Rover power source, known as the Multi Mission Radioisotope Thermoelectric Generator (MMRTG), for use as survival heat for the rover during cold conditions. The MMRTG produces 110 Watts of electrical power while generating waste heat equivalent to approximately 2000 Watts. Heat exchanger plates (hot plates) positioned close to the MMRTG pick up this survival heat from it by radiative heat transfer and supply it to the rover. This design is the first instance of use of a RHRS for thermal control of a rover or lander on the surface of a planet. After an extremely successful landing on Mars (August 5), the rover and the RHRS have performed flawlessly for close to an earth year (half the nominal mission life). This paper will share the performance of the RHRS on the Martian surface as well as compare it to its predictions.
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Leak mitigation in mechanically Pumped Fluid loops for long duration space missions
43rd International Conference on Environmental Systems, 2013Co-Authors: Jennifer Miller, Gajanana C. Birur, David Bame, A. J. Mastropietro, Pradeep Bhandari, Darlene Lee, Paul Karlmann, Yuanming LiuAbstract:Mechanically Pumped Fluid loops (MPFLs) are increasingly considered for spacecraft thermal control. A concern for long duration space missions is the leak of Fluid leading to performance degradation or potential loop failure. An understanding of leak rate through analysis, as well as destructive and non-destructive testing, provides a verifiable means to quantify leak rates. The system can be appropriately designed to maintain safe operating pressures and temperatures throughout the mission. Two MPFLs on the Mars Science Laboratory Spacecraft, launched November 26, 2011, maintain the temperature of sensitive electronics and science instruments within a -40°C to 50°C range during launch, cruise, and Mars surface operations. With over 100 meters of complex tubing, fittings, joints, flex lines, and pumps, the system must maintain a minimum pressure through all phases of the mission to provide appropriate performance. This paper describes the process of design, qualification, test, verification, and validation of the components and assemblies employed to minimize risks associated with excessive Fluid leaks from Pumped Fluid loop systems.
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design of accumulators and liquid gas charging of single phase mechanically Pumped Fluid loop heat rejection systems
42nd International Conference on Environmental Systems, 2012Co-Authors: Pradeep Bhandari, Gajanana C. Birur, David Bame, Paul Karlmann, Brenda Dudik, A. J. MastropietroAbstract:For single phase mechanically Pumped Fluid loops used for thermal control of spacecraft, a gas charged accumulator is typically used to modulate pressures within the loop. This is needed to accommodate changes in the working Fluid volume due to changes in the operating temperatures as the spacecraft encounters varying thermal environments during its mission. Overall, the three key requirements on the accumulator to maintain an appropriate pressure range throughout the mission are: accommodation of the volume change of the Fluid due to temperature changes, avoidance of pump cavitation and prevention of boiling in the liquid. The sizing and design of such an accumulator requires very careful and accurate accounting of temperature distribution within each element of the working Fluid for the entire range of conditions expected, accurate knowledge of volume of each Fluid element, assessment of corresponding pressures needed to avoid boiling in the liquid, as well as the pressures needed to avoid cavitation in the pump. The appropriate liquid and accumulator strokes required to accommodate the liquid volume change, as well as the appropriate gas volumes, require proper sizing to ensure that the correct pressure range is maintained during the mission. Additionally, a very careful assessment of the process for charging both the gas side and the liquid side of the accumulator is required to properly position the bellows and pressurize the system to a level commensurate with requirements. To achieve the accurate sizing of the accumulator and the charging of the system, sophisticated EXCEL based spreadsheets were developed to rapidly come up with an accumulator design and the corresponding charging parameters. These spreadsheets have proven to be computationally fast and accurate tools for this purpose. This paper will describe the entire process of designing and charging the system, using a case study of the Mars Science Laboratory (MSL) Fluid loops, which is en route to Mars for an August 2012 landing.
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Design of Accumulators and Liquid/Gas Charging of Single Phase Mechanically Pumped Fluid Loop Heat Rejection Systems
42nd International Conference on Environmental Systems, 2012Co-Authors: Pradeep Bhandari, Gajanana C. Birur, David Bame, Paul Karlmann, Brenda Dudik, A. J. MastropietroAbstract:For single phase mechanically Pumped Fluid loops used for thermal control of spacecraft, a gas charged accumulator is typically used to modulate pressures within the loop. This is needed to accommodate changes in the working Fluid volume due to changes in the operating temperatures as the spacecraft encounters varying thermal environments during its mission. Overall, the three key requirements on the accumulator to maintain an appropriate pressure range throughout the mission are: accommodation of the volume change of the Fluid due to temperature changes, avoidance of pump cavitation and prevention of boiling in the liquid. The sizing and design of such an accumulator requires very careful and accurate accounting of temperature distribution within each element of the working Fluid for the entire range of conditions expected, accurate knowledge of volume of each Fluid element, assessment of corresponding pressures needed to avoid boiling in the liquid, as well as the pressures needed to avoid cavitation in the pump. The appropriate liquid and accumulator strokes required to accommodate the liquid volume change, as well as the appropriate gas volumes, require proper sizing to ensure that the correct pressure range is maintained during the mission. Additionally, a very careful assessment of the process for charging both the gas side and the liquid side of the accumulator is required to properly position the bellows and pressurize the system to a level commensurate with requirements. To achieve the accurate sizing of the accumulator and the charging of the system, sophisticated EXCEL based spreadsheets were developed to rapidly come up with an accumulator design and the corresponding charging parameters. These spreadsheets have proven to be computationally fast and accurate tools for this purpose. This paper will describe the entire process of designing and charging the system, using a case study of the Mars Science Laboratory (MSL) Fluid loops, which is en route to Mars for an August 2012 landing.
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Mechanically Pumped Fluid Loop (MPFL) Technologies for Thermal Control of Future Mars Rovers
SAE Technical Paper Series, 2006Co-Authors: Gajanana C. Birur, David Bame, Pradeep Bhandari, M. Prina, Andre Yavrouian, Gary PlettAbstract:Mechanically Pumped Fluid loop has been the basis of thermal control architecture for the last two Mars lander and rover missions and is the key part of the MSL thermal architecture. Several MPFL technologies are being developed for the MSL rover include long-life pumps, thermal control valves, mechanical fittings for use with CFC-11 at elevated temperatures of approx.100 C. Over three years of life tests and chemical compatibility tests on these MPFL components show that MPFL technology is mature for use on MSL. The advances in MPFL technologies for MSL Rover will benefit any future MPFL applications on NASA s Moon, Mars and Beyond Program.
Gajanana C. Birur - One of the best experts on this subject based on the ideXlab platform.
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performance of the mechanically Pumped Fluid loop rover heat rejection system used for thermal control of the mars science laboratory curiosity rover on the surface of mars
43rd International Conference on Environmental Systems, 2013Co-Authors: Pradeep Bhandari, Jennifer Miller, Gajanana C. Birur, David Bame, A. J. Mastropietro, Paul Karlmann, Kevin R AndersonAbstract:The challenging range of landing sites for which the Mars Science Laboratory Rover was designed, required a rover thermal management system that is capable of keeping temperatures controlled across a wide variety of environmental conditions. On the Martian surface where temperatures can be as cold as -123C and as warm as 38C, the Rover relies upon a Mechanically Pumped Fluid Loop (MPFL) Rover Heat Rejection System (RHRS) and external radiators to maintain the temperature of sensitive electronics and science instruments within a -40C to +50C range. The RHRS harnesses some of the waste heat generated from the Rover power source, known as the Multi Mission Radioisotope Thermoelectric Generator (MMRTG), for use as survival heat for the rover during cold conditions. The MMRTG produces 110 Watts of electrical power while generating waste heat equivalent to approximately 2000 Watts. Heat exchanger plates (hot plates) positioned close to the MMRTG pick up this survival heat from it by radiative heat transfer and supply it to the rover. This design is the first instance of use of a RHRS for thermal control of a rover or lander on the surface of a planet. After an extremely successful landing on Mars (August 5), the rover and the RHRS have performed flawlessly for close to an earth year (half the nominal mission life). This paper will share the performance of the RHRS on the Martian surface as well as compare it to its predictions.
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Leak mitigation in mechanically Pumped Fluid loops for long duration space missions
43rd International Conference on Environmental Systems, 2013Co-Authors: Jennifer Miller, Gajanana C. Birur, David Bame, A. J. Mastropietro, Pradeep Bhandari, Darlene Lee, Paul Karlmann, Yuanming LiuAbstract:Mechanically Pumped Fluid loops (MPFLs) are increasingly considered for spacecraft thermal control. A concern for long duration space missions is the leak of Fluid leading to performance degradation or potential loop failure. An understanding of leak rate through analysis, as well as destructive and non-destructive testing, provides a verifiable means to quantify leak rates. The system can be appropriately designed to maintain safe operating pressures and temperatures throughout the mission. Two MPFLs on the Mars Science Laboratory Spacecraft, launched November 26, 2011, maintain the temperature of sensitive electronics and science instruments within a -40°C to 50°C range during launch, cruise, and Mars surface operations. With over 100 meters of complex tubing, fittings, joints, flex lines, and pumps, the system must maintain a minimum pressure through all phases of the mission to provide appropriate performance. This paper describes the process of design, qualification, test, verification, and validation of the components and assemblies employed to minimize risks associated with excessive Fluid leaks from Pumped Fluid loop systems.
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design of accumulators and liquid gas charging of single phase mechanically Pumped Fluid loop heat rejection systems
42nd International Conference on Environmental Systems, 2012Co-Authors: Pradeep Bhandari, Gajanana C. Birur, David Bame, Paul Karlmann, Brenda Dudik, A. J. MastropietroAbstract:For single phase mechanically Pumped Fluid loops used for thermal control of spacecraft, a gas charged accumulator is typically used to modulate pressures within the loop. This is needed to accommodate changes in the working Fluid volume due to changes in the operating temperatures as the spacecraft encounters varying thermal environments during its mission. Overall, the three key requirements on the accumulator to maintain an appropriate pressure range throughout the mission are: accommodation of the volume change of the Fluid due to temperature changes, avoidance of pump cavitation and prevention of boiling in the liquid. The sizing and design of such an accumulator requires very careful and accurate accounting of temperature distribution within each element of the working Fluid for the entire range of conditions expected, accurate knowledge of volume of each Fluid element, assessment of corresponding pressures needed to avoid boiling in the liquid, as well as the pressures needed to avoid cavitation in the pump. The appropriate liquid and accumulator strokes required to accommodate the liquid volume change, as well as the appropriate gas volumes, require proper sizing to ensure that the correct pressure range is maintained during the mission. Additionally, a very careful assessment of the process for charging both the gas side and the liquid side of the accumulator is required to properly position the bellows and pressurize the system to a level commensurate with requirements. To achieve the accurate sizing of the accumulator and the charging of the system, sophisticated EXCEL based spreadsheets were developed to rapidly come up with an accumulator design and the corresponding charging parameters. These spreadsheets have proven to be computationally fast and accurate tools for this purpose. This paper will describe the entire process of designing and charging the system, using a case study of the Mars Science Laboratory (MSL) Fluid loops, which is en route to Mars for an August 2012 landing.
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Design of Accumulators and Liquid/Gas Charging of Single Phase Mechanically Pumped Fluid Loop Heat Rejection Systems
42nd International Conference on Environmental Systems, 2012Co-Authors: Pradeep Bhandari, Gajanana C. Birur, David Bame, Paul Karlmann, Brenda Dudik, A. J. MastropietroAbstract:For single phase mechanically Pumped Fluid loops used for thermal control of spacecraft, a gas charged accumulator is typically used to modulate pressures within the loop. This is needed to accommodate changes in the working Fluid volume due to changes in the operating temperatures as the spacecraft encounters varying thermal environments during its mission. Overall, the three key requirements on the accumulator to maintain an appropriate pressure range throughout the mission are: accommodation of the volume change of the Fluid due to temperature changes, avoidance of pump cavitation and prevention of boiling in the liquid. The sizing and design of such an accumulator requires very careful and accurate accounting of temperature distribution within each element of the working Fluid for the entire range of conditions expected, accurate knowledge of volume of each Fluid element, assessment of corresponding pressures needed to avoid boiling in the liquid, as well as the pressures needed to avoid cavitation in the pump. The appropriate liquid and accumulator strokes required to accommodate the liquid volume change, as well as the appropriate gas volumes, require proper sizing to ensure that the correct pressure range is maintained during the mission. Additionally, a very careful assessment of the process for charging both the gas side and the liquid side of the accumulator is required to properly position the bellows and pressurize the system to a level commensurate with requirements. To achieve the accurate sizing of the accumulator and the charging of the system, sophisticated EXCEL based spreadsheets were developed to rapidly come up with an accumulator design and the corresponding charging parameters. These spreadsheets have proven to be computationally fast and accurate tools for this purpose. This paper will describe the entire process of designing and charging the system, using a case study of the Mars Science Laboratory (MSL) Fluid loops, which is en route to Mars for an August 2012 landing.
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Mechanically Pumped Fluid Loop (MPFL) Technologies for Thermal Control of Future Mars Rovers
SAE Technical Paper Series, 2006Co-Authors: Gajanana C. Birur, David Bame, Pradeep Bhandari, M. Prina, Andre Yavrouian, Gary PlettAbstract:Mechanically Pumped Fluid loop has been the basis of thermal control architecture for the last two Mars lander and rover missions and is the key part of the MSL thermal architecture. Several MPFL technologies are being developed for the MSL rover include long-life pumps, thermal control valves, mechanical fittings for use with CFC-11 at elevated temperatures of approx.100 C. Over three years of life tests and chemical compatibility tests on these MPFL components show that MPFL technology is mature for use on MSL. The advances in MPFL technologies for MSL Rover will benefit any future MPFL applications on NASA s Moon, Mars and Beyond Program.
A. J. Mastropietro - One of the best experts on this subject based on the ideXlab platform.
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performance of the mechanically Pumped Fluid loop rover heat rejection system used for thermal control of the mars science laboratory curiosity rover on the surface of mars
43rd International Conference on Environmental Systems, 2013Co-Authors: Pradeep Bhandari, Jennifer Miller, Gajanana C. Birur, David Bame, A. J. Mastropietro, Paul Karlmann, Kevin R AndersonAbstract:The challenging range of landing sites for which the Mars Science Laboratory Rover was designed, required a rover thermal management system that is capable of keeping temperatures controlled across a wide variety of environmental conditions. On the Martian surface where temperatures can be as cold as -123C and as warm as 38C, the Rover relies upon a Mechanically Pumped Fluid Loop (MPFL) Rover Heat Rejection System (RHRS) and external radiators to maintain the temperature of sensitive electronics and science instruments within a -40C to +50C range. The RHRS harnesses some of the waste heat generated from the Rover power source, known as the Multi Mission Radioisotope Thermoelectric Generator (MMRTG), for use as survival heat for the rover during cold conditions. The MMRTG produces 110 Watts of electrical power while generating waste heat equivalent to approximately 2000 Watts. Heat exchanger plates (hot plates) positioned close to the MMRTG pick up this survival heat from it by radiative heat transfer and supply it to the rover. This design is the first instance of use of a RHRS for thermal control of a rover or lander on the surface of a planet. After an extremely successful landing on Mars (August 5), the rover and the RHRS have performed flawlessly for close to an earth year (half the nominal mission life). This paper will share the performance of the RHRS on the Martian surface as well as compare it to its predictions.
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Leak mitigation in mechanically Pumped Fluid loops for long duration space missions
43rd International Conference on Environmental Systems, 2013Co-Authors: Jennifer Miller, Gajanana C. Birur, David Bame, A. J. Mastropietro, Pradeep Bhandari, Darlene Lee, Paul Karlmann, Yuanming LiuAbstract:Mechanically Pumped Fluid loops (MPFLs) are increasingly considered for spacecraft thermal control. A concern for long duration space missions is the leak of Fluid leading to performance degradation or potential loop failure. An understanding of leak rate through analysis, as well as destructive and non-destructive testing, provides a verifiable means to quantify leak rates. The system can be appropriately designed to maintain safe operating pressures and temperatures throughout the mission. Two MPFLs on the Mars Science Laboratory Spacecraft, launched November 26, 2011, maintain the temperature of sensitive electronics and science instruments within a -40°C to 50°C range during launch, cruise, and Mars surface operations. With over 100 meters of complex tubing, fittings, joints, flex lines, and pumps, the system must maintain a minimum pressure through all phases of the mission to provide appropriate performance. This paper describes the process of design, qualification, test, verification, and validation of the components and assemblies employed to minimize risks associated with excessive Fluid leaks from Pumped Fluid loop systems.
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design of accumulators and liquid gas charging of single phase mechanically Pumped Fluid loop heat rejection systems
42nd International Conference on Environmental Systems, 2012Co-Authors: Pradeep Bhandari, Gajanana C. Birur, David Bame, Paul Karlmann, Brenda Dudik, A. J. MastropietroAbstract:For single phase mechanically Pumped Fluid loops used for thermal control of spacecraft, a gas charged accumulator is typically used to modulate pressures within the loop. This is needed to accommodate changes in the working Fluid volume due to changes in the operating temperatures as the spacecraft encounters varying thermal environments during its mission. Overall, the three key requirements on the accumulator to maintain an appropriate pressure range throughout the mission are: accommodation of the volume change of the Fluid due to temperature changes, avoidance of pump cavitation and prevention of boiling in the liquid. The sizing and design of such an accumulator requires very careful and accurate accounting of temperature distribution within each element of the working Fluid for the entire range of conditions expected, accurate knowledge of volume of each Fluid element, assessment of corresponding pressures needed to avoid boiling in the liquid, as well as the pressures needed to avoid cavitation in the pump. The appropriate liquid and accumulator strokes required to accommodate the liquid volume change, as well as the appropriate gas volumes, require proper sizing to ensure that the correct pressure range is maintained during the mission. Additionally, a very careful assessment of the process for charging both the gas side and the liquid side of the accumulator is required to properly position the bellows and pressurize the system to a level commensurate with requirements. To achieve the accurate sizing of the accumulator and the charging of the system, sophisticated EXCEL based spreadsheets were developed to rapidly come up with an accumulator design and the corresponding charging parameters. These spreadsheets have proven to be computationally fast and accurate tools for this purpose. This paper will describe the entire process of designing and charging the system, using a case study of the Mars Science Laboratory (MSL) Fluid loops, which is en route to Mars for an August 2012 landing.
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Design of Accumulators and Liquid/Gas Charging of Single Phase Mechanically Pumped Fluid Loop Heat Rejection Systems
42nd International Conference on Environmental Systems, 2012Co-Authors: Pradeep Bhandari, Gajanana C. Birur, David Bame, Paul Karlmann, Brenda Dudik, A. J. MastropietroAbstract:For single phase mechanically Pumped Fluid loops used for thermal control of spacecraft, a gas charged accumulator is typically used to modulate pressures within the loop. This is needed to accommodate changes in the working Fluid volume due to changes in the operating temperatures as the spacecraft encounters varying thermal environments during its mission. Overall, the three key requirements on the accumulator to maintain an appropriate pressure range throughout the mission are: accommodation of the volume change of the Fluid due to temperature changes, avoidance of pump cavitation and prevention of boiling in the liquid. The sizing and design of such an accumulator requires very careful and accurate accounting of temperature distribution within each element of the working Fluid for the entire range of conditions expected, accurate knowledge of volume of each Fluid element, assessment of corresponding pressures needed to avoid boiling in the liquid, as well as the pressures needed to avoid cavitation in the pump. The appropriate liquid and accumulator strokes required to accommodate the liquid volume change, as well as the appropriate gas volumes, require proper sizing to ensure that the correct pressure range is maintained during the mission. Additionally, a very careful assessment of the process for charging both the gas side and the liquid side of the accumulator is required to properly position the bellows and pressurize the system to a level commensurate with requirements. To achieve the accurate sizing of the accumulator and the charging of the system, sophisticated EXCEL based spreadsheets were developed to rapidly come up with an accumulator design and the corresponding charging parameters. These spreadsheets have proven to be computationally fast and accurate tools for this purpose. This paper will describe the entire process of designing and charging the system, using a case study of the Mars Science Laboratory (MSL) Fluid loops, which is en route to Mars for an August 2012 landing.
Wei Guo - One of the best experts on this subject based on the ideXlab platform.
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A self-driven temperature and flow rate co-adjustment mechanism based on Shape-Memory-Alloy (SMA) assembly for an adaptive thermal control coldplate module with on-orbit service characteristics
Applied Thermal Engineering, 2017Co-Authors: Wei Guo, Ji Xiang Wang, Sheng-nan Wang, Ming-liang Zhong, Jia-xun ZhangAbstract:Abstract An adaptive thermal control coldplate module (TCCM) was proposed in this paper to fulfill the requirements of modular thermal control systems for spacecrafts on-orbit services. The TCCM could provide flow rate and temperature co-adjustment by using Shape-Memory-Alloy (SMA) assembly which possesses self-driven abilities. In this paper, the adaptive thermal management mechanism of the TCCM integrated with a single phase mechanically Pumped Fluid loop (SPMPFL) is described in detail, a verification testbed was established to examine the TCCM dynamic characteristics. Various working conditions such as inlet temperature, flow rate and thermal load disturbances were imposed on the TCCM to inspect its startup and transient performance. It was observed that the TCCM may present robust temperature control results with low overshoot (maximum 16.8%) and small temperature control error (minimum 0.18%), fast time response (minimum 600 s) was also revealed. The results demonstrated that the well-designed TCCM provided effective autonomous flow-rate and temperature co-adjustment operations, which may be a promising candidate for realizing modular level adaptive thermal management for spacecrafts on-orbit services.
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A highly self-adaptive cold plate for the single-phase mechanically Pumped Fluid loop for spacecraft thermal management
Energy Conversion and Management, 2016Co-Authors: Ji Xiang Wang, Yun Ze Li, Yi Hao Liang, Sheng-nan Wang, Hong-sheng Zhang, Wei Guo, Shao Ping TianAbstract:Aiming to improve the conventional single-phase mechanically Pumped Fluid loop applied in spacecraft thermal control system, a novel actively-Pumped loop using distributed thermal control strategy was proposed. The flow control system for each branch consists primarily of a thermal control valve integrated with a paraffin-based actuator residing in the front part of each corresponding cold plate, where both coolant's flow rate and the cold plate's heat removal capability are well controlled sensitively according to the heat loaded upon the cold plate due to a conversion between thermal and mechanical energies. The operating economy enhances remarkably owing to no energy consumption in flow control process. Additionally, realizing the integration of the sensor, controller and actuator systems, it simplifies structure of the traditional mechanically Pumped Fluid loop as well. Revolving this novel scheme, mathematical model regarding design process of the highly specialized cold plate was entrenched theoretically. A validating system as a prototype was established on the basis of the design method and the scheduled objective of the controlled temperature (43°C). Then temperature control performances of the highly self-adaptive cold plate under various operating conditions were tested experimentally. During almost all experiments, the controlled temperature remains within a range of ±2°C around the set-point. Conclusions can be drawn that this self-driven control system is stable with sufficient fast transient responses and sufficient small steady-state errors.
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An integrated hardware-in-the-loop verification approach for dual heat sink systems of aerospace single phase mechanically Pumped Fluid loop
Applied Thermal Engineering, 2016Co-Authors: Wei Guo, Sheng-nan Wang, Ming-liang Zhong, Ji Xiang WangAbstract:Abstract Radiator-sublimator cooperative dual heat sink system (DHSS) has become the vanguard of the solutions of providing heat dissipation for on-board equipments exhausted heat augments in current and future aerospace missions. However, experimental investigation of a DHSS requires expensive cryovacuum environmental instruments with slow dynamic response in traditional methods, which is not suitable for fast real-time verifications. To overcome these limitations, this paper proposed a hardware-in-the-loop (HITL) based simulation approach for a DHSS integrated with single Fluid mechanically Pumped Fluid loop (SFMPFL) for aerospace applications. A verification system was established in which the DHSS is equivalently simulated by a valve-controlled cooling loop while the SFMPFL is physically represented. Additionally, via designed control strategies, heat dissipating and mode switch behaviors of the DHSS could be simulated. Aiming at inspecting steady and transient thermal control performance of the DHSS experimentally, various volumetric flow rates and heat inputs (up to 1600 W) were imposed on the SFMPFL. Results show that the system provided DHSS heat dissipation and temperature control simulations with high accuracy (within maximum error 5%) and acceptable time responses, proving that the proposed approach is capable of offering credible alternatives for ground-based DHSS evaluations in a more efficient and economical way.
