Dynamic Simulation of a Large Scale Pulsed Load Helium Refrigerator

Briend, P.; Deschildre, C.; Icart, Y.; Sequeira, SA; Weisend, J. G.

doi:10.1063/1.3422322

Cited by 15 publications

(6 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Out of different expander based cold ends, considering the trade-off between reliability and performance efficiency, EXP+JT configuration is a reasonable compromise that avoids the use of somewhat less reliable 'wet expander'. From the results obtained, it may be concluded that Config.4-1 with cold end as EXP+JT may be considered as a more acceptable configuration and many large-scale plants seen around the world today [18][19][20][21][22] have similar configurations as shown in Fig. 5. …”

Section: Trade-offs In Cold End Designmentioning

confidence: 99%

See 1 more Smart Citation

Exergy analysis of large-scale helium liquefiers: Evaluating design trade-offs

Thomas¹,

Ghosh²,

Chowdhury³

2014

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract. It is known that higher heat exchanger area, more number of expanders with higher efficiency and more involved configuration with multi-pressure compression system increase the plant efficiency of a helium liquefier. However, they involve higher capital investment and larger size. Using simulation software Aspen Hysys v 7.0 and exergy analysis as the tool of analysis, authors have attempted to identify various trade-offs while selecting the number of stages, the pressure levels in compressor, the cold-end configuration, the heat exchanger surface area, the maximum allowable pressure drop in heat exchangers, the efficiency of expanders, the parallel/series connection of expanders etc. Use of more efficient cold ends reduces the number of refrigeration stages and the size of the plant. For achieving reliability along with performance, a configuration with a combination of expander and Joule-Thomson valve is found to be a better choice for cold end. Use of multi-pressure system is relevant only when the number of refrigeration stages is more than 5. Arrangement of expanders in series reduces the number of expanders as well as the heat exchanger size with slight expense of plant efficiency. Superior heat exchanger (having less pressure drop per unit heat transfer area) results in only 5% increase of plant performance even when it has 100% higher heat exchanger surface area.

show abstract

Section: Trade-offs In Cold End Designmentioning

confidence: 99%

“…Therefore, many helium plants in operation today have configurations as those shown in Fig. 6 [19][20][21][22].…”

Section: Trade-offs In Expander Arrangementsmentioning

confidence: 99%

Exergy analysis of large-scale helium liquefiers: Evaluating design trade-offs

Thomas¹,

Ghosh²,

Chowdhury³

2014

AIP Conference Proceedings

View full text Add to dashboard Cite

show abstract

“…Therefore, it is necessary to develop a control scheme to smooth the pulse heat load. Some methods have been proposed to mitigate the effects of pulsed heat load from fusion devices [4][5]. Rohan Dutta proposed a novel technique using a supercritical storage Dewar to mitigate the pulse heat load [6], however, this proposal was based on a numerical model and was not yet validated by the experimental operation.…”

Section: Control Schemementioning

confidence: 99%

Analysis of the cryogenic system behavior for pulsed heat load in EAST

Hu¹,

Zhuang²,

Zhou³

et al. 2014

AIP Conference Proceedings

View full text Add to dashboard Cite

Abstract. EAST is the first full superconducting fusion device. The plasma is confined by the magnetic fields generated from a large set of superconducting magnets which are made of cable in-conduit conductor (CICC). In operation, these magnets suffer heat loads from thermal and nuclear radiation from the surrounding components and plasma as well as the eddy currents and the AC losses generated within the magnets, together with the heat conduction through supports and the resistive heat generated at the current lead transiting to room temperature. The cryogenic system of our EAST consists of a 2kW/4K helium refrigerator and a distribution system for the cooling of poloidal field (PF) and toroidal field (TF) coils, structures, thermal shields, buslines and current leads. Pulsed heat load is the main difference between the cryogenic system of a full superconducting Tokamak system and other large scale cryogenic systems. The cryogenic system operates in a pulsed heat loads mode requiring the helium refrigerator to remove periodically large heat loads in time. At the same time, the cryogenic system parameters such as helium cooling superconducting magnets, helium refrigerator and helium distribution system are changing. In this paper, the variation range of the parameters of superconducting magnets and refrigerator has been analyzed in the typical plasma discharge mode. The control scheme for the pulsed loads characteristics of the cryogenic system has been proposed, the implementation of which helps to smooth the pulse loads and to improve the stability of the operation of the cryogenic system.

show abstract

“…Bradu B et al developed a dynamic simulator, PROCOS (PROcess and COntrol Simulator), to improve knowledge on the cryogenic system for LHC [2] . Deschildre C et al simulated the 800 W@4.5 K helium refrigerator at CEA [5] , and applied it to the refrigerator design to cope with the pulsed heat load [6] .…”

Section: Introductionmentioning

confidence: 99%

Process Modeling and Dynamic Simulation for EAST Helium Refrigerator

Lu¹,

Peng²,

Ming³

et al. 2016

Plasma Sci. Technol.

View full text Add to dashboard Cite

In this paper, the process modeling and dynamic simulation for the EAST helium refrigerator has been completed. The cryogenic process model is described and the main components are customized in detail. The process model is controlled by the PLC simulator, and the realtime communication between the process model and the controllers is achieved by a customized interface. Validation of the process model has been confirmed based on EAST experimental data during the cool down process of 300-80 K. Simulation results indicate that this process simulator is able to reproduce dynamic behaviors of the EAST helium refrigerator very well for the operation of long pulsed plasma discharge. The cryogenic process simulator based on control architecture is available for operation optimization and control design of EAST cryogenic systems to cope with the long pulsed heat loads in the future.

show abstract

Dynamic Simulation of a Large Scale Pulsed Load Helium Refrigerator

Cited by 15 publications

References 2 publications

Exergy analysis of large-scale helium liquefiers: Evaluating design trade-offs

Exergy analysis of large-scale helium liquefiers: Evaluating design trade-offs

Analysis of the cryogenic system behavior for pulsed heat load in EAST

Process Modeling and Dynamic Simulation for EAST Helium Refrigerator

Contact Info

Product

Resources

About