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You searched for subject:(Pulse Tube Cooler). Showing records 1 – 2 of 2 total matches.

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Indian Institute of Science

1. Kumar, Kranthi J R A. Studies on Single and Two Stage Stirling Type Pulse Tube Coolers of Low and Medium Capacities including Performance Enhancement of Pressure Wave GeneratoI and a Novel Helium Recondensation System.

Degree: PhD, Engineering, 2019, Indian Institute of Science

Cryocoolers are mechanical devices that produce cold at temperatures below -150 °C. Work required to produce the cold is supplied by a Pressure Wave Generator (PWG). This thesis is concerned with the development and analysis of Stirling type pulse tube cooler (PTC) systems of low and medium capacities along with performance improvement of PWG and design of a novel oil free and low maintenance helium recondensation system based on Stirling type pulse tube coolers and Joule-Thomson expansion. Pressure Wave Generator is a crucial part of pulse tube cooler system. Performance of PWG depends on many parameters like the seal gap, piston diameter etc. E ects of these parameters have been studied in detail. Analysis was done to arrive at optimal values and a methodology is suggested to improve performance. The analysis was applied extensively to indigenously developed Pressure Wave Generator (PWG-1). A signi cant improvement, reduced mechanical losses and lowered input electric current, has been found by application of the suggested methodology. The development of pulse tube coolers of low and medium capacities was studied. In low capacity coolers, the available PV power is low; thus, requiring an ultra e cient design. In medium capacity coolers, the available PV power can pose problems like acoustic matching, streaming etc. A low capacity pulse tube cryocooler capable of 0.5 W at 80 K and acoustically matched to indigenous Pressure Wave Generator PWG-1 was designed, fabricated and tested. Inertance tube con guration which plays signi cant role in low input power coolers has been analyzed. A no load temperature of 74 K was achieved with input power of 59 W; corresponding to a cooling power of 0.22 W at 80 K. The amplitude of mass ow passing into the pulse tube cooler has been measured by using a hot wire anemometer calibrated in oscillatory ow condition. A medium capacity pulse tube cryocooler capable of 10 W at 80 K was designed and developed. It requires an estimated input PV power of 375 W. On the other hand, the only available large PWG for this work, PWG-2, has a rated PV power output of 900 W at the rated piston stroke, thus posing the problem of acoustic matching. Improvement of acoustic matching between the PTC and PWG was studied by varying lling pressure, inertance tube con guration, and by using a long transfer line. A no load temperature of 72 K corresponding to 1 W at 80 K was achieved. It is concluded that steps to improve acoustic matching are useful only to a limited extent and acoustic matching has to be ensured at the design stage itself. A medium capacity two stage pulse tube cooler capable of reaching 25 K is described. Analytical proof has been given to shown that a two stage pulse tube cooler is thermo-dynamically less e cient than a single stage pulse tube cooler. But a two stage PTC is required to reduce regenerator losses. A no load temperature of 40.4 K was achieved at 24.1 bar lling pressure with an input power of 750 W. The e ects of pulse tube volume and regenerator con… Advisors/Committee Members: Jacob, Subhash (advisor).

Subjects/Keywords: Pulse Tube Cooler; Hybrid Cryocoolers; Pressure Wave Generator (PWG); PTC; Helium Recondensation System; Pulse Tube Cryocooler; Pulse Tube Refrigerator; PWG-1; Instrumentation and Applied Physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Kumar, K. J. R. A. (2019). Studies on Single and Two Stage Stirling Type Pulse Tube Coolers of Low and Medium Capacities including Performance Enhancement of Pressure Wave GeneratoI and a Novel Helium Recondensation System. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/4224

Chicago Manual of Style (16th Edition):

Kumar, Kranthi J R A. “Studies on Single and Two Stage Stirling Type Pulse Tube Coolers of Low and Medium Capacities including Performance Enhancement of Pressure Wave GeneratoI and a Novel Helium Recondensation System.” 2019. Doctoral Dissertation, Indian Institute of Science. Accessed October 25, 2020. http://etd.iisc.ac.in/handle/2005/4224.

MLA Handbook (7th Edition):

Kumar, Kranthi J R A. “Studies on Single and Two Stage Stirling Type Pulse Tube Coolers of Low and Medium Capacities including Performance Enhancement of Pressure Wave GeneratoI and a Novel Helium Recondensation System.” 2019. Web. 25 Oct 2020.

Vancouver:

Kumar KJRA. Studies on Single and Two Stage Stirling Type Pulse Tube Coolers of Low and Medium Capacities including Performance Enhancement of Pressure Wave GeneratoI and a Novel Helium Recondensation System. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2019. [cited 2020 Oct 25]. Available from: http://etd.iisc.ac.in/handle/2005/4224.

Council of Science Editors:

Kumar KJRA. Studies on Single and Two Stage Stirling Type Pulse Tube Coolers of Low and Medium Capacities including Performance Enhancement of Pressure Wave GeneratoI and a Novel Helium Recondensation System. [Doctoral Dissertation]. Indian Institute of Science; 2019. Available from: http://etd.iisc.ac.in/handle/2005/4224


Indian Institute of Science

2. Gour, Abhay Singh. Design And Development of Linear Moving Magnet Synchronous Motor Based Twin PTC And HTS Level Sensor for LOX Recondenser.

Degree: PhD, Faculty of Engineering, 2017, Indian Institute of Science

Cryocoolers are closed cycle devices which produce cooling below 120 K. Usually, one or two linear motors are used to drive one pulse tube cryocooler. Cryocoolers are used for various applications like, cooling of infra red detectors, cryo surgical knife, cryogen recondenser etc. In this thesis the design development and testing of Twin Pulse Tube Cryocooler (TPTC) are discussed. TPTC consists of two pulse tubes driven by dual piston head linear compressor. This dual piston linear compressor is operated using single linear motor. Using this configuration, cooling power is doubled with reduced cost of compressor. The design, fabrication and testing of Linear Moving Magnet Synchronous Motor (LMMSM) based dual piston head linear compressor are carried out indigenously. Finite Element Method (FEM) analysis is used for estimating eddy current loss and flux distribution pattern in various mover configurations of the linear motor. The developed fabrication and assembly procedure of linear motor are discussed in detail. The mover of linear motor is supported by using a pair of cross armed C – type flexures. These flexures are designed using FEM and are fabricated indigenously. The flexure pairs are tested for 108 cycles with ± 3 mm stroke length of linear motor before assembling compressor. Linear motor is usually required to be operated at different frequencies. Thus, a variable frequency and variable voltage Pulse Width Modulated (PWM) based power supply is designed using analog circuits like Op-Amps. This cost effective power supply is capable of delivering 27 A at 100 V with frequency range of 25 Hz to 80 Hz continuously. Sage software was used to carry out 1-D simulation and obtain dimensions of various Pulse Tube Cryocooler (PTC) components. Various pulse tube configurations like Joint Twin PTC, Twin PTC with buffer volume and single PTC with buffer volume were carried out. A Computational Fluid Dynamics (CFD) Fluent 2-D analysis was carried out for single PTC with buffer volume. The fabrication and assembly procedure of PTC is discussed in detail. A novel method of heat exchanger fabrication was developed and analyzed using FEM and its performance is tested experimentally. The twin PTC is operated at 34 bar and 48 Hz. A light weight High Temperature Superconductor (HTS) based level sensor is developed to monitor the cryogen level. The developed sensor was calibrated against discrete diode array and pre-calibrated continuous capacitance type level sensor. The calibrations were carried out in indigenously designed and fabricated 4-wall cryostat using Liquid Nitrogen (LN2) and LOX as cryogen. LabVIEW software based data acquisition was designed for testing, recording and monitoring the performance of twin PTC and level sensors during experiments. Advisors/Committee Members: Karunanithi, R (advisor).

Subjects/Keywords: Cryocoolers; Pulse Tube Cryocooler (PTC); Piston Linear Compressor (PLC); Linear Moving Magnet Synchronous Motor (LMMSM); C-Type Flextures; Pulse Width Modulation; High Temperature Superconductor (HTS) Level Sensors; Linear Motors; Flextures; Twin Pulse Tube Cryocooler (TPTC); Liquid Oxygen (LOX) Recondensers; Cryogen Recondensers; Cryogenics; Pulse Tube Cooler; Instrumentation

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Gour, A. S. (2017). Design And Development of Linear Moving Magnet Synchronous Motor Based Twin PTC And HTS Level Sensor for LOX Recondenser. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/2673

Chicago Manual of Style (16th Edition):

Gour, Abhay Singh. “Design And Development of Linear Moving Magnet Synchronous Motor Based Twin PTC And HTS Level Sensor for LOX Recondenser.” 2017. Doctoral Dissertation, Indian Institute of Science. Accessed October 25, 2020. http://etd.iisc.ac.in/handle/2005/2673.

MLA Handbook (7th Edition):

Gour, Abhay Singh. “Design And Development of Linear Moving Magnet Synchronous Motor Based Twin PTC And HTS Level Sensor for LOX Recondenser.” 2017. Web. 25 Oct 2020.

Vancouver:

Gour AS. Design And Development of Linear Moving Magnet Synchronous Motor Based Twin PTC And HTS Level Sensor for LOX Recondenser. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2017. [cited 2020 Oct 25]. Available from: http://etd.iisc.ac.in/handle/2005/2673.

Council of Science Editors:

Gour AS. Design And Development of Linear Moving Magnet Synchronous Motor Based Twin PTC And HTS Level Sensor for LOX Recondenser. [Doctoral Dissertation]. Indian Institute of Science; 2017. Available from: http://etd.iisc.ac.in/handle/2005/2673

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