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Indigenous Development of Helium Liquefier and Cyclic Refrigerators. P K Kush Head, Cryo Engineering and Cryo Module Development Section Raja Ramanna Centre for Advanced Technology , Indore, INDIA
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Indigenous Development of Helium Liquefier and Cyclic Refrigerators P K Kush Head, Cryo Engineering and Cryo Module Development Section Raja Ramanna Centre for Advanced Technology, Indore, INDIA Email: kush@rrcat.gov.in Web: www.rrcat.gov.in
Components of a Helium Liquefier • Expansion Devices • Heat Exchangers • Thermal Insulation system (Cold Box) • Process Control Components • Thermally Insulated Transfer Lines • Main Dewar (To collect Liquid) • Cyclic Compressor
Cryogenic Expansion Engine Expansion Engine: A Critical part in Claude/ Collinscycle based cryogenic refrigerators and liquefiers Types of Expansion Engines Reciprocating Type Turbine Type Reciprocating Type Expansion Engine • High Expansion Ratio • Low Flow Rate • Constant Efficiency Over Wide Range of Operating Conditions. • Less Sensitive to Contamination and Power Fluctuation Problems • Control of Speed/ Flow Rate is Easier
Expansion Engines 3D Model of expansion engine developed at RRCAT Photograph showing expansion engine along with heat exchangers and auxiliary components. 1. Cryogenic Expander, 2. Work extraction mechanism, 3. 1st heat exchanger, 4. Flywheel
Expansion Engines Actual P-V Diagram, near Room Temperature Expansion Cycle Actual P-V Diagram, at low Temperature
Expansion Engines Graph showing condition when both Inlet and exhaust valves are leaking Distorted P-V Diagram due to valve leakage Graph showing condition better leak tightness of valves
Expansion Engines Stress analysis of expander liner Temperature profile using 80K anchoring Temperature profile
Heat Exchangers • Low losses of use full refrigeration through • Heat Conduction through solid material – long length • Through radiation – lower surface area • Very low pressure drops – critical pressure for helium: 2.2 bar absolute • Heat Transfer – One side high pressure helium (about 230 psig) – Other side Very low pressure Helium (about 2 psig) 300 K 80 K
Heat Exchangers Photograph of heat exchanger HX-6 before final welding
Make: Sulzer India, Four Stage, air cooled, oil Lubricated, Reciprocating type (Suitably modified for using it with above expansion engine)Oil Removal System: Designed, Processed and commissioned by us. (Fabricated by local fabricator) Cyclic Compressor
Process Integration of Components • Cyclic Compressor • Suitable compressor lubricating oil • Efficient oil removal system • Quality welding and brazing – problem of “cold leaks” • Processing of components • Pressure Control and Helium Gas management system – 740 liters (NTP) produces 1 liter liquid
Liquefaction Temperature reading of the sensor put inside the liquid helium collection container after J-T valve, when liquefaction was approached for the first time.
Present Status • Helium Liquefier developed at RRCAT has been operated more than 6 times so far • Each time it was operated till the main Dewar was filled to safe limit - 200 liter • Nearing 1,000 hours of operation – no breakdown
Team Members Samir Ranjan Sardar, Om Prakash, Krishna Kant Mahawar, Ravindra S. More, Pawan Kumar, Radha Krishan Pathak, Nakka Sathi Babu, S K Joshi, Ashok Kumar Dewangan, M S Ansari, Ravi Sharma, Chetan Singh Sunil Kamthre.
Development of Cyclic Refrigerators 30 K Cryocoolers 10 K Cryocoolers Cryopump with pumping speed of 1,200 liters/sec for air
Cryocoolers like domestic refrigerator require only electricity to produce low temperature. The Cryocoolers developed at RRCAT are based on Gifford McMahon Cycle. They produce 30K in a single-stage system and 10K in a two-stage system. The entire cryocooler is made of indigenously available components. • The Cryocooler consist of two parts, an expander module and a compressor module. • The Cryocooler uses Helium gas as working fluid.
Development of Cyclic Refrigerators 30 K Cryocooler 10 K Cryocooler
3D Design Model Product Photograph
Reference: “Low-power cryocooler survey”,H.J.M. ter Brake, G.F.M. Wiegerinck, Cryogenics 42 (2002) 705–718. (Data of 235 cryocoolers made world wide) Cryocooler developed by RRCAT: Compressor power 2.19 kW. Cooling power 27.89 w at 80 K
30 K CCR supplied to user Labs. 06 Numbers of 30 K systems are supplied to different labs + One Compressor Module matched with imported unit and supplied to BARC, Mumbai, Year 2002.
(1)One 30 K Cryocooler supplied during first half of year 2004 (Laser Physics Applications Division, RRCAT), It is being used for study of “Temperature Dependent Transient Photoconductivity & Photoluminescence of Organic Semiconductors” Sample Holder
(2)Another 30 K Cryocooler was supplied to Semiconductor Laser Section, RRCAT during year 2004. It is being used to study “Temperature Dependent Electrical Transport measurements • Hall Mobility, Carrier Concentration, Resistivity • Study of J – V and e – V characteristics at low Temperature • On semiconductors thin films and optoelectronic structures like lasers, detectors – Regularly grown using MOVPE system at RRCAT
(3)Another 30 K Cryocooler was supplied to Laser Physics Applications Division, RRCAT. It is being used to study “Temperature Dependent Carrier Dynamics measurements by Ultra Fast Pump Probe Spectroscopy”
(4)One 30 K Cryocooler is coupled to a specrofluorometer of Jobin-Vyon (Model no- Fluoromax-3) suitable for experiments in Temperature range of 40 to 300K. This is being used in a Photoluminescence setup at BARC Spectroscopy Lab RRCAT Indore.
(5)Another 30 K Cryocooler was supplied to Materials, Advanced Accelerator Science Div.: , RRCAT. On this Cryocooler a cryogen free ac-susceptometer working over a wide temperature range (30-400K) is developed. Which amongst other things is capable of precision measurements of phase transition phenomenon in magnetic materials and superconductors.
(6) Materials, Advanced Accelerator Science Div.: Resistivity versus Temperature Measurements.
10K Cryocooler Lowest Temperature – < 8 K Temperature Stability - ± 0.5 deg
Cryocoolers Developed at RRCAT One cryocooler producing a minimum temperature of 7K is installed in Photophysics beamline at Indus-1 for Matrix Isolation Spectroscopy setup being developed by BARC and IGCAR. 3D Model during Designing Product Photograph
Cryopump Using Our 10K G-M Cryocooler • Ultimate Vacuum: 4 x 10E-8 mbar • Pumping Speed • Nitrogen: 1200 Liter/sec • Argon: 900 Liter/sec • Max. Throughput: 2 mbar. Liter/sec • Impulsive gas load (Cross over) Tolerance: 60 mbar-Liter • Gas Capacity for Nitrogen: 300 Std. liters
Compressor Modules Developed at RRCAT Problems Related with Helium Compressor: • Helium gas compressors of suitable size are not available in open market. • High heat of compression for Helium Gas • Suitable Lubricating Oil for clean operation • On line Oil removal system for ultra clean high pressure Helium gas All the above problems solved by modifying Commercially available Air-Conditioner Compressor for helium gas. Completed more than 3,000 hours of operation.