Cryogenic Engineering Education at NIT Rourkela

Cryogenic Engineering
Education at NIT Rourkela
Sunil Kr Sarangi
Director, NIT Rourkela
NIT Rourkela
• Established in 1961 as the Regional
Engineering College
• Converted to National Institute of
Technology in 2002
• 9 Engineering, 3 Science and 1 Social
Science Departments
• Faculty: 180 (120); Students 1700;
Supporting Staff 350
Department of Mechanical
Engineering
• Faculty Strength : 25 (17)
• Students :
– B Tech : 80 x 4
– M Tech :
– Machine Design
– Production Technology
– Thermal Engineering
– M Tech by Research
• Ph D Programme
Refrigeration & Cryogenics Group
Prof Sunil Kr Sarangi
Prof Ranjit K Sahoo
Prof Ashok Satpathy
Prof Alok Satpathy
Prof Subhas Haldar (on leave)
Cryogenic Engineering Laboratory
Major Equipment
• Cryomech Liquid Nitrogen Generator
Based on GM refrigerator
– Capacity 40 litre per day
• INOX Dewars
– 200 litre (5 bar), 2 x 30 litre, 3 litre
• Thermax steam generator
– 500 kg/hour, 10 bar
• Vacuum Techniques (Bangalore) High
vacuum pumping station - 500
litre/second
• Alcatel Vacuum Leak Detector
• Miscellaneous Instruments
Cryogenic Engineering Laboratory
R&D Activities
•
•
•
•
•
Screw compressor (BRNS)
Expansion Turbine
Heat Exchangers
Heat and Mass Transfer
Programmable Cryochamber for Cryotreatment of
Cutting Tools
• Pulse Tube Refrigerator
• Laboratory nitrogen liquefier and refrigerator
• Helium Purifier
STUDIES ON OIL INJECTED
TWIN-SCREW COMPRESSOR
STUDIES ON OIL INJECTED TWINSCREW COMPRESSOR
¾ Development of a Mathematical model to relate the
performance of a screw compressor to design and
operating parameters.
¾ Conversion of a cheap Air compressor for Helium
applications.
¾ Study of purification techniques to ensure oil free gas
delivery suitable for cryogenic applications
Animation of 5-6 lobe combination rotors; casing removed for clarity
Suction
Entrapment
Compression
Discharge
Working mechanism of twin screw compressor
Schematic view of experimental setup at NIT Rourkela
100
Air
Nitrogen
Argon
Helium
Pd/Ps=8.65;RPM=4350
94
88
(ηtv %)
82
76
70
64
58
52
46
40
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
Interlobe clearance(mm)
Comparison volumetric efficiency of different gases at a fixed
male rotor rotational speed with interlobe clearance at a fixed
injected oil temperature and suction conditions
96
T li=308K
94
(ηv %)
92
90
Air(exp)
Air (calculated)
Nitrogen(exp)
Nitrogen(calculated)
Argon(exp)
Argon(calculated)
Helium(exp)
Helium(calculated)
88
86
84
2
3
4
5
6
7
8
Pressure ratio(Pd/Ps)
Variation of volumetric efficiency of different gases with
pressure ratio at a fixed injected oil temperature and suction
pressure
9
Development of a Cryogenic
Turboexpander
Development of a Cryogenic
Turboexpander
¾
The Expansion turbine is a basic component of a
Cryogenic process plant
Air separation plant
Helium or hydrogen liquefier
Low temperature refrigerator
NIT,Rourkela has initiated a program for
indigenous development of a turboexpander, in
continuation of earlier work at IIT Kharagpur
¾
17 blades equispaced
Blade details
4 Slots of 10mm width
Experiments with
SINGLE STAGE PULSE TUBE
REFRIGERATOR
SINGLE STAGE PULSE TUBE
REFRIGERATOR
‰ OBJECTIVES:
¾ Design and development of single stage pulse tube
refrigerator
¾ Development of rotary valve pressure pulsation
¾ Development of Helium compressor
‰ PRICIPLES OF WORKING
¾ The gas must reach the low temperature point without
carrying a lot of heat.
¾ The amplitude of the gas flow and pressure oscillations in
the pulse tube section must be large enough to carry away
the heat collected by to the cold heat exchanger, and
¾ The phase relationship between the pressure and the gas
flow in the pulse tube section must be appropriate to carry
heat away from the cold point
Programmable Cryochamber
Programmable Cryochamber
Programmable Cryochamber
• Features:
– Working volume = 300 x 300 x 300 mm
– Temperature controlled to about 1 K by PID
control
– Temperature range: 300K to 90K
Programmable Cryochamber
Components
–
–
–
–
–
–
–
Stainless Steel Housing
Thermocole insulation
Cryogenic solenoid valve
Fan for air circulation
Heater
RTD Temperature sensor
ADAM data acquisition modules
Programmable Cryochamber
Applications
– Good for Cryotreatment of cutting tools, dies,
punches
– Poor in biological applications because of direct
spray of liquid nitrogen and lack of seeding
facility.
Major New Initiatives
Experiments on Brazed Aluminium
Plate Fin Heat Exchanger
Heat exchanger test core with steam entry
and exit ducts ( IIT Kharagpur)
Photograph of the experimental rig at IIT Kharagpur ;
New programme initiated at NIT Rourkela.
0.1
f - factor
10.2 W 0.152 18 (Al)
2/3
St.Pr
f (Hot Test)
j - factor
2/3
St.Pr (Kays)
f (Kays)
f (Cold Test)
0.01
0.5 0.6 0.7 0.80.9 1
2
Re x 10
3
4
5
6
7
8 9
-3
Thermo-hydraulic characterization of the calibration
heat exchanger (IIT Kharagpur results )
Development and Study of an Indigenous
Helium Purifier based on Low Temperature
High Pressure Adsorption of Impurities
( Submitted to BRNS )
INVESTIGATORS
PI: Prof Sunil Kr Sarangi, NIT Rourkela
CI: Prof Ranjit K. Sahoo, NIT Rourkela
Prof P. K.Das, IIT Kharagpur
PC: Mr. R.Dey, VECC, Kolkata
Mr. Trijit K.Maity, VECC, Kolkata
• In
liquid
helium
applications
(e.g.
superconducting magnets), boil-off helium gas is
collected in gas bags, compressed and reliquefied.
• In the process, the gas is contaminated with air
impurities (nitrogen, oxygen, moisture, CO2)
• Removal of impurities is essential to avoid
blockage of orifices and valves, deposition on
heat transfer surfaces and solid impurities hitting
turbine blades.
• On-line purifiers are often inadequate to handle
high impurity concentrations.
Project Objectives
– To design and build an adsorption based helium
purifier, and to study its performance
– To create proper documentation (design details,
selection of equipment, fabrication and testing
methods) for future construction and
technology transfer.
Specifications :
Raw gas flow rate
= 20 m3/hr.
Adsorption pressure
> 120 to 150 bar.
Adsorption temperature
= 77 K.
Inlet impurity conc. = upto 50%air in helium.
Outlet impurity
< 100 ppm air in helium.
Elements of the Proposed Project
1. Determination of specifications of the purifier.
2. Process design.
3. Component specifications.
4. Design or selection of components.
5. Procurement and fabrication of components.
6. System integration.
7. Testing and performance studies.
8. Improvement of design.
9. Documentation.
10. Technology Transfer.
Selection of Equipment :
Compressor : 1 bar to 150 bar, 3 or 4 stages
Reciprocating
Flow rate = 20 m3/hr
Options: Bauer (Germany)
John Sauer (Germany)
TEC (Korea)
Helium Purity Monitor - Imported
Vacuum Vessels – Fabricated commercially
Valves & Fittings – Swagelok, Parker
Other accessories – To be procured
Experimental Programme :
•
•
•
•
•
•
Actual impure helium flow rate and pressure drop in
different components.
Actual product purity (expected purity 99.99%) as a
function of input purity level.
Maximum tolerable air impurity.
Maximum tolerable moisture impurity.
Capacity of purifier (nm3 of pure helium) before
regeneration as a function of input purity.
Liquid nitrogen consumption
–
–
•
quantity of LN2 consumed per regeneration cycle.
quantity of LN2 consumed per nm3 of pure helium as a function of
input impurity.
Time and power input for regeneration.
Deliverables :
• Two completely functional purifier units
delivering 99.99% pure helium, 50 to 100
m3 per six-hour shift. [One unit will be
delivered to VECC, while the other is
retained in the PI’s laboratory].
• A well documented design and fabrication
procedure, and
• Complete performance study along with
comparison with theoretical prediction.
DEVELOPMENT OF TURBOEXPANDER
BASED CRYOGENIC REFRIGERATOR AND
LIQUEFIER
( Submitted to BRNS )
INVESTIGATORS
PI: Prof Sunil Kr Sarangi, NIT Rourkela
CI: Prof Ranjit K. Sahoo, NIT Rourkela
CI: Prof G. Venkatarathnam, IIT Madras
PC: Mr. Trilok Singh, Head, Cryogenic
Division, BARC
He
Gas Bag
1
Compressor
3
2
4
5
Aftercooler
9
8
Load
Turbine
7
Load
6
Turbine
Heat Load
Cryogenic refrigerator (Tref > 4.2 K) based
on modified Collins cycle: Process Flow
Diagram
p=
Compressor
HX1
9
3
Temperature (T) [K]
LP
HP
p=
2
1
HX2
4
5
8
HX3
7
EE
p
P
=H
p=
Heat Load
6
LP
Specific Entropy (s) [J/kg. K]
Cryogenic refrigerator (Tref > 4.2 K) based
on modified Collins cycle: Temperature
Entropy Diagram
Constituents of a Cryogenic process plant
Hardware
1. Compressor (Reciprocating or Screw)
2. Heat Exchangers (wound finned tube, plate fin,
matrix)
3. Expansion engine/turbine
4. Expansion (JT) valve
5. Plumbing
6. Instrumentation and controls
7. Vacuum vessels
Brainware
8. Process Design
9. Selection of equipment
10. System integration
11. Operation and testing
The Proposed Project
Target :
1. To construct a turbine based refrigerator with
following specifications :
-
Working Fluid
:
-
Ultimate Temperature :
50K
-
Cooling Load
2 kW at 80K
:
Helium
2. To use the same device with Nitrogen as working
fluid to realize a laboratory scale liquid nitrogen
generator. Expected production rate: 20 lit/hr
The Proposed Refrigerator System
Gas Bag
1
Cold Box
7
Compressor
Aftercooler
2
3
6
5
Load
Turbine
4
Nitrogen
Heat Load
Proposed Cryogenic refrigerator (Tref = 80 K) based on Reverse
Brayton cycle and using a heat exchanger of effectiveness less
than unity: Process Flow Diagram
LP
p=
HP
p=
Temperature (T) [K]
2
1
7
Compressor
6
HX
3
EE
HP
p=
LP
p=
H
5
d
4 Lo a
t
ea
Specific Entropy (s) [J/kg. K]
Proposed Cryogenic refrigerator (Tref = 80 K) based on Reverse
Brayton cycle and using a heat exchanger of effectiveness less than
unity: Temperature Entropy Diagram
Liquid Nitrogen Generator
Air Purifier
Raw Air
Dry air
(CO2 free)
1
Cooling
water
Compressor
Isothermal
2
3
HX1
4
HX2
8
5
7
HX3
Expansion
Engine
Load
EE
g
Phase
Separator
Expansion
Valve
6
f
Liquid
Air
Air/Nitrogen liquefier based on Claude cycle
and using ideal heat exchangers: Process
Flow Diagram
LP
HP
p=
p=
2
Compressor
1
Temperature (T) [K]
HX1
8
3
HX2
EE
5
4
Exp valve
h = Constant
HP
p=
LP
p=
f
6
Phase separator
7
HX3
g
Specific Entropy (s) [J/kg. K]
Air/Nitrogen liquefier based on Claude cycle and
using ideal heat exchangers: Temperature Entropy
Diagram
Components of Proposed Refrigerator and
Liquefier
•
•
Compressor : Existing Screw Compressor
Make : Kaeser, Germany
Pressure Rating : 10 bar
Flow Rate : 300 m3/hr
Power : 37 KW
Working Fluid : Nitrogen / Helium
Expander :
Technology developed for turbine of matching
capacity with gas lubricated bearings.
Needs more work : fine tuning, reliable operation,
performance improvement.
•
Heat Exchangers :
Plate fin heat exchangers to be procured from
BHPV, Vishakhapatnam, or Apollo heat
exchangers.
Design capability exists at NIT.
Propose to try wire-wound coiled tube and
printed
circuit heat exchangers.
•
Plumbing, Instrumentation & Controls :
To be procured.
•
Vacuum Vessel, insulation etc :
To be procured.
•
Process Design :
- Capability available at NITR and IIT Madras.
•
System Integration, Operation and Improvement :
- to be pursued as part of the project.
The future :
• Fully established indigenous technology on
turbine based refrigerators and liquefiers
–
–
–
–
Laboratory scale nitrogen generator
10-20 K Refrigerator
Laboratory scale helium liquefier
Liquefiers for hydrogen, natural gas and special
gases
Thank You