1. Advisor: Dr. Shangchao Lin
Prototyping and Testing of an Economizer in a Gas Cycled Chiller System
Sponsor:
Dr. Salvador Quitaleg
Team 4 Members:
Steven Hutto
Breck Dorsey
Kenneth Martin
Brandon Van
Guoxin Wang
Advisor: Dr. Shangchao Lin

2. Project Background
A large percentage of energy consumption stems from the need of cooling
Danfoss Turbocor is dedicated to the design, manufacture, marketing and support of the world's most efficient commercial refrigerant compressors
Flash Tank Economizer as a separation chamber
 Economizers implemented into Danfoss’s R&D test rig
Guoxin
2 Guoxin Wang

3. Overall Objectives
 Select between flash tank or heat exchanger economizer 
 Design Cycle 1 - Component design and configuration 
 Design Cycle 2 – Feedback Changes from DC1 and new concepts
 Review DC2 and make any final configuration changes 
 Create Detailed Design Documentation for Custom Prototyping 
 Fabricate two renditions of the final design 
 Burst and Proof Testing for Economizer Standards
Through system cycle calculations on the two types of economizers.
To work hand in hand with the chiller system to always increase efficiency
For burst testing and proof testing which will comply to UL standard
3 Guoxin Wang  

4. Focused Objectives Design Cycle 1 - Component design and configuration
Select between flash tank or heat exchanger economizer
Design Cycle 1 - Component design and configuration
 Design Cycle 2 – Feedback Changes from DC1 and new concepts
Review DC2 and make any final configuration changes
Create Detailed Design Documentation for Custom Prototyping
Fabricate two renditions of the final design
Burst and Proof Testing for Economizer Standards
Through system cycle calculations on the two types of economizers.
To work hand in hand with the chiller system to always increase efficiency
For burst testing and proof testing which will comply to UL standard
4                Guoxin Wang  

5. Introduction to our system
Figure 1: Circuit Diagram for multi-stage compressor using Flash Tank Economizer.
Guoxin
5                Guoxin Wang  

6. Morphological Chart
6               Kenneth Martin  

7. Design Concepts (Morphological Chart)
Requirements
Functional Parameters
Solutions to the Functions
Pressure Vessel Construction
Style
Single Mold
Capped 3 Piece Pressure Vessel
Material
1040 Carbon Steel
Integrate w/ Current Test Rig System
Piping Material
Copper
Schedule 20 Steel
Schedule 80 Steel
Stainless Steel
Pipe Coupling Method
Welding
1:1 Coupler
Expansion Coupler
Throttling Coupler
Effective Control of Economizer
Entrance Valve Control
Digital Buoy Sensor
Mechanical Buoy Sensor
Thermocouple
Thermocouple and Mechanical Buoy Sensor
Expansion Valve Type
Lennox
Danfoss 
Emmerson
Honeywell
Fluid Gauge Systems
Mechanical Dial Gauge
Visual Tube Gauge
Design Concepts (Morphological Chart)
Design 1
7               Kenneth Martin  

8. Design 1 – Capped 3 piece pressure vessel
Saturated Liquid to Evaporator
Vapor To Compressor
Mechanical Buoy System
Baffle Filter
Danfoss Expansion Valve
Mixed State Fluid From Condenser
Horizontal orientation
1-5/8” pipe diameters
1:1 Coupler piping method
Buoy System
Capped ends
Mechanical fluid level gauge
Threaded Capped Ends for Pressure Vessel
Mechanical Fluid Gauge
8               Kenneth Martin  

9. Design Concepts (Morphological Chart)
Requirements
Functional Parameters
Solutions to the Functions
Pressure Vessel Construction
Style
Single Mold
Capped 3 Piece Pressure Vessel
Material
1040 Carbon Steel
Integrate w/ Current Test Rig System
Piping Material
Copper
Schedule 20 Steel
Schedule 80 Steel
Stainless Steel
Pipe Coupling Method
Welding
1:1 Coupler
Expansion Coupler
Throttling Coupler
Effective Control of Economizer
Entrance Valve Control
Digital Buoy Sensor
Mechanical Buoy Sensor
Thermocouple
Thermocouple and Mechanical Buoy Sensor
Expansion Valve Type
Lennox
Danfoss 
Emmerson
Honeywell
Fluid Gauge Systems
Mechanical Dial Gauge
Visual Tube Gauge
Design Concepts (Morphological Chart)
Design 2
9               Kenneth Martin  

10. Design 2 – single mold
Horizontal Carbon Steel Flash Tank Economizer with 1 5/8” copper, to be controlled by a thermocouple control system and a Danfoss expansion valve
Saturated Liquid to Evaporator
Vapor To Compressor
Baffle Filter
Danfoss Expansion Valve
Mixed State Fluid From Condenser
Thermocouple Control System
Visual Tube Fluid Gauge
Danfoss Control Valve
Figure 2: Horizontal Flash Tank
Guoxin
10               Kenneth Martin  

11. Design Concepts (Morphological Chart)
Requirements
Functional Parameters
Solutions to the Functions
Pressure Vessel Construction
Style
Single Mold
Capped 3 Piece Pressure Vessel
Material
1040 Carbon Steel
Integrate w/ Current Test Rig System
Piping Material
Copper
Schedule 20 Steel
Schedule 80 Steel
Stainless Steel
Pipe Coupling Method
Welding
1:1 Coupler
Expansion Coupler
Throttling Coupler
Effective Control of Economizer
Entrance Valve Control
Digital Buoy Sensor
Mechanical Buoy Sensor
Thermocouple
Thermocouple and Mechanical Buoy Sensor
Expansion Valve Type
Lennox
Danfoss 
Emmerson
Honeywell
Fluid Gauge Systems
Mechanical Dial Gauge
Visual Tube Gauge
Design Concepts (Morphological Chart)
Design 3
11               Kenneth Martin  

12. Design 3 – Capped 3 Piece with visual fluid gauge
Saturated Liquid to Evaporator
Vapor To Compressor
Mechanical Buoy System
Baffle Filter
Danfoss Control Valve
Mixed State Fluid From Condenser
Horizontal orientation
1-5/8” pipe diameters
1:1 Coupler piping method
Thermocouple
Capped ends
Visual fluid level gauge
Thermocouple Control System
Threaded Capped Ends for Pressure Vessel
Visual Tube Fluid Gauge
Danfoss Expansion Valve
Figure 2: Horizontal Flash Tank
12               Kenneth Martin  

13. Pugh Matrix Weighted Total 44 40 47 13 Kenneth Martin Criteria
Importance Factor
Design 1
Design 2
Design 3
Safety 5 2 3
Performance 4
Reliability
Ease of Use
Cost 1
Maintenance
Weighted Total 44 40 47
Kenny
13               Kenneth Martin  

14. Concept Evaluation Weighted Total 44 47
Design 1 vs Design 3: Mechanical Fluid Gauge vs Visual Tube Gauge
Design 1 vs Design 3:Buoy Control System vs Thermocouple Control System
Design 1 vs Design 3: Mechanical Control vs Electrical Control System
Design 1 & Design 3 utilize a 3 piece pressure vessel
Design 1 & Design 3 can be accessed via the capped sections in order to maintain the system over time
Criteria
Importance Factor
Design 1
Design 3
Safety 5 2 3
Performance 4
Reliability
Ease of Use
Cost 1
Maintenance
Weighted Total 44 47
14               Kenneth Martin  

15. Pugh Matrix Weighted Total 44 40 47 15 Kenneth Martin Criteria
Importance Factor
Design 1
Design 2
Design 3
Safety 5 2 3
Performance 4
Reliability
Ease of Use
Cost 1
Maintenance
Weighted Total 44 40 47
Kenny
15               Kenneth Martin  

16. Flash Tank Specifications Size Material Vessel shape
Diameter
Length
Volume
Material
Vessel shape
Special opening closures
Quick opening heads(Autoclaves)
Pressure and Temperature ratings that determine wall thickness
Price
~$4000 per tank 
Breck
16               Breck Dorsey

17. Baffle Filter Also called a demister or De-entrainment mesh
Mounted at the 1-5/8"outlet pipe leading to compressor
Separates gas from liquid to avoid damage to compressor blades and to increase efficiency
 Effective at collecting 100% of particles larger than 8 microns diameter
How it works
1. Vapor stream carrying entrained liquid droplets passes through demister and vapor moves freely through mesh
2. The inertia of the droplets causes them to contact the wire surfaces and coalesce
3. The large, coalesced droplets formed in the mesh ultimately drain and drop to vessels bottom
Price ~$250 
Breck
17               Breck Dorsey 

18. Control Valve & Thermocouples
Supplied by Danfoss Turbocor
 How it works
Superheated vapor temperature measured by thermocouples is related to the fluid level in flash tank
Control valve operates to maintain a desired level of fluid, so that a constant rate of liquid is sent to evaporator
KVS 42, suction modulation control valve
1-5/8" inlet and outlet
Price ~$50 - control valve
            $60 - thermocouples
Breck
18               Breck Dorsey 

19. Potential Challenges CAD construction of overall design
Cost evaluation for design
Material and component acquisition
Compatibility of systems/assembly
Control system testing
19               Breck Dorsey 

20. 3 Month Project Plan Major Activities Completed Two Week Look Ahead
Chiller and Economizer Research
Computational Analysis of the Economizers
 Design cycle 1 & 2
Two Week Look Ahead
Design cycle 2 review
Design Finalization
Detail Design Documentation
Prototyping Plan
20               Breck Dorsey 

21. Conclusion
 Horizontal orientation allows for a larger baffle filter, which promotes more effective liquid vapor separation 
 Carbon steel is a good material for construction of
  tank
 Estimated cost is approximately $8360
  (not including labor)
21              Breck Dorsey 

22. References
[1] "ThermoFlo User Manual." ThermoFlo User Manual, n.d. Web. 20 Oct
[2] "Chapter 11." SpringerReference (n.d.): n. pag. Web.
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