understanding applications for alternate refrigerants · 2019-04-08 · r-448a/r-449a refrigerant...

Understanding Applications for Alternate Refrigerants

Ron BonearEmerson Climate Technologies

Agenda

Overview of R-448A/R-449A Refrigerant Development Methodology

– Evaluation Strategy — R-448A /R-449A Refrigerants

Performance Development

– Thermophysical Comparison of Refrigerants

– Refrigerant Performance

Reliability Evaluation

– Effect of New Refrigerants on Compressor Components

– Reliability Assessment

R-448A/R-449A Development Summary and Conclusions

Brief Update on Alternate Refrigerants — R-450A/R-513A and R-452A

Update on ECT’s Alternate Refrigerant Facilities Development Plan

R-448A/R-449A Refrigerant Evaluation Methodology

Alternate Refrigerant Evaluation — Performance

– Focus on Developing Fast/Flexible Refrigerant Release

Sidney Refrigeration Engineering Team Developed Test

Strategy for Simultaneous Approval of R-448A and R-449A

– Equivalent Chemical Composition Between the Two

Refrigerants

Thermophysical Comparison, Miscibility and Compatibility

Analysis Performed on R-448A/R-449A

UL Qualification Strategy

Objective: Reduce UL Qualification Time

– Due to Chemical Equivalency of Refrigerants, UL Agreed to Full Model Line

Approvals of Both R-448A/R-449A by Testing Only R-448A

– Testing Required to Show That R-448A MCC Amp Values Were ≤ +10%

Above R-404A

– In All Instances, R-448A Met This Criteria

The Majority of MCC Values Fall Below That of R-404A

– As a Result, R-448A Has Been Released Using Existing R-404A MCC Values

By Utilizing This Approach, It Was Possible to Significantly Reduce the Total

Number of Compressors Tested:

8 Scroll Compressors

6 Semi-Hermetic Compressors (4 Discus / 2 KEL)

Alternate Refrigerant Evaluation — Reliability

– Evaluation of the Interaction of Refrigerants With Oil

Miscibility/Solubility/Viscosity

– Bearing Analysis Performed Using Mobility Analysis

– Full Operating Envelope and Reliability (CFM) Testing

Performed Using R-448A/R-449A

R-448A/R-449A Refrigerant Evaluation Methodology

Agenda












Evaluation of Alternate Refrigerant Performance

Evaluation of R-448A/R-449A Relative to Existing Medium-

Pressure Refrigerants

– Evaluate Equivalency of R-448A Relative to R-449A

Evaluate Refrigerant Chemical Compositions

– Evaluate R-448A Relative to R-404A and R-407A

Thermophysical Comparison of Refrigerants

– Pressure Differential

– Density

– Enthalpy

Refrigerant Performance Testing Comparison

Evaluation of Refrigerant Chemical Composition

R-448A/R-449A Relative Comparison

– Both R-448A and R-449A are medium-pressure, A1 refrigerants

Verify chemical composition ± 5%

Honeywell R-448A Composition DuPont R-449A Composition

R-32 (26%)

R-125 (26%)

R-134a (21%)

1234yf (20%)

1234ze (7%)

Determination Made That the Two Refrigerants Are

Effectively Chemically Equivalent

R-32 (24%)

R-125 (25%)

R-134a (26%)

1234yf (25%)

Evaluation of Refrigerant Pressure Differential

Evaluate R-448A ∆P to R-404A/R-407A

R-448A exhibits a lower pressure differential than R-404A. R-448A

compressor loads will be lower.

R-448a and R-407A have essentially identical pressure differentials.

Evaluation of Refrigerant Density

Evaluate R-448A Density Relative to R-404A/R-407A

Evaluation of Refrigerant Enthalpy

Evaluate R-448A Theoretical Enthalpy Relative to R-404A/R-407A

Scroll MT — Mid/Dew Point CapacityR-404A Versus R-407A/R-448A (20/70)

Scroll MT — Mid/Dew Point CapacityR-404A Versus R-407A/R-448A (20/120)

Scroll LT — Mid/Dew Point CapacityR-404A Versus R-407A/R-448A (-25/70)

Scroll LT — Mid/Dew Point CapacityR-404A Versus R-407A/R-448A (-25/105)

Scroll MT — Mid/Dew Point Weighted EERR-404A Versus R-407A/R-448A

Scroll LT – Mid / Dew Point Weighted EERR-404A Versus R-407A / R-448A

R-448A/R-449A Operating Envelopes —Summary and Conclusions

Following Operating Envelope Testing and CFM, R-448A/R-449A Will

Use Same Envelope as R-407A

R-448A/R-449A Demonstrated Thermophysical Equivalence

Discharge Line Temperatures Are Similar to But Slightly Higher Than

R-407A at HCR/MDP Conditions

– Reliability Testing Confirms Higher Temperatures at Envelope Corners

Are Acceptable

» Only Map Affected Is ZBK5 Envelope

All R-448A/R-449A Are the Same Envelopes as R-407A

Only Exception Is ZBK5 Envelope, With Slightly Reduced HCR

Corner Point

Final R-448A/R-449A MT K5 Operating Envelope

Agenda












Refrigerant Reliability Evaluation

Refrigerant Reliability Assessment

– Reliability

Bearing Analysis

– Miscibility

– Solubility/Viscosity

– Mobility Analysis

DFMEA

– High RPN Failure Modes Drive CFM Test Strategy

CFM Testing Summary

Refrigerant Reliability Evaluation

Reliability Development Envelope

Miscibility Evaluation

Viscosity Evaluation

Mobility Analysis of R-448A Relative to R-404A

R-448A/R-449A CFM Summary

Evaluated Full Range of Compressors Using Standard Reliability

Engineering Procedure

Performed CFM Testing at Envelope Corner Points

– HCR

– MDP

– High Load

Flooded Start and Defrost Cycles Tested to Verify Miscibility

– Ensure Full Hydrodynamic Bearing Film Thickness Following

Refrigerant Washout

Mobility Used to Validate Minimum Oil Film Thickness to

Surface Finish Ratio (ʎ)

– R-448A/R-449A Meets or Exceeds ʎ for R-404A

All Scroll/Semi-Hermetic Compressors Passed Full Battery of CFM Testing

Agenda












R-448A/R-449A Summary and Conclusions

From R-448A/R-449A Qualification, the Sidney Refrigeration Engineering

Team Has Utilized a Standardized Test Strategy for New Refrigerants

- Comparative Evaluation of Refrigerant Properties

- Full UL, Performance, Operating Maps and Reliability Testing

Thermophysical Similarity of R-448A and R-449A Has Been Verified

The Thermophysical Properties of R-448A Are Much Closer to

R-407A Than R-404A

- R-404A Is Much Denser Than R-448A; Higher Mass Flows

- R-448A Exhibits Lower ∆P; Lower Bearing Loading Than R-404A

- R-404A Capacity Significantly Greater Than R-448A at LT Conditions,

Roughly Equivalent on MT Applications

R-448A/R-449A Summary and Conclusions

R-448A/R-449A Operating Envelopes Are Equivalent to Current R-407A

- Ref ZB*K5 HCR Condensing Will Be Slightly Reduced to

Accommodate R-448A/R-449A and R407A on One Map

Bearing Analysis Performed by Evaluating Miscibility/Viscosity, Loads,

M Mobility Analysis and CFM

Comprehensive R-448A/R-449A Performance and Reliability

Evaluation Complete

Captured Lessons Learned in Standardized Document

- Utilized for All New Refrigerant Releases

Accuracy and Completeness of Data for Both Performance and

Reliability Are Assured

Agenda












Update on R-513A/R-450A and R-452A

Performance and Initial Reliability Evaluations Underway for Low-

Pressure R-513A/R-450A (Europe and U.S.) and for Medium-Pressure

R-452A (U.S., Transport Scroll Only)

– Preliminary Performance Evaluation for Refrigerants Complete

– Initial Reliability Assessments of Both R-452A and R-513A Indicate

Higher Solubility Index May Pose Challenge for Compressor Boundary

Lubrication

Higher Solubility Reduces Oil Viscosity and May Affect Boundary

Lubrication During Liquid Applications

– Currently Evaluating Alternate, Higher Viscosity Oil as

Countermeasure

R-450A/R-513A Refrigerant Performance —Capacity

R-450A/R-513A Refrigerant Performance —EER

R-452A Refrigerant Performance — Capacity

R-452A Refrigerant Performance — EER

Agenda












Recap of Alternatives for Refrigeration Applications

R-410A

Like

Capacity

R-404A and

R-407/22

Like

R-134a

Like

GWP Level

400–675

< 1,500

~600

~300

HFO 1234yf

HFO 1234ze

ARM-42

R-410A

R-22

R-407A

R-407C

R-407F, R-452A = XP44

AR M-35

0 500 1,000 1,500 2,000

Pressure

or

R-32/HFC/HFO

Blends

R-32/HFO

Blends

HFC/HFO

BlendsR134a

CO2

R-404A

R-507A

DR2, N12, ARC 1

R290

NH3

A1 – Non-Flammable

A2L – Mildly Flammable

A3 – Flammable

R-123 Like

(V. Low Pr.)

(3922)

R32

R-32/HFO

Blends

R-448A = N40

R-449A = DR33

R-449B = ARM-32

N20

R-450A = N13

R-513A = XP10

R-444B = L20

L40, DR7

ARM-20b

HDR110

DR3

ARM-20a

R-446A, R-447A, ARM-71a

<150

B2L – Toxic, Mildly Flam.Qualitative – Not to

Scale

1

Building

23

2015

42016

Emerson’s A3 / A2L Facilities Development Plan

Selecting a TXV for

Use With R-448A /

R-449A / R-513A

Brad HopsonEmerson Climate Technologies

TXV Selection Review

1. Refrigeration Type

2. Evaporator Temperature/Pressure

3. Evaporator Capacity

4. Condensing Temperature/Pressure

5. Liquid Temperature

6. Distributor Type (if used)

Note: The valve is sized to the evaporator and not the compressor.

Glide and the p-h Diagram

Zeotropic Blends Exhibit Glide

Calculating Delta P at

Expansion Device:

– Bubble Point (Saturated

Liquid) for Condensing

Pressure

– Dew Point (Saturated

Vapor) for Evaporating

Pressure

TXV Pressure Differential

This Is Also the Delta P at the Expansion Device

Lower Delta P Generally Lowers Valve Capacity

In the Given Applications, the Change in Pressure Differential Is Very Small

Superheat Curves (and Other Secrets)

Evaporator Temp.

Supe

rheat

R-404A Bulb Charges Are NOT Optimized for R-448/449

Superheat Settings MUST Be Adjusted

At Low Temps, the Superheat Tends to Rise

Low-Temp. Valve Capacity Adjustment

Low-Temp. Applications Require Larger Valves

In Practice, Choose a Valve With 50% More Capacity

Summary

Pressure Differential:

– Use Bubble Point for Condensing Pressure

– Use Dew Point for Evaporating Pressure

R-513A — Use R-134A Tables

R-448A/R-449A

– Medium-Temp – Very Similar to R-404A

– Low-Temp – Select Approximately 50% More Capacity

Thank You!

DISCLAIMER

Although all statements and information contained herein are believed to be accurate and reliable, they are presented without guarantee or

warranty of any kind, expressed or implied. Information provided herein does not relieve the user from the responsibility of carrying out its

own tests and experiments, and the user assumes all risks and liability for use of the information and results obtained. Statements or

suggestions concerning the use of materials and processes are made without representation or warranty that any such use is free of patent

infringement and are not recommendations to infringe on any patents. The user should not assume that all toxicity data and safety measures

are indicated herein or that other measures may not be required.

Questions?

understanding applications for alternate refrigerants · 2019-04-08 · r-448a/r-449a refrigerant...

Documents