Mauro Dallai Milano – 16th March 2016 1

OFFICINE MARIO DORIN S.p.A.

NxtHPG project

CO2 transcritical compressors

for case studies 4 and 5

MCE Workshop – 16th March 2016

“This project has received funding from the European Union’s Seventh Programme for research, technological development and demonstration under grant agreement No [307169]”.

Mauro Dallai Milano – 16th March 2016 2

Heat pump at case study 4

Case Fluid Source Tamb(ºC) Sink T(ºC) Application (kW)

1 HC (Propane) Air

-10 to 35

(outdoor air) Water

40 to 50 Heating water production 40

60 Low demand of Domestic hot water

2 HC (Propane)

Water (brine) -5 to15 Water

40 to 50 Heating water Production

60 60 Low demand

of Domestic hot water

3 HC (Propane)

Water (Neutral

loop)

10 to 15 (Sewage water) or 25 to 30

(Condensation loop)

Water 60 Domestic hot water production 50

4 CO2 Air -10 to 10 (winter)

20 to 35 (summer) (outdoor air)

Water 60 to 80 Domestic hot water production 30

5 CO2 Air -10 to 35 (outdoor air) Water

80 (return water

40)

Heating & domestic hot water production 50

Mauro Dallai Milano – 16th March 2016 3

Heat pump at case study 4

Main characteristics are:

•  single stage transcritical compressor •  2-cylinders bore 34 mm stroke 30 mm •  swept volume 5,61 m3/h at 50 Hz •  motor 380-420V/3/50Hz PWS •  max operating current 24 A •  design pressure: LP 100 bar

HP 150 bar

Installed compressor: model CD1000H

Mauro Dallai Milano – 16th March 2016 4

Test results of experimental campaign in Enea

•  Operating conditions of the compressor in heat pumps are very variable

•  They depend largely on: Ø  ambient temperature Ø  water inlet temperature •  Unlike the refrigeration

applications, which work in conditions fairly stable throughout the year, in heat pumps, evaporating pressure can vary from -20°C up to +15°C

Tambient=2°C

10

15

20

25

30

35

40

45

50

80 85 90 95 100 105 110

p_out_CP  [bar]

P_in_C

P  [bar]

2014_07_10_Tin10_Tout55_Tccm7_matrix

2014_07_08_Tin10_Tout55_Tcc2_matrix

2014_07_14_Tin9_Tout65_Tcc7_matrix

2014_07_02_Tin15_Tout60_Tcc12_matrix

2014_07_01_Tin20_Tout60_Tcc15_matrix

2014_07_02_Tin17_Tout65_Tcc16_matrix

2014_06_27_Tin30_Tout60_Tcc20_matrix

2014_06_27_Tin30_Tout80_Tcc20_matrix

2014_07_16_Tin50_Tout60_Tcc20_pgc105

Test at ambient temperature +2°C

Tin_water = 10÷50°C; Tout_water = 10÷50°C

Heat pump at case study 4

Extreme variability in the operating

conditions

Mauro Dallai Milano – 16th March 2016 5

CD-H compressors design solutions

Thanks to adopted design features, of CD-H compressors have a wide operating envelope. All the operating conditions tested in Enea are well inside the envelope.

Some of tested points in Enea

Heat pump at case study 4

Mauro Dallai Milano – 16th March 2016 6

è  The widest CO2 compressor range available in the market

è  Design pressure: LP side 100 bar, HP side 150 bar

è  Displacements @ 50 Hz from 1.1 m3/h to 26.5 m3/h

è  Heating capacity (T_air=7°C; Tin_w=10°C) from 6 kW to 140 kW

CD-H compressor range

Range Cylinder Displacement @ 50Hz

Heating capacity

[m3/h] [kW]

CD200 2 1,12 ÷ 3,00 6 ÷ 16

CD300 2 4,34 ÷ 11,62 23 ÷ 65

CD400 4 9,48 ÷ 26,57 50 ÷ 140

Mauro Dallai Milano – 16th March 2016 7

2016 INCOMING LARGER RANGE

NEW RANGE CD500

•  6 cylinders compressor •  Displacement from 39,8 to 59,5 m3/h •  Nominal power from 50 to 80 HP •  Heating capacity (T_air=7°C; Tin_w=10°C up to 250 kW) •  External discharge manifold (oil temperature reduction, compressor efficiency increase) •  Design pressure: 100 bar (LP) e 150 bar (HP) •  Safety valve on both low and high pressure sides

Mauro Dallai Milano – 16th March 2016 8

Dorin Software now available in our website for easy compressor selection

Mauro Dallai Milano – 16th March 2016 9

Heat pump at case study 5

Case Fluid Source Tamb(ºC) Sink T(ºC) Application (kW)

1 HC (Propane) Air

-10 to 35

(outdoor air) Water

40 to 50 Heating water production 40

60 Low demand of Domestic hot water

2 HC (Propane)

Water (brine) -5 to15 Water

40 to 50 Heating water Production

60 60 Low demand

of Domestic hot water

3 HC (Propane)

Water (Neutral

loop)

10 to 15 (Sewage water) or 25 to 30

(Condensation loop)

Water 60 Domestic hot water production 50

4 CO2 Air -10 to 10 (winter)

20 to 35 (summer) (outdoor air)

Water 60 to 80 Domestic hot water production 30

5 CO2 Air -10 to 35 (outdoor air) Water

80 (return water

40)

Heating & domestic hot water production 50

Mauro Dallai Milano – 16th March 2016 10

Heat pump at case study 5

Two stage compression economized transcritical cycle

Main and auxiliary compression realized in a single prototype compressor

Main compression stage

Auxiliary compression stage

Mauro Dallai Milano – 16th March 2016 11

Heat pump at case study 5

Prototype compressor CDHP2500 derived from 4 cylinders CD compressor

3 cylinders for main compression stage and 1 cylinder for auxiliary stage

Mauro Dallai Milano – 16th March 2016 12

Heat pump at case study 5

Main characteristics are:

•  two stage transcritical compressor •  4-cylinders bore 34 mm stroke 37 mm •  swept volume 8,76 + 2,92 m3/h at 50 Hz (main + auxiliary stage) •  volume ratio 3 to 1 •  motor 380-420V/3/50Hz PWS •  max operating current 45 A •  design pressure: LP 100 bar

HP 150 bar

Installed compressor: special model CDHP2500

Mauro Dallai Milano – 16th March 2016 13

Heat pump at case study 5

Compressor CDHP2500 : arrangement of main and auxiliary suction ports

Mauro Dallai Milano – 16th March 2016 14

Heat pump at case study 5

Compressor CDHP design: external and large volume common discharge manifold

Suction side Ambient air

Discharge side

ü  Lower discharge temperature

ü  Lower oil temperature

ü  Better lubrication

ü  Containment of pressure pulsations

è HIGHER RELIABILITY

è HIGHER EFFICIENCY

Reduced heat transmission rate from discharge to suction side

Mauro Dallai Milano – 16th March 2016 15

Isentropic  efficiency  of  CDHP  compressor

0

0,1

0,2

0,3

0,4

0,5

0,6

0,7

0,8

0 1 2 3 4 5 6

Volumetric  efficiency  of  CDHP  compressor:  for  both  stages

y  =  -­‐0,0856x  +  1,0398

R2  =  0,9528

00,10,20,30,40,50,60,70,80,91

0 1 2 3 4 5 6

Heat pump at case study 5

Compressor CDHP 2500: measured performance during experimental campaign

-  Volumetric efficiency similar to single stage compressor

- - Isoentropic efficiency smoothly lower than single stage compressor

Mauro Dallai Milano – 16th March 2016 16

•  8 compressor models derived from 4 cylinders CD range

•  Displacements at 50 Hz from 7.1 m3/h to 20 m3/h (main compression stage)

•  Motor nominal power from 15 HP to 50 HP

•  Volume ratio main / aux stage 3:1

•  Design pressure: LP side 100 bar, HP side 150 bar

•  Heating capacity (T_air=7°C; Tin_w=40°C Tout_w=80°C) from 40 kW to 110 kW

CD-HP future compressor range

Mauro Dallai Milano – 16th March 2016 17

THANK YOU FOR YOUR KIND ATTENTION