latest heat pump technologies in japanhpc2017.org/wp-content/uploads/2017/06/k471.pdfsince r32 has...

Waseda UniversityKiyoshi Saito

LATEST HEAT PUMP TECHNOLOGIES IN JAPAN

IEA Heat Pump Conference 2017Waseda University

2

INTRODUCTION

In Japan, since great effort to improve performance of heat pump system has beenmade, still new technologies appears. For example,

• Improve annual performance of heat pump• widen utilization range for example increasing supply temp• Improve comfortableness of air-conditioning system• adopt lower GWP refrigerant• develop simulation technologies to predict and compare performances of various

refrigerants

Today, I would like to introduce some interesting and representative heat pumptechnologies.


3

DOMESTIC HEAT PUMPIn Japan, sales of a CO2 heat-pump water heater began in 2001, and in the 15 years 5 million systems have already entered market in Japan.

Exceeded5millionunitsinMarch2016

Exceeded2millionunitsinOct.2009

Exceeded3millionunitsinAug.2011

Exceeded4millionunitsinOct.2013

(10-thousand units)

(Fiscal Year)

Feature of system is that system is combined with thermal storage tankis controlled optimally for life styleis very compact.


4

DOMESTIC HEAT PUMP WATER HEATERSo many new technologies have been developed for compressors and heat exchangers

スイングブッシュ

ピストンクランクシャフト

ベーン

ローラ一体化

スイングブッシュ

ピストンクランクシャフト

ベーン

ローラ一体化

可動スクロール

固定スクロール

接触点

A CB

CO2-水

熱交換器 2003年

モデル～

ﾒｰｶｰ

圧縮機

多くの

ﾒｰｶｰに

OEM

二段圧縮式

(中間圧

はｹｰｽ内に)

スイング式

(ｼｰﾙは面接触)ｽｸﾛｰﾙ式

(＋効率

向上に

ｴｼﾞｪｸﾀ)

初号機は

ｷｬﾋﾟﾗﾘｰﾁｭｰﾌﾞ

の束を水ﾁｬﾝｴﾙ

が囲む方式

水配管に

冷媒配管

を埋込み

水配管に冷媒配管を巻き付け

D

冷媒配管

水配管（ツイスト管）

ロータリー式CO2圧縮機

ﾎﾟｷﾎﾟｷ

ﾓｰﾀ

広げた鉄心にｺｲﾙを巻いてから丸める

（高密度で整列巻を容易に）


5

DOMESTIC HEAT PUMP WATER HEATERFor this development, ejector was developed. Ejector is used to be used instead of

expansion valve to enhance COP. Recently, ejector was used to realize a double-stage evaporator. This decreases defrost time and consequently increases systemperformance.

Higher temp.Lower temp.

Fin

Frost

Tube


6

AIR-CONDITIONER

Most manufacturers already adopted R32for room and package-type air-conditioners.Since R32 has flammability, a risk assessmentwas already performed by Japan Society ofRefrigeration and Air-conditioning Engineers(JSRAE), and a safety standard was established.

Manufacturers that use R32 as refrigerant

Room Type Package Type

1. Daikin

2. Hitachi

3. Mitsubishi

4. Panasonic

5. Sharp

6. Fujitsu General

7. Toshiba Carrier

8. Other【Corona】

1. Daikin

2. Mitsubishi

3. Toshiba Carrier

4. Panasonic

5. Other


7

AIR-CONDITIONERTo make system compact and reduce refrigerant charge, heat exchanger that adopt

multi-hole flat tubes have been developed for outdoor unit of package air-conditioner. For some system, 30% Weight reduction, 20 % Volume reduction, 13%refrigerant charge reduction


8

AIR-CONDITIONER4-stage compressor has been developed to further improve cycle performance

when using CO2 as refrigerant. About 20% COP improvement can be realized.


9

AIR-CONDITIONEROccupant detector has been developed.Left system can supply air at two

different temperatures for two separateoccupants.

Right system can find out best way tosupply air from image sensor analysis.Using this, 24% energy saving can berealized.

"Air-Flow-Paths" OFF ON

Foot Temperature 24.1℃ 24.2℃

Setting Temperature 26.5℃ 23.0℃

Electric Energyper one hour 790Wh 597Wh

Effect of Power Saving 24.4%

-3.5℃

"Air-Flow-Paths" OFF "Air-Flow-Paths" ON

Air ConditioningArea

Air ConditioningArea


10

GAS ENGINE HEAT PUMP

ExpansionValve

Condenser

Evaporator

Compressor

Gas Engine

Waste heat

City gas

0

2

4

6

8

10

12

14

110％ 100％ 90％ 80％ 70％

エンジン回転数：定格

エンジン回転数：最大

Sub-

cool

of re

frig

eran

t [℃

]

Refrigerant charge

Gas engine driven heat pump (GHP) is widely used in Japan. Latest system can supply electricity when electric supply stops. New refrigerant leak detect method is developed. This system can be driven only by stable waste heat of gas engine without any load. From this stable driving, refrigerant leak can be easily detected.


11

HEAT PUMP STEAM GENERATOR

0 200 400 600 800 1000102

103

104

SpecificenthalpykJ/kg

PressurekPa

180

T=4

0o C

BUTANE

60 80 100

120

140

160

200

膨張弁開度 100 パルス 110 パルス 120 パルス 130 パルス 140 パルス 150 パルス

A very compact 120 oC steam generator heat pump system with a heat capacity ofapproximately 30 kW was developed. We are developing a 165 oC steamgenerating heat pump system For this system, we optimized cycle and componentsusing a theoretical analysis and experiment.


12

CENTRIFUGAL CHILLER

12

冷却除湿

A centrifugal chiller whose refrigerant is H2O was developed. Hybrid system thatconsists of this chiller and a desiccant dehumidification system is developed forsubway station. 40% performance improvement will be expected.


13

ABSORPTION TECHNOLOGIES

SE/DL cycle has been developed. This cycle can be driven by wider glide of heat sources. This system can use lower grade heat sources.


14

ABSORPTION TECHNOLOGIES

0 20 40 60 80 100 120 140 160 180 2000

20

40

60

80

100

120

1400% 40% 50% 60%

70%

Solution temperature TS oC

Refri

gera

nt te

mpe

ratu

re T

R o C

Factories normally use an 8 kgf/cm2 steam pipingnetwork to supply steam at a temperature ofapproximately 180 oC.

To realize 180 oC steam generation, we developeddouble-lift and triple-stage absorption heattransformers. 180 oC steam generation from 88 oCwas realized with practical system.


15

SIMULATION TECHNOLOGIES

Evaporator

Compressor

Accumulator

Condenser

ExpansionValve

ReversingValve

Indoor Fan

Outdoor Fan

Expansion valve

Compressor

Accumulator

Condenser

Evaporator

Expansionvalve

Heat exchanger Expansionvalve

04080120

Rot

atio

nal

spee

dn C

OM

01 rp

s

0200400600

Val

ve1

open

ing

puls

e0

200400600

Val

ve2

open

ing

puls

e

0200400600

Val

ve3

open

ing

puls

e

0200400600

Val

ve4

open

ing

puls

e

0

5

10

Coo

ling

capa

city

QEV

A1 k

W

0

5

10

Coo

ling

capa

city

QEV

A2 k

W

0

5

10

Coo

ling

capa

city

QEV

A3 k

W

0

5

10

Coo

ling

capa

city

QEV

A4 k

W

02468

Com

pres

sor

inpu

tkW

0102030

Coo

ling

capa

city

kW

-200 0 200 400 600 800 10000

5

10

CO

PTime t s

2000

2500

3000

Pres

sure

P CO

M O

kPa

-200 0 200 400 600 800 1000500

1000

1500

Time t s

Pres

sure

P CO

M I k

Pa

“Energy flow +M” is a general purpose energy system analysis simulator wedeveloped. Steady and unsteady calc. of almost every type of heat pump –compression, absorption, adsorption can be realized.

Japan refrigeration and air conditioning industrial association (JRAIA) adoptour simulator as common calculation tool to predict the cycle performance of heatpump with various refrigerants.


1616

SIMULATOR “ENERGY FLOW+M”

Exp.

Cond.

Accum.

Comp.

Eva.

Controller


17

DYNAMICS OF VRF

17

Expansion valve

Compressor

Accumulator

Condenser

Evaporator

Expansionvalve

Heat exchanger Expansionvalve

04080120

Rot

atio

nal

spee

dn C

OM

01 rp

s

0200400600

Val

ve1

open

ing

puls

e0

200400600

Val

ve2

open

ing

puls

e

0200400600

Val

ve3

open

ing

puls

e

0200400600

Val

ve4

open

ing

puls

e

0

5

10

Coo

ling

capa

city

QEV

A1 k

W

0

5

10

Coo

ling

capa

city

QEV

A2 k

W

0

5

10

Coo

ling

capa

city

QEV

A3 k

W

0

5

10

Coo

ling

capa

city

QEV

A4 k

W

02468

Com

pres

sor

inpu

tkW

0102030

Coo

ling

capa

city

kW

-200 0 200 400 600 800 10000

5

10

CO

P

Time t s

2000

2500

3000

Pres

sure

P CO

M O

kPa

-200 0 200 400 600 800 1000500

1000

1500

Time t s

Pres

sure

P CO

M I

kPa

Fig. Dynamics of VRF

Dynamic interaction of VRF system can be calculated


18

GHP CALCULATION

18

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Coolingcapacity-

Outdoorfanrotationalspeed-0.4 0.6 0.8 1 1.20.2

0.40.60.81

1.21.4

Pressure

P COMOkPa

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Electricinpu

t-

Outdoorfanrotationalspeed%

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Pressure

P COMIkPa

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Gasinp

ut-

Outdoorfanrotationalspeed-

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COP

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COPg


0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COPp


0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Coolingcapacity-

Outdoorfanrotationalspeed-0.4 0.6 0.8 1 1.20.2

0.40.60.81

1.21.4

Pressure

P COMOkPa

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Electricinpu

t-Outdoorfanrotationalspeed%

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Pressure

P COMIkPa

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Gasinpu

t-


0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COP

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COPg


0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COPp


0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Coolingcapacity-

Outdoorfanrotationalspeed- 0.4 0.6 0.8 1 1.22000

2500

3000

3500

4000

Pressure

P COMOkPa

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Electricinpu

t-


0.4 0.6 0.8 1 1.20

500

1000

1500

2000

Pressure

P COMIkPa

Outdoorfanrotationalspeed-0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

Gasinpu

t-


0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COP

0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COPg


0.4 0.6 0.8 1 1.20.20.40.60.81

1.21.4

COPp


Fig. Performance calc. of Gas engine heat pump


19

MULTI PHYISICS SIMULATION

19

0

10

20

30

40

50

60

22

23

24

25

26

27

28

-10 0 10 20 30 40 50 60 70 80 90 100 110 120

圧縮機回転数rps

室内温度℃

時間 m in

室内温度

制御出力（圧縮機回転数）

室内温度設定値

室内温度平均

400

800

1600

3200

6400

150 200 250 300 350 400 450 500

圧力

kP

a

比エンタルピ kJ/k g

R410A

室内温度設定 26℃, 冷媒流量 0.109 k g/s

室内温度設定 24℃, 冷媒流量 0.073 k g/s

側面図(B-B’面)_温度分布

A A’

・27.4℃

・22.4℃

・24.6℃

Sensor : 26.1℃

・23.0℃・23.5℃

℃

26℃設定定常時上面図(A-A’面）_温度分布B B’

・26.7℃

・26.1℃

・24.4℃

・25.2℃

・24.5℃

・23.7℃

・24.2℃

・23.6℃

・22.4℃・22.7℃

側面図(B-B’面）_気流分布m/ s

・0.04m/s ・0.08m/s

・0.27m/s

・0.27m/s

・0.16m/s

・0.18m/s

・0.06m/s

・0.17m/s

・0.29m/s・0.11m/s

部屋室内機

室外機

Heat pump cycle Indoor temp. control Super-heat control

Temperature and humidity distribution

30

40

50

60

70

80

90

100

0

2

4

6

8

10

12

14

-10 0 10 20 30 40 50 60 70 80 90 100 110 120

膨張弁開度pulse

過熱度℃

時間 m in

過熱度制御出力（膨張弁開度）

過熱度設定値


20

SIMULATION TECHNOLOGIES

0 1 2 30

0.3

0.6

0.9

1.2

1.5

Elec

tric

inpu

t E k

W

R 410A(Rated cooling) HC 600a(Rated cooling) R 410A HC 600a

0

20

40

60

80

100

PressureP* %

Distance-

COM

inlet

COM

out

let

CON

inlet

CON

out

let

EXP

inlet

EXP

outle

t

EVA

inlet

EVA

out

let

COM

inlet

R-410A(n=100%) R-410A(50%) HC-600a(100%) HC-600a(50%)

0 1 2 30

2

4

6

8

COP

-

0 1 2 30

50

100

150

200

Pres

sure

dro

p ΔP E

VA

kPa

Cooling capacity Q kW

R410A R600a

Theoretical analysis R410A R600a

Evaporation temperature,℃ 10.0

Condensation temperature,℃ 45.0

Sub cooled temperature,℃ 5.0

Super heat temperature,℃ 5.0

Adiabatic efficiency,- 1.0

Theoretical COP,- 6.40 7.13

Compressor inlet specific volume, m3/kg

0.0248 0.174

Evaporator specific enthalpy difference, kJ/kg

164 280

Refrigerant flow rate per unit of cooling capacity, kg/(s･kW)

0.00610 0.00357

R600a drop-in calc. and experiment are carried out. Result show that under ratedconditions, electricity consumption was greatly decreased, but cooling capacity wasalso decreased. Enery saving can’t be realized only by drop-in.


21

CONCLUDING REMARKSI introduced the latest heat pump technologies in Japan. The progress of these heat

pump technologies is very slow compared to computer, electrical and electronictechnologies.

I think that this slow progress continues. However, we need to steadily improvetechnologies of heat pumps for new applications, ZEB, smart grid and so on.

We will do our best to spread heat pump technologies throughout the world.

Moving air-conditioner

latest heat pump technologies in japanhpc2017.org/wp-content/uploads/2017/06/k471.pdfsince r32 has...

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