Viscosity of Automotive Antifreeze

Cartechnic CT12 plus / pure
Cartechnic CT12 plus / diluted
VW G13 / pure
VW G13 / diluted

Description

Pure Substance

Automotive antifreeze, also called coolant, is the liquid which is used in the radiator and cooling system of an internal combustion engine for vehicles.

The main ingredient in most coolants is ethylene glycol or propylene glycol. Automotive antifreeze keeps the cooling water from freezing in winter and from boiling in summer. A further task is to lubricate the cooling system, such as the water pump. Most antifreezes contain corrosion inhibitors and other additives, like foam depressants.

Diluted Substance

Besides its use in radiator systems, automotive antifreeze mixed with water is also a heat transfer liquid for cooling thermostats or circulators used in labs.

Common mixtures are 50:50 or 40:60 of antifreeze : water. Other mixtures are 30:70 or 20:80 of antifreeze : water (% by volume). Mixtures with lower antifreeze content have also lower viscosity, which leads to less flow resistance and less load of the thermostat's pump.

Such liquids can be used for flow temperatures down to -25°C, depending on the application the thermostat is used for. Below this temperature the flow resistance due to increasing viscosity (and possibly long hoses with quick connectors) is too high for proper cooling performance.

Viscosity Tables – Measurement data

Table CT12+ Pure

Temp. [°C] Dyn. Viscosity [mPa.s] Kin. Viscosity [mm²/s] Density [g/cm³]
20 31.72 28.12 1.1282
15 40.86 36.11 1.1316
10 53.59 47.22 1.135
5 71.72 63.01 1.1383
0 98.15 85.98 1.1416
-5 137.63 120.22 1.1448
-10 198.25 172.68 1.1481
-15 294.07 255.4 1.1514
-20 450.54 390.18 1.1547
-25 715.28 617.58 1.1582
-30 1181.23 1016.9 1.1616
-35 2036.19 1747.8 1.165
-40 3662.42 3135.1 1.1682

CT12+ Automotive Antifreeze pure - kinematic viscosity and density over temperature

Table VW G13 Pure

Temp. [°C] dyn. viscosity [mPa.s] kin. viscosity [mm²/s] Density [g/cm³]
20 45.37 39.72 1.1421
15 59.80 52.21 1.1455
10 80.03 69.66 1.1488
5 109.42 94.98 1.1521
0 153.14 132.55 1.1553
-5 220.00 189.89 1.1586
-10 325.09 279.80 1.1619
-15 495.44 425.19 1.1652
-20 780.88 668.19 1.1686
-25 1276.40 1089.20 1.1720
-30 2166.70 1843.70 1.1752
-35 3841.20 3259.50 1.1784
-40 7138.30 6040.80 1.1817
-45 13914.00 11743.00 1.1848

VW G13 Automotive Antifreeze pure - kinematic viscosity and density over temperature

 

Table VW G13 | Diluted 60 : 40 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 63.15 % by vol]

Temp. [°C] dyn. viscosity [mPa.s] kin. viscosity [mm²/s] Density [g/cm³]
20 6.34 5.8 1.0935
15 7.75 7.06 1.0964
10 9.53 8.67 1.0992
5 11.91 10.81 1.1019
0 15.14 13.71 1.1046
-5 19.64 17.73 1.1073
-10 26.04 23.46 1.1099
-15 35.43 31.85 1.1125
-20 49.65 44.53 1.115
-25 71.79 64.24 1.1174
-30 107.48 95.97 1.1199
-35 167.29 149.07 1.1222
-40 271.31 241.24 1.1247
-45 459.01 407.24 1.1271
-50 813.83 720.44 1.1296

VW G13 diluted 60:40 with water (% by volume) - kinematic viscosity and density over temperature

 

Table CT12+ | Diluted 50 : 50 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 51.8 % by vol]

Temp. [°C] Dyn. Viscosity [mPa.s] Kin. Viscosity [mm²/s] Density [g/cm³]
20 3.98 3.72 1.0695
15 4.72 4.4 1.0721
10 5.69 5.29 1.0744
5 6.96 6.46 1.0777
0 8.66 8.02 1.0800
-5 10.98 10.15 1.0822
-10 14.23 13.13 1.0842
-15 18.91 17.4 1.0863
-20 25.83 23.74 1.0883
-25 36.34 33.33 1.0903
-30 52.96 48.49 1.0921
-35 80.24 73.35 1.0939
-40 126.95 115.86 1.0957

CT12+ diluted 50:50 with water (% by volume) - kinematic viscosity and density over temperature

 

Table VW G13 | Diluted 50 : 50 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 51.48 % by vol]

Temp. [°C] dyn. viscosity [mPa.s] kin. viscosity [mm²/s] Density [g/cm³]
20 4.29 3.98 1.0771
15 5.14 4.76 1.0797
10 6.22 5.75 1.0824
5 7.64 7.04 1.0849
0 9.53 8.77 1.0873
-5 12.14 11.14 1.0897
-10 15.80 14.47 1.0919
-15 21.08 19.27 1.0941
-20 28.90 26.37 1.0962
-25 40.91 37.25 1.0982
-30 59.89 54.44 1.1001
-35 91.03 82.60 1.1020

VW G13 Automotive Antifreeze diluted 50:50 with water (% by volume) - kinematic viscosity and density over temperature

 

Table CT12+ Diluted | 40 : 60 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 45.41 % by vol]

Temp. [°C] Dyn. Viscosity [mPa.s] Kin. Viscosity [mm²/s] Density [g/cm³]
20 3.32 3.13 1.0612
15 3.95 3.71 1.0635
10 4.71 4.42 1.0659
5 5.72 5.35 1.0681
0 7.05 6.59 1.0702
-5 8.88 8.28 1.0722
-10 11.42 10.63 1.0741
-15 15.06 14.00 1.0759
-20 20.44 18.96 1.0776
-25 28.51 26.42 1.0793

CT12+ diluted 40:60 with water (% by volume) - kinematic viscosity and density over temperature

 

Table VW G13 Diluted | 40 : 60 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 39.07 % by vol]

Temp. [°C] dyn. viscosity [mPa.s] kin. viscosity [mm²/s] Density [g/cm³]
20 3.01 2.84 1.0591
15 3.54 3.34 1.0614
10 4.22 3.96 1.0636
5 5.09 4.78 1.0656
0 6.26 5.86 1.0676
-5 7.85 7.34 1.0694
-10 10.04 9.38 1.0710
-15 13.18 12.29 1.0726
-20 17.76 16.53 1.0740

VW G13 diluted 40:60 with water (% by volume) - kinematic viscosity and density over temperature

 

Table CT12+ Diluted | 30 : 70 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 34.42 % by vol]

Temp. [°C] Dyn. Viscosity [mPa.s] Kin. Viscosity [mm²/s] Density [g/cm³]
20 2.49 2.38 1.0466
15 2.92 2.79 1.0484
10 3.45 3.29 1.0504
5 4.15 3.94 1.0521
0 5.07 4.81 1.0537
-5 6.31 5.97 1.0568
-10 8.05 7.61 1.0574
-15 10.51 9.93 1.0584
-20 14.13 13.34 1.059

CT12+ diluted 30:70 with water (% by volume) - kinematic viscosity and density over temperature

 

Table VW G13 Diluted | 30 : 70 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 29.64 % by vol]

Temp. [°C] dyn. viscosity [mPa.s] kin. viscosity [mm²/s] Density [g/cm³]
20 2.34 2.24 1.0450
15 2.70 2.58 1.0470
10 3.18 3.04 1.0488
5 3.81 3.63 1.0505
0 4.63 4.41 1.0520
-5 5.75 5.46 1.0533
-10 7.28 6.90 1.0544
-15 9.45 8.95 1.0553

VW G13 diluted 30:70 with water (% by volume) - kinematic viscosity and density over temperature

 

Table CT12+ Diluted | 20 : 80 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 23.21 % by vol]

Temp. [°C] Dyn. Viscosity [mPa.s] Kin. Viscosity [mm²/s] Density [g/cm³]
20 1.86 1.80 1.0313
15 2.16 2.09 1.0327
10 2.53 2.45 1.0342
5 3.01 2.91 1.0355
0 3.65 3.52 1.0366
-5 4.50 4.34 1.0374
-10 5.67 5.46 1.0381

CT12+ diluted 20:80 with water (% by volume) - kinematic viscosity and density over temperature

 

Table VW G13 Diluted | 20 : 80 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 19.10 % by vol]

Temp. [°C] dyn. viscosity [mPa.s] kin. viscosity [mm²/s] Density [g/cm³]
20 1.76 1.71 1.0288
15 2.01 1.95 1.0305
10 2.34 2.27 1.0319
5 2.76 2.67 1.0331
0 3.32 3.21 1.034
-5 4.07 3.93 1.0347
-10 5.09 4.92 1.0351

VW G13 diluted 20:80 with water (% by volume) - kinematic viscosity and density over temperature

 

Table VW G13 Diluted | 10 : 90 Antifreeze : Water (% by vol)

[exact content of antifreeze, considering volume contraction: 12.74 % by vol]

Temp. [°C] dyn. viscosity [mPa.s] kin. viscosity [mm²/s] Density [g/cm³]
20 1.53 1.50 1.0188
15 1.72 1.69 1.0202
10 1.97 1.93 1.0213
5 2.29 2.24 1.0222
0 2.72 2.66 1.0228
-5 3.31 3.23 1.0230

VW G13 diluted 10:90 with water (% by volume) - kinematic viscosity and density over temperature

 

Volume Contraction for Diluted Substance Antifreeze : Water

Due to volume contraction, the nominal relation values for the mixtures in % by volume are not exact in the above tables. Volume contraction in chemistry means that if mixing two different liquids the total volume is less than the sum of the single components' volumes. For example, if adding 100 mL of water to 100 mL of ethanol, the resulting volume is less than 200 mL. How strong this effect is depends on the components, but it is considerable if mixing water and alcohol.

The exact content of antifreeze in the tested mixtures in % by volume is given in brackets [ ].

See also the charts that show viscosity and density over exact concentration for several temperatures and both substances, CT12+ and VW G13.

CT12+ and VW G13 diluted with water - kinematic viscosity over concentration (% by volume) at several temperatures

 

CT12+ and VW G13 diluted with water - density over concentration (% by volume) at several temperatures

 

Reference

Measured with SVM™.

Metainformation

Reference Measurement with SVM™
Kin. vis. yes
Dyn. vis. yes
Density yes
Multiple temperatures yes
Related Glycol, antifreeze, coolant, heat transfer liquid