Supercooling and freezing dirty water:

Transcription

1 Supercooling and freezing dirty water: A laboratory investigation of thermally observable phenomena associated with cooling and freezing James D. Brownridge Department of Physics, Applied Physics, and Astronomy, Binghamton University, Binghamton, New York jdbjdb@binghamton.edu Physics, Chemistry and Biology of Water Bulgaria, October, 2013

2 If there is magic on this planet, it is contained in water. (Loren Eiseley, The Immense Journey, 1957)

3 I will start by showing magic that you may not have seen

4 Upside down convection Heat in ~700mW Temp. at bottom of tube (outside) Heat out

5 Upside down convection ON/OFF 40 o C -10 o C

6 A world record? This vial was held at -15 o C for 422 days Checked >1 yr later and it still cooled to below -15 o C

7 YES Muddy pothole water will supercool Typical cooling curve

8 As will all of these: Coffee -5.9 o C Apple cider -5.3 o C Milk -6.5 o C Muddy water Orange juice -2.9 o C -7.8 o C Grasses in water Tea -6.7 o C Dirty water -4.3 o C -5.1 o C -7.1 o C -4.5 o C

9 Magic Divide - and each vial will release latent heat at a different temperature Time to freeze for a typical vial and supercooling temperature For 138 cycles ± 0.2 o C -

10 LN 2 The perfect ice nucleator Ice crystal Onset of freezing at 0 o C Onset of freezing at 0 o C and -5 o C Supercooling 0n/Off on demand

11 Water escaping from a plastic water bottle Polyethylene Terephthalate (PETE) New After 3 years H 2 O Out

12 What happens when clean and dirty water begins freezing?

13 B 1 cc Water 0.5 cc of water A 51 K v uf 0.5M TC emf 51 K v uf 0.5M Start of freezing End of freezing

14 Voltage (mv) Temperature Temperature ( o C) Time (sec)

15 An example of dirty water freezing and thawing

16 *

17 Temperature Freezing water in a large container Freezing supercool water Time (X 0.1 sec Water clusters?

18 End of show and tell Now Magic in Detail Effect of: Cooling from below

19 Heating water from below Rayleigh Bénard convection is a type of natural convection, occurring in a plane of fluid heated from below, in which the fluid develops a regular pattern of convection cells known as Bénard cells. Studied for > 100 yrs. This is a file from the Wikimedia Commons.

20 Mosaic Structures and Circulation From G. Pollack s The Fourth Phase of Water

21 Upside down convection Warm Thermocouples Up Down G. Pollack Cold ~-8 o C Bottom of water column supercooled.

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23 Stable vertical convection cells with respect to gravity

24 Tilt Then back Bath temperature

25 Notice that the vertical ΔT around TC 6 is << than the horizon ΔT 1cm 6 1 Horizon ΔT = 2cm Vertical ΔT < ~0.5 o C

26 Now we induce thermal oscillations By adding D 2 O Clusters Freq. decreasing D 2 O Take a closer look

27 Thermal oscillations

28 D 2 O to H 2 O The effect

29 Look here 10ml

30 Smoothed by adjacent averaging

31 Thermal oscillation frequency vs. time

32 Buoyancy Buoyancy Density Density

33 No gradients ~20 o C Density decreasing from 1 to.9 Density Maximum = 1 Density Decreasing from 1 to.9 ~20 o C Now we have a density and thermal gradient ρ ~-8 o C >4 o C ~4 o C <4 o C

34 ..... Heat out TC >4 o C <4 o C

35 H 2 O water clusters only H 2 O + D 2 O water clusters 0% 12.5% 25% 50%

36 Metastable motion in a column of water cooled from the bottom Heat Heat 20 o C ρ = kg/m 3 Temperature ΔT = 0 D 2 O Clusters H 2 O Clusters D 2 O Clusters Temperature ΔT = 2 o C D 2 O Clusters Metastable Thermal and Density Gradients H 2 O Clusters At 3.98 o C ρ =1000 kg/m 3 Temperature ΔT = 0 Heat Heat -8 o C ρ = kg/m 3

37 Day Night Surface ΔT 6 o C Sunrise Water temperature on a mostly sunny day Bottom mud 24 hrs. in the life of a pond 2013 J. D. Brownridge

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39 Metastable Thermal and Density Gradients Now ~No Thermal or Density Gradients

40 Water clusters From G. H. Pollack The Fourth Phase of Water

41 Making D 2 O water clusters in H 2 O water

42 Experimental setup to measure the effect of D 2 O clusters 7 Thermocouple(s) Heat flow Time from a to b? a b 110 ml Water bottle Ice bath

43 Time for heat to flow from center to outside wall The 60sec time delay is a clear effect of D 2 O water clusters in water 60 sec delay Due to D 2 O clusters

44 6 TCs Thermocouple(s) 110 ml Water bottle Ice bath No phonon scattering Phonon scattering Note The effect of no clusters vs. clusters Note

45 Effect of D 2 O water clusters on cooling curves TC TC TC TC TC TC Not stirred D 2 O clusters broken apart

46 Thank you

47 Day Night Surface ΔT 6 o C Sunrise Water temperature on a mostly sunny day Bottom mud 24 hrs. in the life of a pond 2013 J. D. Brownridge

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