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| Thread ID: 111082 | 2010-07-13 03:20:00 | Anybody experienced flash-freezing of windsceen ice? | Billy T (70) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 1118422 | 2010-07-13 03:20:00 | Short story: Daughter was house sitting in a low-lying property (just above sea level) on Auckland Harbour. We had a very severe frost on Saturday night and just after 6:00am Sunday she went out to load the car to go off to work and it was really iced up. She washed all the frost off with water then found she'd locked her keys in the boot so rang me to bring the spares. I dropped them off 15 minutes later, checked that she was still frost free on the front & rear screens etc, backed out the drive, waited until she started backing out then took off, duty done. I got about a km down the road and her lights hadn't appeared so I went back and found that she'd had a slow speed impact with a parked car about 100 metres from the driveway. She said that as she drove down a dip in the road the windscreen suddenly went opaque, she thought it was mist and tried the wipers & washer, then stopped but not quite fast enough. I checked and found that the screen was completely opaque with a thin layer of ice, and some lumpy bits where the window-washer water had frozen, and I had to shave it off with the edge of a credit card. We left a note on the car she hit as we couldn't see which house it belonged to, and random door knocking before 6:30am didn't seem to be a good idea. Insurance will take care of it OK, and the owner of the car she hit was more concerned that she was not hurt than anything else, but I've never seen anything like that before in my life. Here (www.c00lstuff.com) is a video of a similar effect, but has anybody ever seen a wet screen go to ice in a flash? I guess the air in the dip was few degrees colder and all the cars around were really frosted up, but from full vision to zero in a blink of an eye??? This kind of effect doesn't happpen too often in Auckland, in fact where we live we don't get frosts at all. Cheers Billy 8-{0 |
Billy T (70) | ||
| 1118423 | 2010-07-13 03:28:00 | Got called out to fix a Vector truck replacing a power pole. 2am Sunday morning at Swanson( drunk woman driver hit power pole). It was blardy freezing and I am from the mountains in North West Nelson. I threw warm water on the windscreen when I left and it froze up 10 minutes later had to drive with my head out of the window until the windscreen washer and wipers cleared a bit on the windscreen. By the time I had finished 2 hours later my hands were numb. I dont ever want to hear about the fraud called global warming ever again. |
prefect (6291) | ||
| 1118424 | 2010-07-13 03:49:00 | Haven't experienced that Billy, but some of my cycling mates and I went down to Waitakaruru on Sunday morning to do a 115km loop through Ngatea and Paeroa and back to Kopu - drove through patches of fog coming through Maramarua and found we had to scrape ice off the bike seats and handlebars before the ride. My feet have never been so cold - couldn't feel them after 10km and until we were back in the car heading home with the heater on full. Apparently a -4 low in the Waikato on Saturday night - hadn't warmed up by 8am either, then add windchill into the mix... I was even tempted to do the cowpat warm-up routine when we came across a herd being moved - but instead rode through it. Got splattered and had to spend nearly an hour after I got home cleaning the cowsh off the bike. On another occasion out Helensville way (about this time of the year), we had the fog freeze onto our sleeves and leggings while riding... I keep telling myself I enjoy cycling..... :D |
johcar (6283) | ||
| 1118425 | 2010-07-13 04:39:00 | We get that in Napier on the frost days. We have some beauts at times. I usually start up my van and run it for 5 minutes while I put lukewarm water on the windows with the wipers going and the heater on defrost. Any other way and you get iced up again pretty darned quick. Ken |
kenj (9738) | ||
| 1118426 | 2010-07-13 04:45:00 | You should leave the engine running for a couple of minutes with the windscreen demister on. The warm air on the inside of the windscreen will warm up the windscreen sufficiently to melt the frost on it. :) |
Trev (427) | ||
| 1118427 | 2010-07-13 04:50:00 | I think it could be due to latent heat effect (sorry thinking as a physical chemist when I studied at Uni). I use to see mist/thin ice materialize on the outside of pressure sealed flasks/tubes in lab experiments, due to difference (dunno if result of heat, pressure, dew point reached, or temperature gradient) between the inner and outer glass surfaces. | kahawai chaser (3545) | ||
| 1118428 | 2010-07-13 05:18:00 | This sort of happened to me on the way home from Chch on Sunday night, coming through Gowan Valley. There was a slight mist that was settling on the windscreen, I went to wash the windscreen and one of the jets was frozen, the other sprayed a bit and it immediately froze on the windscreen, I was pleased it was the drivers side jet that froze up so I could still see OK. I always make sure the windscreen is dry before driving away, around here any water just re-freezes as soon as there is any wind chill going on. |
wratterus (105) | ||
| 1118429 | 2010-07-13 05:22:00 | Thanks for the input, on reflection I recall reading some long time back of a demonstration somewhere in which water turned to solid ice when the container was tapped. It was definitely a 'shock freezing' effect. I'm trying to get my head around the science in case the Insurance Company suggests that we are telling porkies, though I saw the clear windows with my own two eyes, depite being hauled out of bed at such an ungodly hour of a Sunday morning. Not to mention that my daughter is no idiot or airheaded female. Cheers Billy 8-{) |
Billy T (70) | ||
| 1118430 | 2010-07-13 05:24:00 | Daughter was house sitting in a low-lying property (just above sea level) on Auckland Harbour . We had a very severe frost on Saturday night . . . . . She washed all the frost off with water . . the windscreen suddenly went opaque, Not to be rude but Auckland doesn't have severe frosts . -13 like in Arrowtown the other night is a severe frost . And yep, I've had that . Often . Down there . Rule 1: After rinsing windscreen, wipe it with a towel or something to remove water . Down South it will freeze back instantly . Wipers aren't any use - they become glued to the windscreen . |
pctek (84) | ||
| 1118431 | 2010-07-13 05:36:00 | Thanks for the input, on reflection I recall reading some long time back of a demonstration somewhere in which water turned to solid ice when the container was tapped . It was definitely a 'shock freezing' effect . I'm trying to get my head around the science in case the Insurance Company suggests that we are telling porkies, though I saw the clear windows with my own two eyes, depite being hauled out of bed at such an ungodly hour of a Sunday morning . Not to mention that my daughter is no idiot or airheaded female . Cheers Billy 8-{) Supercooling, a classical physics demonstration: . youtube . com/watch?v=fSPzMva9_CE" target="_blank">www . youtube . com . metacafe . com/watch/750810/supercooled_water_nucleation_experiments/" target="_blank">www . metacafe . com Instant misting up can occur on a cold morning when driving from colder into warmer air, often when going up a hill, this is also disconcerting |
Terry Porritt (14) | ||
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