Adventures with dipstick warmer - Page 3 - PeachParts Mercedes-Benz Forum

strelnik · #31 02-20-2015, 09:45 AM

Quote:

Originally Posted by bricktron

i'm not so sure this is true. oil and steel conduct heat just fine, and a heating element surrounded by a giant heat sink will give up that energy nearly as fast as it comes in. i think the heating element surface will get way hotter in free air than inside the oil sump. compare a flame on your stovetop, which will make red-hot a little piece of wire, but no part of a cast-iron pan.

nonetheless, i'm not a physicist or a chemical engineer!

Brickton,
Thanks for being the first to admnit that you don't know the answer.

Now you see why I've set aside 6 quarts of dirty diesel oil that I'm putting into a spare container so I can try this experiment using a non contact thermometer on the black surface.

Details to follow.

strelnik · #32 02-20-2015, 09:47 AM

Quote:

Originally Posted by moon161

'Adventures with dipstick heater' It sounds NC17 ;-)

.

Should we ask Aklim for nominees for the starring and supporting roles?
:-)

funola · #33 02-20-2015, 10:12 AM

Quote:

Originally Posted by bricktron

i'm not so sure this is true. oil and steel conduct heat just fine, and a heating element surrounded by a giant heat sink will give up that energy nearly as fast as it comes in. i think the heating element surface will get way hotter in free air than inside the oil sump. compare a flame on your stovetop, which will make red-hot a little piece of wire, but no part of a cast-iron pan.

nonetheless, i'm not a physicist or a chemical engineer!

Yes the surrounding oil will act as a giant heat sink and remove the heat from the element. The concern is the oil film that is in contact with the element will be raised to whatever the surface temp of the element is at, which maybe too high for the oil and degrades it prematurely. The oil moves around from convection and with time, all of the oil in the sump eventually gets "burned". It is all about heat density, temperature per unit surface area.

If you pull out an immersion oil heater and find carbon crust all over it, something is not right.

funola · #34 02-20-2015, 11:11 AM

Quote:

Originally Posted by Lucas

Ummm. Color temp has to do with the shade of the light in degrees kelvin. Completely different concept.

Second, We've all touched a hot light bulb, and still have our fingers. I've never checked the temp to be honest, but lots of things melt at those stated temps.

And thirdly, put a light bulb in a liquid and see how hot it gets, not air. Wait actually that's a bad idea. Lol.

But in all seriousness, this is a problem all the time in hydroponics and aquariums. And cycling it on and off is the answer.

You're right about color temp is in Kelvin. I thought the chart I posted was in F but if you convert 3,000 K to F, it is 4,940 F! That sounds high but there must be some relationship between color temp and actual temp.

The temp on the bulbs surface is much cooler than at the filament. I used to use a 1500 W hot water heater element (thermostatically controlled) submerged in a 55 gal barrel to heat veg oil to 100 F. Sure it could heat up that barrel much faster than 2 x 40 W incandescent bulbs which is what I am using now. The 80 W incandescent bulbs heats that 55 gal barrel up to 100 F just fine but it is not encrusted with carbon and is a not fire hazard like the hot water heater element.

Benzkid_300D · #35 02-20-2015, 12:34 PM

Quote:

Originally Posted by funola

You're right about color temp is in Kelvin. I thought the chart I posted was in F but if you convert 3,000 K to F, it is 4,940 F! That sounds high but there must be some relationship between color temp and actual temp.

From what I understand, the color temperature of a light has nothing to do with the actual surface temperature of a light. For example those LED lights have about 5,500K and are definitely cooler to touch than the typical 3,000K lights.

From Wikipedia: "The color temperature of a light source is the temperature of an ideal black-body radiator that radiates light of comparable hue to that of the light source"

Lucas · #36 02-20-2015, 12:44 PM

Yes, color temp has nothing to do with the concept of temp we all know.

It is a measure of the balance of amount of red or blue light. Hotter is blue. It's a stranger concept to wrap your head around. But if you look at those fluorescent bulbs, they often say "warm or cool".

Well you answered the question. The bulbs heat the oil to 100 degrees. So that's how hot the bulb is.

I'm still in with cycling it. It will never get that hot and it gives time for osmosis. Wait is heat transfer osmosis? Not really. But you get what I mean.

Someone do this test. See how long it takes.

funola · #37 02-20-2015, 12:51 PM

OK this these are the charts I was looking for. Tungsten filament temperature is 3000 C, 3300 K, 5000 F

Temperature of an Incandescent Light Bulb

https://www.google.com/search?q=temperature+of+glow+chart&rlz=1CATAAB_enUS627US627&espv=2&biw=1097&bih=554&tbm=isch&imgil=fyv_FH6ALf7SQM%253A%253BZDsb6bE-teF6DM%253Bhttp%25253A%25252F%25252Fwww.hearth.com%25252Ftalk%25252Fwiki%25252Fknow-temperature-when-metal-glows-red%25252F&source=iu&pf=m&fir=fyv_FH6ALf7SQM%253A%252CZDsb6bE-teF6DM%252C_&usg=__998m0U_oSDH7_t0NwG6ykYeO3co%3D&dpr=1.75&ved=0CCsQyjc&ei=sGTnVMmOKPK0sASls4KgCg#imgdii=_&imgrc=fyv_FH6ALf7SQM%253A%3BZDsb6bE-teF6DM%3Bhttp%253A%252F%252Fwww.hearth.com%252Ftalk%252Fattachments%252Fmetal-color-temp-chart-png.100306%252F%3Bhttp%253A%252F%252Fwww.hearth.com%252Ftalk%252Fwiki%252Fknow-temperature-when-metal-glows-red%252F%3B744%3B613

moon161 · #38 02-20-2015, 02:01 PM

Quote:

Originally Posted by Lucas

Yes, color temp has nothing to do with the concept of temp we all know.

It is a measure of the balance of amount of red or blue light. Hotter is blue. It's a stranger concept to wrap your head around. But if you look at those fluorescent bulbs, they often say "warm or cool".

Well you answered the question. The bulbs heat the oil to 100 degrees. So that's how hot the bulb is.

I'm still in with cycling it. It will never get that hot and it gives time for osmosis. Wait is heat transfer osmosis? Not really. But you get what I mean.

Someone do this test. See how long it takes.

An ideal 'black body' emits light per the frequency distribution defined by Planck's Law

Planck's law - Wikipedia, the free encyclopedia

The filiment of a light bulb is close, but the fluorescent powder on the inside of a fluorescent light is a horse of a different color, but composed to simulate the black body radiation spectrum.

Light bulbs don't burn your fingers off because the vacuum in the bulb permits a large temperature difference between the glass wall and the glowing filament.

Lucas · #39 02-20-2015, 02:16 PM

Just kelvin.

It's a concept for photographers mainly. You remember when you got film developed back in the day and everyone looked orange or pail? That developer didn't know color temp.

When I shoot with my digital I take a pic of a white piece of paper. I can tell the camera that it is true white, or shoot in raw format which is basically like film. Develop on the computer and use that original white paper to and set the color temp so the paper is true white.

So color temp is a measurement the of the light spectrum. Completely different.

I'm looking foreword to your test though.

vstech · #40 02-20-2015, 03:00 PM

The fingers are not burned off because they don't stay on the surface of the bulb long enough. .. it's very rare to find an evacuated light bulb... Light Bulb Structure - HowStuffWorks
Nearly all are filled with a non reactive gas argon most commonly. .. the oil in funola's drum only gets to 100F because of the wattage of the filiment and the volume of oil surrounding the bulb... put the same bulb in a saucepan of oil and it would eventually burst into flames...

Tungsten melts at 9000F
Take it out of the bulb and the element achieves oxidation point and burns up. Color temp is irrelevant to bulb temp... but the brightness of the filiment does show the temp of the wire itself is above 2500F

Quote:

Originally Posted by moon161

An ideal 'black body' emits light per the frequency distribution defined by Planck's Law

Planck's law - Wikipedia, the free encyclopedia

The filiment of a light bulb is close, but the fluorescent powder on the inside of a fluorescent light is a horse of a different color, but composed to simulate the black body radiation spectrum.

Light bulbs don't burn your fingers off because the vacuum in the bulb permits a large temperature difference between the glass wall and the glowing filament.

strelnik · #41 02-20-2015, 03:23 PM

Quote:

Originally Posted by vstech

The fingers are not burned off because they don't stay on the surface of the bulb long enough. .. it's very rare to find an evacuated light bulb... Light Bulb Structure - HowStuffWorks
Nearly all are filled with a non reactive gas argon most commonly. .. the oil in funola's drum only gets to 100F because of the wattage of the filiment and the volume of oil surrounding the bulb... put the same bulb in a saucepan of oil and it would eventually burst into flames...

Tungsten melts at 9000F
Take it out of the bulb and the element achieves oxidation point and burns up. Color temp is irrelevant to bulb temp... but the brightness of the filiment does show the temp of the wire itself is above 2500F

I would like to congratulate the mnany fine technicians who have added to this thread.

When I do my experiment, I will post temp data using the dipstick warmer I have.

I also have in mind a second experiment to determine the actual temp of the dipstick heating surface. If it is above 350, then it's going to be doing some damage to the oil

moon161 · #42 02-20-2015, 03:57 PM

Quote:

Originally Posted by vstech

The fingers are not burned off because they don't stay on the surface of the bulb long enough. .. it's very rare to find an evacuated light bulb... Light Bulb Structure - HowStuffWorks
Nearly all are filled with a non reactive gas argon most commonly. .. the oil in funola's drum only gets to 100F because of the wattage of the filiment and the volume of oil surrounding the bulb... put the same bulb in a saucepan of oil and it would eventually burst into flames...

Tungsten melts at 9000F
Take it out of the bulb and the element achieves oxidation point and burns up. Color temp is irrelevant to bulb temp... but the brightness of the filiment does show the temp of the wire itself is above 2500F

tyl604 · #43 02-20-2015, 04:11 PM

Well, I just use a drop cord and 100W lightbulb under the pan. In Atlanta's weather that seems to work fine if you use say 5W oil. 1981 300SD.

OM617YOTA · #44 02-20-2015, 04:50 PM

I'm interested in the results of this test. Love data, and would love another option for heating my engine. I can't get the block heater cord to work reliably so I've been starting cold no matter what the temp, and would love another option.

funola · #45 02-20-2015, 05:03 PM

Quote:

Originally Posted by tyl604

Well, I just use a drop cord and 100W lightbulb under the pan. In Atlanta's weather that seems to work fine if you use say 5W oil. 1981 300SD.

What, no welding? That's too simple and cheap to make! If you build a small plywood box for the light bulb that fits around the oil pan tightly, it would make it more efficient. Add more light bulbs as needed to increase wattage.