Of course. The issue is not whether a thermocouple can be placed under insulation on a pipe. It's a thermocouple being placed at a union with steam (theoretically) on one side and 38C water on the other. I address the insulation only as it spans both the hot and cold side, creating a common air pocket, where the thermocouple is sharing room with the potentially hot brass. Your test with two inputs on the same conductive material, if your using essentially the same equipment, could alleviate other concerns of electrical current between the thermocouple leads, but that's about it.
To: [email protected] Subject: Re: [Vo]:Will tests surface mounted thermocouples on pipe From: [email protected] Date: Wed, 7 Dec 2011 18:22:26 -0500 Jed, to be a good test you would need to have a hot pipe connected metallically a short distance from the cold pipe you were measuring. It would be ideal if you could obtain a heat exchanger and make a setup very much like Rossi's. I do not think anyone would doubt that the temperature of the pipe exterior would reflect that of the water within unless another source of heat is contributing. Dave -----Original Message----- From: Jed Rothwell <[email protected]> To: vortex-l <[email protected]> Sent: Wed, Dec 7, 2011 6:04 pm Subject: [Vo]:Will tests surface mounted thermocouples on pipe I wrote: Try placing at thermocouple on a hot pipe, in various spots, under various covers. You will find the differences are insignificant. I did this years ago, working at Hydrodynamics. I happen to have a nice dual input thermocouple, with a T1 - T2 mode, so I will try it again with a copper hot water pipe, with and without insulation and so on. I will do this under the kitchen sink. Varying water temperatures do not matter because I am looking for a difference between T1 and T1 (when they are mounted differently), and the response is quick. I have insulated all of the hot water pipes in my house foam pipe insulation. Look it up at Lowe's. It works remarkably well. Anyway, I'll try it with and without that, in air, under bubble wrap and a few other ways. I have different kinds of probes too. I use a shielded probe for cooking turkey. I'll just use the regular ones for this test. I can compare the actual fluid temp to the pipe temp if you like. I'll bet it is the same to within 0.3 deg C. You people should do stuff like this, instead of blabbing for weeks at a time about magic pots full of water that do not cool down. - Jed
