Yo Doc I haven’t found the white paper yet, but the below addresses painting components not quite as scientifically but I can find more.
Note the discussion was comparing hose Vs tubing.
“ Tube is Cool
Hydraulic tubing has some compelling advantages of its own. One of these is its superior heat transfer, especially if it’s painted.
One aspect of heat transfer is thermal radiation. The total radiation from an object is the sum of its reflection, emissivity and transmission of heat through the object.
When hydraulic tubing is painted, it reduces its reflectance and increases its emissivity, enabling better heat rejection, as this case study published in Hydraulics and Pneumatics magazine1 illustrates:
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An industrial hydraulic installation was originally designed to operate at 1,200 psi and at a maximum operating temperature of 120 degrees Fahrenheit (49 degrees Celsius). Zinc dichromate-coated steel tube distributes fluid from the 600-liter reservoir to the various stations around the plant. Over the years, the system had been added to (without any increase in installed cooling capacity)—to the point where it was now overheating in the summer months.
Because the system operated satisfactorily for 10 months out of the year, management did not want to spend the money necessary to upgrade the cooling system. So, one of the maintenance guys on staff who was familiar with the thermal radiation theory described earlier suggested painting the hydraulic system’s tubing.
Before proceeding, the maintenance team did a test. Team members applied electrical tape to two of the hydraulic tubes, and using an infrared camera, they measured the difference in temperature between the taped and untaped areas. They found the taped areas on the tubes were 7 degrees F (4 degrees C) cooler than the untaped areas.
This gave the maintenance team the confidence to proceed with the idea. Because the rest of the hydraulic system was painted flat white, the tubing was painted the same color.
And, the result? A week and 12 cans of spray paint later, the system was running 10 degrees F (5.5 degrees C) cooler. This might not sound like much, but the end result meant that the hydraulic system could now operate through the two hottest months of the year without overheating. It also meant that the need to increase installed cooling capacity was at least deferred, if not eliminated.”
There are many things in life we believe that are untrue! Maybe at your advanced age and rate ov dEcAY, learnin aiNt n0 longer possible?
Some of my initial description of why, may be incorrect!
TY
Red
