Oil Canister Heat Sink Supporting Data & Test Results
The Data Behind Heat Sinks
A heat sink works to dissipate heat because a metal is used that is a high conductor of heat, measured by what is called its thermal conductivity. You’ve commonly seen them on the back of computer chips (and LED headlights!). Aluminum is highly conductive compared to steel which is why it’s often used. Pure aluminum is the best with a thermal conductivity of 247 watts/m·K but it’s expensive and not as easy to work with as an alloy. These heat sinks are made with 6061, a high quality magnesium and silicon alloy with a high thermal conductivity of 151–202 watts/m·K. For comparison, carbon steel is around 50 watts/m·K.
Tests Conducted by a former Manufacturer
Castrol GTX 10W30 motor oil was heated to a temperature of 220 degrees F. and pumped simultaneously through two identical oil filters. One oil filter had a heat sink attached, the other did not. A fan was used to direct seventy degree F. ambient air over both oil filters at a velocity of fifty miles per hour. The oil exiting the filter having the heat sink installed indicated a heat removal approximately equal to two degrees per minute. Whereas the oil temperature exiting the filter without the heat sink showed no change. (Typically an automotive engine passes all the oil through the filter more than once per minute)
With a constant heat source applied to the oil, the temperature dropped to 202 degrees F (from 220 degrees F.) with five minutes. This translates to a 12% temperature decrease of the heat added to ambient temperature.
Air Cooled Engine (Road Test)
The test vehicle used was a 1978, 911SC Porsche, equipped with a Carrera style oil cooler. The car was driven 65 MPH on a 85 degree day for approximately 35 miles. The car was then stopped and a I.R. thermometer was used to check the temperatures at various points along the oil lines, tank and cooler. In addition, the reading on the dash temperature gauge was noted. An average temperature of 220 degrees was logged. Testing was then resumed, with the heat sink installed on the oil filter, over the same course and speed.
At the end of the 35 miles the temperatures were then checked again using the infra-red thermometer at the same points as before. The indicated temperature readings showed an average reading of 208 degrees, a reduction of 12 degrees.
Liquid Cooled Automotive Engine (Road Test)
This test was an actual highway test. The car used was a late model Corvette equipped with digital readout oil temperature and coolant temperature gauges. On a 72 degree F. day, at 65 miles per hour, the oil temperature read a constant 221 degrees F. The water temperature was 195 degrees. The Corvette was then pulled off the road and a heat sink was installed. Testing was then resumed. Within a distance of five miles the heat sink was responsible for lowering and maintaining the oil temperature at 203 degrees F.
Our tests again indicated a 12% approximate reduction above ambient temperature of oil heat. On similar testes, it was found that after installation of the heat sink the oil temperature will typically drop near to the level of the engine coolant temperature.