Hi folks,
First my apologies. I should have had this data in a format ready to go when I started this post.
I have no excuses even though the volume of data I have is immense.
When you run three tests, (Idle, Stop and Go and Highway), four time each for before the louvers and after the louvers, using 48 temperatures sensors each taking and recording a reading every 3 seconds you end up with more then a quarter of a million data elements.
Needless to say these data elements are organized, yet it has been a challenge to get this data in a format that I can easily explain.
Here is my attempt.
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Temperature Performance Reporting
As I mentioned, I ran each of the three tests (Idle, Stop and Go, Highway), with and without louvers, four times, with and without the louvers installed.
Rather then report an average of how each setup did for all four testing cycles I have elected to report this data in the following way.
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I have chosen to use the test data from the ?Pre-Louver Testing? that reflexes the absolute Best Performance (lowest air temp readings) of the four test cycles.
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In other words,
the data I am showing in the chart below reflects the LOWEST Temperature Recording for one of the four tests cycles I performed, Without the Louvers.
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2. Likewise, I have chosen the absolute Worst Performance (highest temp readings), of the four test cycles With the Louvers Installed.
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the Louver Temperature numbers are the HIGHEST temperatures recorded from one of the four test cycles, With the Louvers Installed.
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I feel that comparing the Best Performance Without the Louvers to the Worst Performance With the louvers will present a pretty good picture of what you can expect if you where to do the same implementation on your TJ.
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Temperature Performance Results
This chart illustrates two major points of each of the three tests, comparing the air temperature performance before and after the louvers were installed.
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High Temperature
The HIGH temperature indicates the absolute highest temperature recorded on ANY of the 48 sensors at ANY time during the test. Please understand this is one temperature at one moment in time, the single highest under hood air temp recorded during the test.
For example;
During the Idle Test, before the louvers where installed, the highest under hood air temperature recorded on any of the 48 sensors was 267 degrees F.
The Highest temperature recorded on any of the 48 sensors during the Stop and Go test after the louvers were installed was 227 degrees F.
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Average Temperatures
The Average Temperature is the average of ALL temperatures recorded by ALL 48 Sensors (ever 3 seconds) during the full duration of the test. The Average Temperature is illustrated with a red line on each vertical bar.
For example;
The Idle Test was conducted over a 15 minute period of time, using 48 sensors, each recording a temperature every 3 seconds. This creates 14,400-temperature reading which are used to generate this average.
The intent is to give a fairly good picture of the general under hood air temperatures relative to having louvers or no louvers installed.
The YELLOW bars represent the test data captured BEFORE the louvers where installed.
Likewise, the BLUE bars reflect the test data captured AFTER the louver where installed.
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Analysis
As you would expect, across the board, the under hood air temperatures are consistently lower with the louvers installed.
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High Temperatures
High Temperatures came in as follows.
Idle Air Temps were - 23 degrees cooler
Stop and Go Air Temp were - 35 degrees cooler
Highway Air Temps were ?27 degrees cooler
When the Louvers are installed.
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Average Temperatures
Idle was - 11 degrees cooler
Stop and Go ?16 degrees cooler
Highway was ?27 degrees cooler
When the Louvers are installed.
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Under Hood Temperature Patterns
I did not want to just post the above number and present that as a complete picture or understanding as to what is going on, air temperature wise under the hood with and without the louvers.
I wanted to present another view of the data I have.
If you remember, there are 48 sensors, each taking a reading every three seconds during the life cycle of each test.
In the chart below I am illustrating
How Many of the 48 sensors Recorded a Temperature ABOVE 200 degrees F more then 50% of the time.
In other words, each of the 48 sensors during the Idle Test recorded 300 readings. If 151 or more of the 300 readings were Above 200 F then that sensor is shown Above the Bar in the Chart.
If 150 or more of the 300 readings were Under 200 F then that sensor is shown Below the Bar in the Chart.
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Not only are the under hood air temperatures lower with the louvers then without them, but I believe the heat distribution under the hood is far better with the Louvers; Less hot spots!
I do plan to do another chart like which will reflect a higher percentage. In other words, how many sensors recorded temperatures above 200 degrees F more then 75% of the time.
This effort will have to wait till later.
Other Thoughts
Across the board, the under hood air temperatures on my TJ have been reduced. The greatest benefit appears to come at highway speeds. This is probably happening as a result of an increased volume of air coming through the radiator and an increased vacuum on top of the hood louvers cause by the higher speed.
I do not know this as fact, but logic and physics leads me to believe this.
My friend William has given me an idea that I wish to pass along.
I would imagine the under hood air temperatures could be reduced farther, especially during idle and stop and go travel simply by mounting two pancake fans on the underside of the louvers or drip pans.
Given the drip pan are so inexpensive I may pick up an extra set and try this to measure the results.
I already have a plan for these louvers and drip pans.
Blaine and I have been doing a fair amount of research and experimenting with Evaporative Cooling. I intend to build an emergency cooler for both my power steering and engine oil when we get the bugs worked out. . These cooler will be mounted under the vents and will have both fans and an evaporative cooling element in the design.
You?d be amazed how much cooling can happen with a small mist of water, but that?s for another Auxiliary Cooling Topic.
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I hope I was able to explain accurately and in a way that is understandable and valuable what I am reporting here.
If not please let me know and I will take another shot at it.
Have a great day folks.
Frank