Five9Dak
04-18-2008, 04:45 AM
Here is an experiment I did for extra credit for my fluid dynamics class using Dave Downing's motor while it was on the engine dynamometer. Thought you guys would find it interesting.
Link: http://www.youtube.com/watch?v=VfYMSrgCG1s
Summary:
This is a video of an experiment I conducted to test the effects of air filters on the performance of carbureted internal combustion engines. The test engine was mounted on a dynamometer to measure its horsepower and torque output. The only variable in the test was the air filter type; all other controllable variables were kept constant by the dynamometer software and the conditioned air in the test cell. The three different configurations tested were with no air filter, with a standard high performance air filter, and with a filter media top high performance filter. The filter media top is advertised to increase power production by reducing intake restriction through increased filtering surface area. The experiment sought to test this claim. The results were a bit surprising. The open carburetor made the most power, followed by the stand high performance filter and lastly the filter media topped air filter. It can be postulated that the filter media top added additional turbulence to the inlet of the carburetors venturies reducing flow and hindering fuel metering of the carburetor. An alternate hypothesis is that the filter top media was much closer to the venturies, shortening the effective entrance length from 4-5” (radius of the filter) to less than 1” (height of the filter) Explaining the observed phenomena is beyond the scope of this experiment and my knowledge, but it is evident that money is better spent elsewhere when modifying a carbureted engine for performance than on a filter media top for the air filter.
Relation to Fluids:
A running internal combustion engine is an extremely complex dynamic fluid system, but it can be reduced to an air pump for simple analysis. Maximizing performance of the engine is most generally achieved by increasing pumping efficiency. This experiment touched on a few of the concepts we learned in class. Pressure drop across the filter media, as well as perturbation of the flow is the primary reason for flow and therefore power loss through an air filter. Carburetors work off the venturi principle and they seem to function best with infinite entrance lengths, i.e. being open to atmosphere.
Why I chose this topic:
I chose to conduct this experiment because it plays close to my interests and what I want to do with my degree upon graduation. High performance automobiles have always been my passion and it was an easy decision to do something automotive related for this project. ME320 has my furthered knowledge of how engines operate and most importantly, how to make them more efficient.
Link: http://www.youtube.com/watch?v=VfYMSrgCG1s
Summary:
This is a video of an experiment I conducted to test the effects of air filters on the performance of carbureted internal combustion engines. The test engine was mounted on a dynamometer to measure its horsepower and torque output. The only variable in the test was the air filter type; all other controllable variables were kept constant by the dynamometer software and the conditioned air in the test cell. The three different configurations tested were with no air filter, with a standard high performance air filter, and with a filter media top high performance filter. The filter media top is advertised to increase power production by reducing intake restriction through increased filtering surface area. The experiment sought to test this claim. The results were a bit surprising. The open carburetor made the most power, followed by the stand high performance filter and lastly the filter media topped air filter. It can be postulated that the filter media top added additional turbulence to the inlet of the carburetors venturies reducing flow and hindering fuel metering of the carburetor. An alternate hypothesis is that the filter top media was much closer to the venturies, shortening the effective entrance length from 4-5” (radius of the filter) to less than 1” (height of the filter) Explaining the observed phenomena is beyond the scope of this experiment and my knowledge, but it is evident that money is better spent elsewhere when modifying a carbureted engine for performance than on a filter media top for the air filter.
Relation to Fluids:
A running internal combustion engine is an extremely complex dynamic fluid system, but it can be reduced to an air pump for simple analysis. Maximizing performance of the engine is most generally achieved by increasing pumping efficiency. This experiment touched on a few of the concepts we learned in class. Pressure drop across the filter media, as well as perturbation of the flow is the primary reason for flow and therefore power loss through an air filter. Carburetors work off the venturi principle and they seem to function best with infinite entrance lengths, i.e. being open to atmosphere.
Why I chose this topic:
I chose to conduct this experiment because it plays close to my interests and what I want to do with my degree upon graduation. High performance automobiles have always been my passion and it was an easy decision to do something automotive related for this project. ME320 has my furthered knowledge of how engines operate and most importantly, how to make them more efficient.