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Re: Purdue Versus Popular Mechanics which one gets money from the not so big three?

Fox Valley Technical College Dynamometer Test Analysis

          On July 8, 2008 a Model 40SS hydrogen generator was temporarily installed onto the Caterpillar C15 turbo-diesel engine attached to a Taylor engine dynamometer in the diesel lab.  A fresh baseline test was performed, followed by turning on the hydrogen generator and doing the same test procedure again with hydrogen gas production at 40-50 amps supplied by the alternator of the dynamometer engine.

At each of the following load % and RPM settings, data were recorded.  25%, 50%, 75%, and 100% load, 1200, 1400, 1600, and 1800 RPM.  Data recorded included horsepower, torque, hydrogen gas production rate, and the weight of the fuel tank at the beginning and end of each 5 and/or 10 minute test period beginning after the dynamometer was set for load % and RPM.  For the 25% load tests a 10 minute period was used for better accuracy, given the low fuel consumption.  During the test with Hydrogen Boost the 10 minute period was also used for the first few settings at 50% load, because the results were slightly better than expected and confirmation was desire by extending the test to 10 minutes to get double data.  The data was indeed confirmed with the extended period so after the first few extensions the 5 minute test period was resumed for the remainder of the tests. 

          The charts below represent the data and calculations after anomalies and miscalculations were corrected, including work achieved per unit of fuel consumed (HP hr/lb) and % improvements caused by the Hydrogen Boost.

PLEASE GO TO THE SITE FOR THE CHARTS!

Notice on this second chart an extra column is added to show the increase in HP hr/lb (horsepower hour per pound of fuel) expressed as a percent increase compared to the baseline figure for each data point.

These results were quite consistent with tests that were done over a year ago by Purdue University students and reported on in the May 2007 and September 2007 newsletter pages at www.hydrogen-boost.com Internet web site.  Noticed on both sets of results are areas in the operating envelope that showed major improvements and similar areas on both tests that showed only minor improvements.  Most notable was the mid RPM range of the 75% load data that had similar minor improvements.  This point may be when the unequipped diesel engine performs under optimum conditions and hence may confirm the theory that Hydrogen Boost gives the greatest benefit under “stressed combustion” as defined at http://www.hydrogen-boost.com/August%202007.html .

          Overall the Hydrogen Boost showed an average improvement in work done per unit of fuel burned of 16.4% over the operating range tested, but that should not be used to develop an expectation of 16% increase in mileage for a tractor trailer equipped with this common engine, especially if the majority of driving happens to be done at the lowest improvement data point (75% engine load and 1400 RPM) where only a 8.2% improvement was noticed.  However it should be noticed that a conservative adjustment in driving speed that brings the engine load closer to the 50% range and slightly lower RPM, would achieve the benefits of the Hydrogen Boost shown in that section of the chart above (50% engine load and 1300-1400 RPM), an improvement of 20-26%.  This would increase mileage due to reduced speed and wind resistance, but it would also take the best benefit of the Hydrogen Boost in relieving any stressed combustion caused by operating outside the sweet spot of the engine’s operation envelope.       

          It should also be noted that the benefits of the hydrogen injection are not usually evident in fuel mileage increase alone.  When a typical driver finds greater torque available it will be used in getting up the hills faster and therefore shorter trip times.  The ECM report analyses done on numerous fleet vehicles have shown notable increases in fuel mileage but also notable increases in average speed, top gear distance, top gear time, and idle time per gallon of fuel. 

          Notice the results reported below that were achieved with our hydrogen boost system installed on a tractor trailer owned by Titletown.

Parameter             Baseline    with Hydrogen 2^nd trip         3^rd trip         difference

Drive fuel economy 5.59 mpg     5.92 mpg      5.83 mpg      5.957mpg   up 6.56%

Average speed       54.4 mph      54.67 mph    54.4 mph      56.62mph   up 4.1%

Idle time per gallon 1.411 hr/gal 1.585 hr/gal  1.596 hr/gal  1.646hr/gal up 16.7 %

Top gear distance  71.5 %          78.4 %          78.1%           75.15%       up 5.1%

Top gear time        58 %             65.3 %          59.83%          64.16%       up10.6%

Mpg x mph             304.09          323.65          317.15          337.29       up 10.9%

This last parameter is a good overall calculation introduced by Hydrogen Boost in our August 2001 newsletter.  It takes into account both fuel mileage and average speed.