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Spent lunch going over the Madyira and Harding paper and would like some insight into my comments below.
It states "The air-fuel ratio of the engine was calibrated at 30% load to a value of 14.7"
at what RPM? what was the AFR at other loads / RPMs? This is critical to assess the effect of the HHO with regard to stoichiometric combustion. Also, what is the %load referenced to?
Fig 4a shows significant issues in the graph of power vs RPM - power produced at 2500 RPM is nearly the same as 2000 - is this a problem with carburetion? Similarly, torque vs load (4b) does not look right. 4c & 4D seem to indicate an anomaly at 2000 RPM (is this a lean spot?) Figure 5b seems to confirm this view that there are issues with mixture transition between idle and 2000 RPM at low loads.
"Figure 6(a) indicates that an increase in power can be achieved with the introduction of the hydrogen gas. There is more than 4% increase observed for a dynamometer load of 10% at an HHO inclusion of 0.125%. However, the gain is quickly lost as HHO percentage increases. This reinforces the hypothesis that only a small percentage of hydrogen is required to improve combustion properties." How is this contention supported? The gains at 10-20% load can possibly be explained by the previously mentioned lean transition area.
"It can be seen that the SFC is more than 20% lower under 0% load conditions at 0.2% HHO inclusion." I am at a loss as to how you can calculate SFC for a 0 load condition. I feel it is more likely is that the HHO provided the additional chemical energy to reduce fuel consumption at idle.
I am not trying to be argumentative, just seeking to understand how the conclusions were arrived at and to fathom out whether there is really a gain to be had.
Simon
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