Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - View Single Post - The BSFC chart thread (post 'em if you got 'em)

bwilson4web · 04-07-2009, 09:16 AM

Hi,

I was surprised to find one of my charts in this thread so if there are any questions. As background, I have a Graham miniscanner that reports up to six data metrics in just over 1 second. There are nearly 100 metrics that can be chosen but only six recorded via the RS-232 line.

For these charts, I measured MG1 torque, which is 28% of the ICE torque. Combined with ICE rpm, I have the shaft power into the transaxle. For fuel flow, I can use either mass airflow or injector timing.

Initial Engine Efficiency Chart:

I prefer this chart because the small red bubbles do a better job of showing the peak efficiency region. It also includes the HP graph.

This is another look at similar data from a single fuel tank:

This is graph from one of the SAE papers on the Prius I was trying to replicate:

Data from another trip:

Now one of the Prius SAE papers on the Prius has this operational line:

So I made a variation of that chart:

This chart is a little easier to deal with because it uses engine RPM as the X-axis and the expected torque. Understand this is more of a model chart versus the earlier measured charts.

Bob Wilson

* - SAE 2004-01-0064 - "Development of New-Generation Hybrid
System THS II - Drastic Improvement of Power Performance and Fuel Economy", Koichiro Muta, Makoto Yamazaki and Junji Tokieda
Toyota Motor Corp. Reprinted From: Advanced Hybrid Vehicle Powertrains 2004 (SP-1833) 2004 SAE World Congress Detroit, Michigan March 8-11, 2004

04-07-2009, 09:16 AM	#134 (permalink)
bwilson4web Engineering first Join Date: Mar 2009 Location: Huntsville, AL Posts: 843 17 i3-REx - '14 BMW i3-REx Last 3: 45.67 mpg (US) Blue Bob's - '19 Tesla Std Rng Plus Thanks: 94 Thanked 248 Times in 157 Posts	Hi, I was surprised to find one of my charts in this thread so if there are any questions. As background, I have a Graham miniscanner that reports up to six data metrics in just over 1 second. There are nearly 100 metrics that can be chosen but only six recorded via the RS-232 line. For these charts, I measured MG1 torque, which is 28% of the ICE torque. Combined with ICE rpm, I have the shaft power into the transaxle. For fuel flow, I can use either mass airflow or injector timing. Initial Engine Efficiency Chart: I prefer this chart because the small red bubbles do a better job of showing the peak efficiency region. It also includes the HP graph. This is another look at similar data from a single fuel tank: This is graph from one of the SAE papers on the Prius I was trying to replicate: Data from another trip: Now one of the Prius SAE papers on the Prius has this operational line: So I made a variation of that chart: This chart is a little easier to deal with because it uses engine RPM as the X-axis and the expected torque. Understand this is more of a model chart versus the earlier measured charts. Bob Wilson * - SAE 2004-01-0064 - "Development of New-Generation Hybrid System THS II - Drastic Improvement of Power Performance and Fuel Economy", Koichiro Muta, Makoto Yamazaki and Junji Tokieda Toyota Motor Corp. Reprinted From: Advanced Hybrid Vehicle Powertrains 2004 (SP-1833) 2004 SAE World Congress Detroit, Michigan March 8-11, 2004 __________________ 2019 Tesla Model 3 Std. Range Plus - 215 mi EV 2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade Retired engineer, Huntsville, AL Last edited by bwilson4web; 04-07-2009 at 09:27 AM..