MembersPage/JanSaenen/Vapourised (2006-02-22 17:14:18)

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Input variables where Inj_out is dependant of with vapourised injection

Bosch 0 281 002 576

Free ADC inputs mcp3208:

injection pulsewidth calculation

  • I guess the fuel pulsewidth needs a *1/sqrt(fuel_pressure) multiplier (we'll likely use a table for sqrt() for speed.
  • I have no idea how the fuel temperature will be used. Most likely another table_lookup for viscosity ? ( --- I don't think viscosity of a gas varies much with temperature. Density does , by universal gas laws ; multiply calculated fuel amount by T/Tref - both in degrees K - to correct for that.)

When the plan is ready, we'll add to the firmware and make it possible to enable it in config.


software:

NTC resistance look-up table: \ MembersPage/NTC

Fuel pressure analog signal from sensor is calculated with:

Vout=(c1*Pabs+C0)*Us

Look-up table for multiplier: \ MembersPage/Fuel_Pressure

Nice data sheets for gasses:

http://www.airliquide.com/en/business/products/gases/gasdata/index.asp?GasID=53

With this graph of pressure and temperature of Propane:

Propane_Vapor_Pressure.GIF

Same graph for butane-n:

Butane_Vapor_Pressure.GIF