Results 1 to 2 of 2

Thread: Bar pressure at Combustion

  1. #1
    Join Date
    Oct 2014
    Lilyfield, NSW

    Bar pressure at Combustion

    G'day All,
    In my younger days I was an extreme off-roader and an old petrol head, recently I started working with Diesels & love them.
    If I had Diesels I probably would not have stalled in deep water so many times.

    However, can anyone here give me information on
    what the Bar pressure is inside the combustion chamber just prior to ignition, and a tad after ignition?

    Also does anyone know of a very small capacity (50cc) 4 stroke Diesel engine that has
    separate removable Cylinders ?
    In other words, cylinders Not cast into the block or have a easy removable Wet sleeve.

    I am going to build a small X4 cylinder Diesel engine with a max. 3'300RPM.
    Am also researching a 6 stroke design using Fuel & Steam!

  2. #2
    Join Date
    Sep 2005

    Re: Bar pressure at Combustion

    The pressure in the combustion chamber is the air pressure in the inlet manifold times the compression ratio (CR). Using 1 Bar as atmospheric pressure, this gives a pressure of 21 Bar for a CR of 21. (~300psi)
    If you then boost the inlet pressure the boost must be added to 1 Bar for the calculation. eg, a 0.5 Bar boost gives an air pressure of 1.5 Bar or 30.5 Bar.

    I do not know of any 50cc diesel engines, let alone any with removable sleeves.

    Life is a journey, with problems to solve, lessons to learn, but most of all, experiences to enjoy.

    Current Vehicles in stable:
    2000 Ford Courier Crew Cab 2.5L Turbodiesel on Blended veggie oil.
    '2014 Toyota Prius (on ULP)

    Previous Vehicles:
    '90 Mazda Capella. (2000 - 2003) My first Fatmobile. Converted to fun on veggie oil with a 2 tank setup. Died when supercharger stuck at max boost for weeks. Stretched head bolts.
    '80 Mercedes 300D. 2 tank conversion [Sold]
    '84 Mercedes 300D. 1 tank, no conversion. Replaced engine with rebuilt OM617A turbodiesel engine. Finally had good power. Donor for current Fatmobile coupe. (body parted out and carcass sold for scrap.)
    '99 Mercedes W202 C250 Turbodiesel (my darling Wife's car)[sold]
    '98 Mercedes W202 C250 Turbodiesel (my car)[sold]
    Parts Car C220 1993 SOLD.
    '85 Mercedes Benz W123 300CD Turbodiesel single tank using 95% used cooking oil and 5% to 10% misfuel (where someone had filled diesel vehicle with petrol).
    '06 Musso Sports Crew Cab. Running on used cooking oil with 5% to 10% misfuel. [Head gasket blew!]

    Searching the Biofuels Forum using Google
    Adding images and/or documents to your posts


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts