Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Precombustion chamber and compression chamber

  1. Jun 23, 2009 #1
    i 'd like to ask abt the difference between precombustion chamber and compression chamber which used in diesel engines (indirect injection)??
  2. jcsd
  3. Jun 23, 2009 #2


    User Avatar
    Science Advisor
    Gold Member

    What do you want to know? Indirect injection has traditionally been used for small, high-speed engines where the rapid fuel-air mixing required is achieved by air being forced into an auxiliary combustion chamber toward the end of the compression stroke. This chamber promotes highly turbulent flow, and when the fuel is injected, high mixing rates can be achieved. The resulting pressure rise causes the combustion gases to expand into the main chamber, where combustion continues, and the resulting turbulence aids complete combustion. A direct injection design (as seen on traditional large diesel engines, and in modern small engines) puts the combustion chamber into the piston bowl, and relies on inlet port and piston design to create the necessary turbulence for combustion.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook