mm. The mechanical efficiency of the engine is 80%. Calculate the IMEP and the BMEP

  • 1
  • 135 Views
  • All levels

A compression ignition engine when tested gave an indicator card having area 3250mm^2 and length 73mm. The calibration factor was 0.2 bar/mm. The mechanical efficiency of the engine is 80%. Calculate the IMEP and the BMEP

Leave an answer

Our People Answers

0

(Based on todays review)

  • DeniceSandidge


    Answer:

    BMEP = 8.904 bar

    IMEP =  11.13 bar

    Explanation:

    given data

    area A = 3250 mm²

    length L = 73 mm

    calibration factor = 0.2 bar/mm

    mechanical efficiency = 80 %

    to find out

    IMEP and the BMEP

    solution

    first we calculate the BMEP break mean efficiency pressure tat is express as

    BMEP = \frac{A}{L}

    here A is area and L is length

    so BMEP is

    BMEP = \frac{3250}{73} = 44.52 mm

    BMEP = 44.52 × 0.2 bar = 8.904 bar

    and

    we know mechanical efficiency is

    mechanical efficiency = \frac{BMEP}{IMEP}

    so put here value we get IMEP

    IMEP = \frac{8.904}{0.80}

    IMEP =  11.13 bar