BMEP Calculator

Calculate Brake Mean Effective Pressure for engine performance comparison

Calculate Brake Mean Effective Pressure

Number of revolutions per power stroke: 2

Brake torque output of the engine

Total swept volume of all cylinders

BMEP Results

0.0
kPa
0.000
bar
0.0
psi
0.000
atm

Formula: BMEP = (2π × n × T) / D

Where: n = 2, T = 0.00 N⋅m, D = 0.000e+0

Engine type: four-stroke

Engine Performance Analysis

Example Calculation

Four-Stroke Engine Example

Engine Type: Four-stroke (n = 2)

Torque: 160 N⋅m

Displacement: 2000 cc = 0.002 m³

Calculation Steps

BMEP = (2π × n × T) / D

BMEP = (2π × 2 × 160) / 0.002

BMEP = (2010.6) / 0.002

BMEP = 1,005,300 Pa = 1,005.3 kPa

Engine Types

2T

Two-Stroke

n = 1 revolution/stroke

Higher power density

4T

Four-Stroke

n = 2 revolutions/stroke

More efficient, cleaner

C

Custom

Variable n value

Experimental engines

Improve BMEP

Increase compression ratio

Supercharging or turbocharging

Optimize air-fuel mixture

Reduce stroke length

Improve combustion efficiency

Understanding Brake Mean Effective Pressure (BMEP)

What is BMEP?

Brake Mean Effective Pressure (BMEP) is a measure of the average pressure across the pistons that produces torque at the crankshaft. It's a crucial performance metric used to compare engines of different sizes and types.

Why is BMEP Important?

  • Enables fair comparison between different engines
  • Indicates engine efficiency and performance
  • Helps optimize engine design and tuning
  • Relates directly to torque output

BMEP Formula

BMEP = (2π × n × T) / D

  • BMEP: Brake Mean Effective Pressure (Pa)
  • n: Number of revolutions per power stroke
  • T: Brake torque (N⋅m)
  • D: Engine displacement (m³)
  • 2π: Constant for rotational motion

Note: Higher BMEP values indicate more efficient engines with better power-to-displacement ratios.

Typical BMEP Values

Naturally Aspirated Gasoline

800-1200 kPa

Turbocharged Gasoline

1200-2000 kPa

Diesel Engines

1000-2200 kPa