AM AirFlow

AM AirFlow

Calculate the Air Flow in an engine

Multiple Choice

We are given the bore and the stroke. Which if these is the height of the cylinder?

• Bore

• Stroke

• Neither

Multiple Choice

The bore is what measurement for our calculations?

• The Height of the cylinder

• The radius of the cylinder

• The diameter of the cylinder

• None of the others

Kia Soul 2019 Base Model 4 cylinder

Bore of 77mm and a stroke of 85.44. Find the volume of the individual cylinder in cm^3, the volume of the whole engine in cm^3, and the volume of the engine in Liters.

So first convert to cm by dividing bore and stroke by 10. Then use the cylinder formula to calculate a single cylinder: pi(bore/2)^2*(stroke).

Round your answer to hundredths (two numbers after the decimal)

Calculate the whole enginge by multiplying by the number of cylinders.

Then convert the cm^3 to Liters by dividing by 1000. Round all answers to hundredths.

Fill in the Blank

The volume of a single cylinder in the Kia Soul with bore of 77 mm and stroke of 85.44 mm rounded to hundredths is _______________.

Fill in the Blank

The volume of the whole engine in hundredths is:

Fill in the Blank

The volume of the engine in Liters is hundredths is ___________________________.

Now we are working on air flow

• Air flow is measured in grams/second

• The Liters of the engine will tell us how much air will fill the engine every two revolutions of the engine

• We will need to multiply by the number of revolutions per minute

• Then we need to convert from Volume to Mass by using 1.29 grams = 1 Liter

• Then convert from minutes to seconds

• Multiply by the throttle % and Volumetric Efficiency% as decimals.

Finding the air flow with a 1.65 L vehicle, 1100 idle at 12% throttle and 84% Volumetric Efficiency

 $\frac{1.65L}{1\ fill}\cdot\frac{1.29g}{1L}\cdot\frac{1fill}{2rev}\cdot\frac{1100rev}{\min}\cdot\frac{1\min}{60\ Sec}\cdot\left(0.12\right)\cdot\left(0.84\right)=\frac{1.97grams}{\sec}$  

Fill in the Blank

Find the airflow of a 4.2 L engine at 7200 rpm at 95%throttle and 88% Volumetric efficiency rounded to hundredths.