Question

An engine cylinder has a stroke of 320mm and bore 280MM. Calculate the mass of air contained in the cylinder if it is filled with air at 101.3 KPa at 13C at BDC.

Answer 1

Answer:

The mass of the air is 0.0243 kg.

Explanation:

Step1

Given:

Stroke of the cylinder is 320 mm.

Bore of the cylinder is 280 mm.

Pressure of the air is 101.3 kpa.

Temperature of the air is 13°C.

Step2

Calculation:

Stroke volume of the cylinder is calculated as follows:

$V=\frac{\pi }{4}d^{2}L$

$V=\frac{\pi}{4}\times(\frac{280}{1000})^{2}\times(\frac{320}{1000})$

V = 0.0197 m³.

Step3

Assume air an ideal gas with gas constant 287 j/kgK. Then apply ideal gas equation for mass of the air as follows:

PV=mRT

$m=\frac{PV}{RT}$

$m=\frac{101.3\times 1000\times 0.0197}{287\times (13+273)}$

m= 0.0243 kg.

Thus, the mass of the air is 0.0243 kg.