Respuesta :
Answer:
a). 5 cylinders
b). 3 cylinders
Explanation:
To develop a gasoline engine that produces
Power, P = 300 hp
= 300 x 746 = 223710 watt
at speed, N = 600 rpm = 100 rps
and stroke volume [tex]$V_s=0.5$[/tex] L
= [tex]$0.5 \times 10^{-3}\ m^3$[/tex]
a). A naturally aspirated engine
BMEP at peak power = 10 bar
= [tex]$10 \times 10^5\ N/m^2$[/tex]
Suction volume, V = [tex]$V_s \times N$[/tex]
= [tex]$0.5 \times 10^{-3} \times 100 = 0.05\ m^3/s$[/tex]
Power produced in one engine cylinder , p = BMEP x V
= [tex]$10 \times 10^5 \times 0.05$[/tex]
= 50000 watts
No. of cylinders required, n = [tex]$\frac{P}{p}$[/tex]
= [tex]$\frac{223710}{50000}$[/tex]
= 4.47
So number of cylinders ≈ 5 nos.
b). A turbo charged engine
BMEP = 20 bar = [tex]$20 \times 10^5\ N/m^2$[/tex]
and Volume V = [tex]$0.05\ m^3 /s$[/tex]
Power produced in one engine cylinder, p = BMEP x V
= [tex]$20\times 10^5 \times 0.05$[/tex]
= 100000 watts
Therefore, number of cylinders, n = [tex]$\frac{P}{p}$[/tex]
= [tex]$\frac{223710}{100000}$[/tex]
= 2.23
So number of cylinders ≈ 3 nos.
