Question

calculate the efficiency of a gas engine working in otto cycle if the diameter of the cylinder is 16cm and the length of stroke is 25cm. the ratio of the heat capacities of the gas y= 1.4 and the dead volume (v1) is 1200cc​

Answer 1

Answer:

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Answer 2

Given:-

Diameter of cylinder, d=16cm

Length of stroke, l=25cm

Specific heat ratio, $\gamma=1.4$

Dead Volume, $\tex{V_{c}}=1200\tex{cm^{3}}$

To Find:-

Efficiency of otto cycle

Explanation:-

$\tex{Stroke Volume, V_{s}}=\frac{\pi}{4}\times d^{2}\times l\\\\\tex{V_{s}}=\frac{\pi}{4}\times16^{2}\times25\Rightarrow\tex{V_{s}}=5026.548\tex{cm^{3}}$

$\tex{Clearance Volume, V_{c}}=1200\tex{cm^{3}}$

$\text{Now,}\\\\\text{Compression ratio,r}=\frac{\text{Total Volume}}{\text{Clearance volume}}=\frac{V_{t}}{V_{c}}\\\\\text{r}=\frac{V_{c}+V_{s}}{V_{c}}=\frac{5026.548+1200}{1200}=5.1888$

$\text{Formula to calculate otto cycle efficiency is given by:-}\\\\\eta_{o}=1-\frac{1}{r^{\gamma-1}}\\\\\eta_{o}=1-\frac{1}{5.1888^{1.4-1}}}=0.4824$