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3 years ago

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A 4 stroke over-square single cylinder engine with an over square ratio of 1.1,the displacement volume of the engine is 245cc .T

he clearance volume is 27.2cc the bore of this engine is ?

1 answer:

julia-pushkina [17]3 years ago

6 0

Answer:

10.007

Explanation:

Assuming we have to find out the compression ratio of the engine

Given information

Cubic capacity of the engine, V = 245 cc

Clearance volume, V_c = 27.2 cc

over square-ratio = 1.1

thus,

D/L = 1.1

where,

D is the bore

L is the stroke

Now,

Volume of the engine V = $\frac{\pi}{4} D^2L$

plugging values we get

245 = $\frac{\pi}{4} D^3/1.1$

Solving we get D =7 cm

therefore, L= 7/1.1 =6.36 cm

Now,

the compression ratio is given as:

r =(V+V_c)/V_c

on substituting the values, we get

r = (245+27.2)/27.2 =10.007

Hence, Compression ratio = 10.007

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To find convection heat transfer coefficient at 1 m from leading edge,

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