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4 years ago

10

A compression ignition engine when tested gave an indicator card having area 3250mm^2 and length 73mm. The calibration factor wa

s 0.2 bar/mm. The mechanical efficiency of the engine is 80%. Calculate the IMEP and the BMEP

1 answer:

atroni [7]4 years ago

7 0

Answer:

BMEP = 8.904 bar

IMEP = 11.13 bar

Explanation:

given data

area A = 3250 mm²

length L = 73 mm

calibration factor = 0.2 bar/mm

mechanical efficiency = 80 %

to find out

IMEP and the BMEP

solution

first we calculate the BMEP break mean efficiency pressure tat is express as

BMEP = $\frac{A}{L}$

here A is area and L is length

so BMEP is

BMEP = $\frac{3250}{73}$ = 44.52 mm

BMEP = 44.52 × 0.2 bar = 8.904 bar

and

we know mechanical efficiency is

mechanical efficiency = $\frac{BMEP}{IMEP}$

so put here value we get IMEP

IMEP = $\frac{8.904}{0.80}$

IMEP = 11.13 bar

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4 years ago

Two concentric helical compression springs made of steel and having the same length when loaded and when unloaded are used to su

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Answer:

see explaination for all the answers and full working.

Explanation:

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4 years ago

Read 2 more answers

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3 years ago

A diesel engine with CR= 20 has inlet at 520R, a maximum pressure of 920 psia and maximum temperature of 3200 R. With cold air p

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Answer:

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So cut-off ratio $\dfrac{V_3}{V_2}=6.15$

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$\dfrac{T_3}{T_4}=(3.25)^{1.4 -1}$

$T_4=1997.5R$

So the exhaust temperature $T_4=1997.5R$

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4 years ago