Calculating Young's Modulus for a Cylinder with Given Pressure and Bulk Modulus

AI Thread Summary
To calculate Young's modulus for a cylinder with a volume of 8000 m³, pressure of 80 MPa, and bulk modulus of 74 MPa, the user initially applies the formula for volumetric strain, yielding a value of 1.081. They then attempt to calculate Young's modulus using both stress and volumetric strain, resulting in two different values: 592.05 GPa and 88.8 MPa, both of which seem incorrect. The user considers revisiting the area of the cylinder to derive stress and strain but encounters low elastic modulus values. Clarification on the correct approach to calculating Young's modulus is sought, emphasizing the need for accurate formulas and values. The discussion highlights the complexities involved in material property calculations.
ErnieChicken
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Hey Guys, I am new to the forums but have seen you guys help a lot with pointing people in the right direction.

Here is my problem:
A Cylinder with a Volume of 8000m3 has a pressure of 80MPa, Bulk Modulus of 74 MPa. I need to calculate the Young s modulus and determine the material type.

So Far here is what i have:

Using Bulk Modulus, Volumetric Strain can be found:
Bulk Modulus K = Pressure / Volumetric Strain
Volumetric Strain = Pressure / Bulk Modulus K = 80 x 106 Pa / 74 x 106 Pa = 1.081
Volumetric Strain Can also be determined using this formula:
Volumetric Strain = Change in Volume / Volume
Then the Change in Volume can be found using the Volumetric Strain:
Change in Volume = Volumetric Strain x Volume = 1.081 x 8000m3 = 8648m3

My train of thought with calculating the youngs modulus is to use

E = Stress (Volume x Pressure) / Volumetric strain
So E = 592.05 GPa

Or by Using K
E = 3K(1-2v) --> 3x74MPa x (1-0.6) = 88.8MPa

But neither answer looks right. Have i overlooked something here?

Your input will be greatly appreciated.
 
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well. i think bulk modulus =direct stress/ vol strain .here pr stress
 
Thanks for the reply Praveen. I have looked at going back and getting the area of the cylinder and working through stress and strain but I am getting x10^6 numbers which is low for the elastic modulus.
 
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