The pressure generated in an object by thermoelastic expansion due to a very short laser pulse is described:
The energy deposition W = μaH [J/m3].
The temperature rise ΔT = (energy deposition)/(rho Cp) [degree C].
The strain ε = βΔT [dimensionless].
The stress or pressure = Mε [J/m3] = [kg/(m s2] = [Pa].
The Grueneisen coefficient Γ = Mβ/(ρ Cp) [dimensionless].
The units of pressure (P) are (force)/(area). The units of energy deposition (W) are (energy)/(volume) = (force x distance)/(area x distance) in which the distance term cancels to equal (force)/(area). Hence the units of pressure and energy deposition are identical. The conversion factor for pressure is 1 J/m3 = 1 Pa = 10-5 [bar].
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