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Unexpected unit of input error (Heat transfer in solids)

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Hi,
I'm modeling skin and hair heating by laser beam distributed as Gaussian, very similar to the tutorial of: laser_heat_transient_pulsed.mph, only my model is 2D axisymmetric
I set the parameters: Ac (absorption coefficient) [1/m], Rc (refractive index) [unitless], Q0 (max laser power) [W], r_spot (laser radius) [m].
the variable I try to set is:
Q0*(1-Rc)*Ac*(1/(pi*(r_spot^2)))*an1(r)*exp(-Ac*abs(z))*an2(t)
where an1(r) is the Gaussian beam distribution: exp(-((r^2)/(2*(r_spot)^2)))
and an2(t) is a rectangle 3 pulses of laser.
I have an error of "Unexpected unit of input" on the Q0*(1-Rc)*Ac*(1/(pi*(r_spot^2)))*an1(r)*exp(-Ac*abs(z))*an2(t) expression, also if i remove the pulsed part of an2(t).

Can you please advise what is wrong with the expression?
Thanks a lot!
Anna


0 Replies Last Post 2 sept. 2017, 05:49 UTC−4
COMSOL Moderator

Hello Anna Spector

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