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Error: 7161 The mass matrix is zero - resolve

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Respected sir/ma'am,

I am trying to simulate a Nano ElectroMechanical Switch(NEMS) using the following modules:a)solid, stress-strain, b) Moving Mesh, and c)Electrostatics.
When i run the solver, it shows an error message:'Error: 7161 The mass matrix is zero' along with a warning: 'Not all domains are meshed'.
The sizes are in nano domain. Model is attached for your kind reference.
For meshing i used Mapped Meshing to reduce number of elements.
I am using Version 3.5a on Pentium processor with 32 bit and 2 GB RAM.

Thank You in advance


2 Replies Last Post 16 mar 2014, 08:46 GMT-4
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Hello Krishnachaitanya S

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Posted: 1 decade ago 14 apr 2013, 16:49 GMT-4
Hello Krishnachaitanya

Don't leave the value of the "Electric Conductivity" as zero. Go to material section and edit the value for each material you have. Give it some small value at least 1. I'm sure it'll resolve your problem.

Have fun.
Hello Krishnachaitanya Don't leave the value of the "Electric Conductivity" as zero. Go to material section and edit the value for each material you have. Give it some small value at least 1. I'm sure it'll resolve your problem. Have fun.

Mohanraj Ramachandran

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Posted: 1 decade ago 16 mar 2014, 08:46 GMT-4
Dear Sir,
Thank you in advance, Am simulating Thermoelectric generator using Seebeck effect by means of Weak contribution approach..

INPUT: temperature gradient between thermo couple (Temperature)
OUTPUT: voltage flow across thermo couple (Electric potential)

I rectified all my errors. I changed "materials density and poison ratio value.." also
but still it show "Error: the mass matrix is zero"

I have attached the error image here.. Please help me to overcome this error.

Dear Sir, Thank you in advance, Am simulating Thermoelectric generator using Seebeck effect by means of Weak contribution approach.. INPUT: temperature gradient between thermo couple (Temperature) OUTPUT: voltage flow across thermo couple (Electric potential) I rectified all my errors. I changed "materials density and poison ratio value.." also but still it show "Error: the mass matrix is zero" I have attached the error image here.. Please help me to overcome this error.

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