Re: NEC-LIST: Unusual modeling problem

EM values for some substances:

Ref. Perfect cond. ep-r=1, sigma=infinity (mho/m or Siemens/m)
Ref. Copper 1, 5.8x10E+7

Sea water 70, 5 (sigma ranges 0.7-7)
Fresh water 80, 0.03
Pure water 80, 0.0017
Distilled water 80, 0.0001

Rice paddy 34, 0.15
Marsh 30, 0.11

Wet ground 30, 0.01
Medium dry ground 15, 0.001
Rich moist farmland 23, 0.065
Pastoral hills 13, 0.011
Wet soil 5 to 25, 0.011 to 0.001
Dry soil 2 to 6, 0.004 to 0.0001
Average land 10, 0.005
Average soil 15, 0.028
Very dry ground 3, 0.0001
Average clay 10, 0.003
Mountains, rock 7, 0.0012
Arctic land 4, 0.0005
Desert 3, 0.011
Flat desert, city 2.5 to 4, 0.00022

Polar ice 3, 0.00003
Polar water 4, 0.001

Ref. Quartz 5, 1x10E-17
Ref. Free space 1,0

My understanding: mu-r=1.

Some of these come from old CCIR 527-1, Earth Classification Rec.
Others from odd sources. Need to interpret carefully.

For conversion of old emu units, 5000x10E-14 emu = 5 mho/meter.

Regards

dan bathker

cc: If any NEC-LIST members disagree on any of these, please let us
all know.

At 01:41 PM 5/19/2000 -0400, Ed Troy wrote:
>I am looking to perform a strange simulation. I need to model the
>propagation from one underground room to another through a hollow
>plastic pipe in the dirt. Does anyone know of a program that will
>model such a situation? I don't believe NEC will, but I could be
>wrong. Maybe it will if I have the correct version? It is very similar
>to a waveguide problem, but the walls of the waveguide consist of
>plastic and dirt, rather than metal. Also, does anyone know a
>reference for the electrical characteristics of dirt, such as
>dielectric constant, permeability, permittivity, etc?

Dan Bathker
Received on Wed May 24 2000 - 06:37:28 EDT