Table 2. Suggested input values for the NWT input file

Input variable name

Default values

Range

Iteration Control

HEADTOL

1×10-4 (L)*

–

FLUXTOL

500 (L3/T)*

–

MAXITEROUT

100

10–2,000

Dry Cell Tolerance

THICKFACT

0.00001

1×10-6-1

NWT Options

LINMETH

1

1 or 2

IPRNWT

0

0 or 2

IBOTAV

0**

0 or 1

Under relaxation Input

Model Complexity

Simple

Moderate

Complex

DBDTHETA

0.97

0.90

0.85

0–1

DBDKAPPA

0.0001

0.00001

0.00001

0–1

DBDGAMMA

0.0

0.0

0.0

0–1

MOMFACT

0.0

0.1

0.1

0–1

Residual Control

Model Complexity

Simple

Moderate

Complex

BACKFLAG

0***

0

1

0 or 1

MAXBACKITER

20

20

50

1–100

BACKTOL

1.5

1.1

1.1

1–2

BACKREDUCE

0.97

0.9

0.7

0.05–0.99

Linear Solution Control and Options for GMRES

Model Complexity

Simple

Moderate

Complex

MAXITINNER

50

50

50

25–1,000

ILUMETHOD

2

2

2

1 or 2

LEVFILL

1

1

1

5–10 for ILUMETHOD=1

0–2 for ILUMETHOD=2

STOPTOL

1×10-10

1×10-10

1×10-10

1×10-8-1×10-12

MSDR

5

10

15

5–20

Linear Solution Control and Options for χMD

Model Complexity

Simple

Moderate

Complex

IACL

1

1

2

0,1, or 2

NORDER

0

0

0

0,1, or 2

LEVEL

1

1

15

1–10

NORTH

5

10

1

4-10 for Orthomin

2 otherwise

IREDSYS

1

1

1

0 or 1

RRCTOLS

0.0

0.0

0.0

0–0.0001

IDROPTOL

1

1

1

0 or 1

EPSRN

5×10-3

5×10-3

1×10-3

5×10-5-1×10-3

HCLOSEXMD

1×10-3

1×10-3

1×10-4

1×10-3-1×10-5

MXITERXMD

50

100

200

25–1,000