The key features of Wellwhiz are:

1. Easy to use, Windows interface.
2. Designed for modeling complex wells, such as horizontal with multiple fractures.
3. Numerical modeling, any well trajectory.
4. Multi phase oil, gas, water and polymer.
5. Non Darcy modeling in fracture and reservoir for all phases.
6. Models rock compaction.
7. Models fracture conductivity reduction with increased stress for predicting production loss for acid fracturing in soft chalk.
8. 3D Viewer, can view any property in the reservoir and well.
9. Predicts the drag forces in the fracture, from which one could deduce the likelihood of proppant flow back.

 Optimise Your Fracture Design
 Fracture Options
 Modeling Non Darcy Effects in a Fracture
 Constants in the equation
 Beta Factor as function of phase Saturation
 Determination of Beta Factor

WellWhiz will calculate the production rate of a hydrocarbon well. You have to give it various engineering parameters which are detailed in The WellWhiz data model. All the parameters are input either graphically or through windows or through standard format files.

One of WellWhiz's key features is the ability to accurately model fluid flow in natural or hydraulic fractures, including non-Darcy flow, which can account for a difference in production by a factor of up to 2 .

WellWhiz can model multiphase flow along a hydraulic fracture with realistic geometries (varying both width and height along the length), and non-Darcy effects, with fracture widths as small as 0.25" (0.5cm).

The package can model any aspect of fracture design, including calculating parameters such as post-fracture clean-up time and optimal clean-up flow rates.  Fracture face skin can also be modelled to quantify the effect of damage due to wall-building polymer frac. fluids on production.

WellWhiz can even compute the drag forces on the fracture proppant to assess proppant flow back and fracture stability at varying well conditions.  It can also be used to estimate optimum choke size to avoid proppant flowback.

A broad range of fracture options are available with WellWhiz entailing:

1. Any number of fractures.
2. Varying fracture/perforations height, to model choked fractures.
3. Angle between fracture and well trajectory plane is flexible.
4. Varying fracture length for each wing.
5. Arbitrary fracture shape using fracture profiles.

For two phase non-Darcy effects, a review of the literature suggests the following relationship:

(Krg is in mD)

Beta Correlation	Alpha	n1	n2
Greetsma	4.8 E04	0.50	5.50
Fredric & Graves-1	7.9 E10	1.60	0.404
Fredric & Graves-1	2.11 E10	1.55	1.0

The only method to quantify Beta is through laboratory tests. In previous years such data has been correlated to yield a relationship between permeability and Beta.

Beta, is a function of proppant size, fracturing fluid clean up, fracture width and reservoir fluid saturation and properties.