New Features - GLHEPro

 

New features for Version 5.0

GLHEPro Version 5.0 was released in the April of 2016 and has many new features, incorporating many years of research. This research has resulted in nearly 100 peer-reviewed papers and book chapters and has also led to many new features in GLHEPro. GLHEPro Version 5.0 has significantly expanded simulation and sizing options.

Significant new features include:

  • User-specified borehole configurations for up to 30 boreholes – these can be vertical or inclined and irregularly placed. (Page 2.)

  • Horizontal ground heat exchangers. (Page 3)

  • Hourly simulations of GSHP systems. (Page 3.)

  • Worldwide database of time- and depth-varying ground temperatures. (Page 4.)

  • Hourly simulations of standing column wells.

  • More detailed borehole model can account for short circuiting resistance and groundwater-filled boreholes.

  • Improved flexibility in the hybrid system sizing feature.

Download New Features PDF

Free-Placement Finite Line Source Model: Inclined Boreholes and More!

For ground heat exchangers with up to 30 boreholes, users can specify their own configurations.  Possibilities include:

  • Irregular borehole layouts

  • Inclined boreholes

  • Boreholes with different depths

  • Horizontally-drilled boreholes

12 boreholes arranged in a circle inclined outwards at 30°, top view.

Two boreholes with significantly different depths.

12 boreholes arranged in a circle inclined outwards at 30°, front view.

A horizontally-drilled borehole.

Horizontal Ground Heat Exchangers

Two-tube and four-tube horizontal ground heat exchangers and slinky heat exchangers can be simulated and designed.

Two-tube horizontal ground heat exchanger.

Slinky heat exchanger.

 

Hourly Simulations

All systems of vertical and inclined boreholes can use an hourly simulation in GLHEPro.  The length of the simulation is limited only by the number of hourly loads you can supply.  The figure below shows a comparison of the temperature responses for a monthly simulation to the hourly simulation options.

Ground Temperature Database

 

A new undisturbed ground temperature database has temperature profiles for 4,112 global locations!

Select ground temperature by location, longitude/latitude, or specify a constant

Depth vs. Temperature on March 14th

Annual Temperature Profile at a depth of 30 ft.

Validation

Yes, but does it work?  We believe GLHEPRO Version 4.0 is the only ground heat exchanger design software for which peer-reviewed validations1 of the sizing algorithm against monitored systems have been published.  GLHEPro Version 5.0 has been validated against four monitored systems located in three different countries.  The systems have between 3 and 56 boreholes.  The approach taken was to use GLHEPro to size existing systems, using the measured loads on the ground heat exchanger as inputs and the measured minimum and maximum heat pump entering fluid temperatures as the design limits.  Compared to the actual ground heat exchangers, GLHEPRo oversized between 2 and 11%, with an average value of 6%.  This is illustrated in the figure below, where both the library g-functions and the new Free Placement Finite Line Source g-functions were used.   The error bars represent the effects of the uncertainties in the inputs on the predicted size.  Since GLHEPRO does not account for the horizontal connecting piping, a small amount of oversizing is expected.  The journal paper1 that reported on the GLHEPro Version 4.0 validation also showed that the ASHRAE handbook method could significantly oversize the ground heat exchangers for these same cases.

1Cullin, J. R., Spitler, J. D., Montagud, C., Ruiz-Calvo, F., Rees, S. J., Naicker, S. S., Konečný, P. and Southard, L. E. 2015. Validation of vertical ground heat exchanger design methodologies, Science and Technology for the Built Environment, 21:2, 137-149

 

New features for Past Versions

 

Version 4.1

  • Updated Installation program solves installation errors

  • GLHEPro will now run when the Regional/Language Settings use a “,” as a decimal separator without having to change system settings.

  • Displays Reynolds number during resistance calculations.

  • Can now paste new heat pump data into Add heat pump form.

  • 361 new heat pump models have been implemented bringing the current total to 1202.

Version 4.0

  • Capability to model rectangular borefields up to 900 boreholes.

  • Sizing of ground loop heat exchanger and supplemental heat source/sink as part of a hybrid ground source heat pump system.

  • More accurate calculation of borehole thermal resistance, including thermal mass effects.

  • Heat pump database has been greatly expanded.

Revamped fluid property routines. The working fluid can now be specified in terms of composition and concentration.

Addition of double U-tube

Addition of concentric tube heat exchangers

Marked improvement of output reporting. Users can specify what information is reported, and have the option of creating a Microsoft Excel-compatible .CSV file.

International ground temperatures are available for several locations, and users may enter additional locations.