Expert Witness Services

District Heating and Cooling

Geothermal Heat Pumps

Heat Transfer in Soil Systems

Cold Regions Heat Transfer






Gary Phetteplace has acted as an expert witness on several lawsuits involving allegations of thermal damage to adjacent utilities from buried steam pipelines. 

Chart of Soil Temperatures by depth and day of year

Soil temperatures as a function of depth calculated by GWA Research LLC for a specific climate, soil type, and moisture content. 


Heat Transfer in Soil Systems


Gary Phetteplace has been working on heat transfer problems in soils, primarily associated with buried utilities, since 1978.  His work has included development of finite element models for conduction heat transfer as well as many programs where field measurements were made for verification of computational procedures.  He has extensive experience in instrumenting all types of buried heat distribution systems (direct buried, trench type, and utilidor/tunnel) using steam and high/medium/low temperature hot water as the carrier fluid.  Gary Phetteplace has also conducted work in the area of frost shielding of buried water and sewer pipelines using rigid extruded polystyrene insulation.  Gary Phetteplace developed the consistent set of heat transfer relations that are contained in Chapter 11 - District Heating and Cooling of the 2008 (and many past versions as well) of the ASHRAE HVAC Systems and Equipment Handbook.

© 2016 GWA Research, LLC         December 28, 2016