HDPsyChart Version 8 can easily change the chart style from Psychrometric Chart to
Grosvenor Humidity Chart.
The Grosvenor Humidity Chart is named after William Mason Grosvenor (1873 to 1944), Pennsylvania University Ph.D., and accompanied the document "Transactions of the American Institute of Chemical Engineers" (1908).
Click Here or on the Chart to View Large PDF
Click Here to view ASHRAE Journal Article written by Donald P. Gatley, P.E.