Heat transfer fluid comprising difluoromethane and carbon dioxide

摘要

Disclosed are heat transfer fluids which possess a highly desirable and unexpectedly superior combination of properties, and heat transfer systems and methods based on these fluids. The heat transfer fluid comprises at least 30 percent on a molar basis of carbon dioxide (CO<Sub>2</Sub>) and hydrofluorocarbon of a type effective and in an amount sufficient to provide a non- flammable fluid having a coefficient of performance of at least 1.90.