Definition: "Scheler" refers to a type of mathematical technique used in fluid dynamics, particularly for problems involving convection, with its roots centered around the work of mathematician Joseph-Louis Lagrange in the 18th century. This approach involves using a stream function, or velocity potential, which represents how a moving fluid will move through space, rather than a vector quantity like velocity itself. Scheler's technique is often used to solve problems that involve complex convection patterns and heat transfer.