Fluid Mechanics Contributions

Fluid Mechanics History

• Fluid mechanics has a history of early achievements, then an intermediate era of steady discoveries in the 18th and 19th centuries.
• Ancient civilizations used knowledge to solve flow problems (e.g., sailing ships, irrigation).
• Archimedes and Hero of Alexandria laid groundwork in the 3rd century BCE.
• Quantitative information emerged, including the parallelogram law for vectors and understanding buoyancy.

Early Developments

• Improvements in flow systems like ships and water conduits occurred before the Renaissance.
• Leonardo da Vinci (1452-1519) is noted for his understanding of flow conservation and analysis. He accurately described high-drag/low-drag designs, waves, and jets/jumps.
• Edme Mariotte (1620-1684) built and used the first wind tunnel.
• Isaac Newton's (1642-1727) laws of motion and viscosity helped advance the field.

Newtonian Era

• Eighteenth-century advancements used the assumption of frictionless fluid and yielded many beautiful solutions.
• Mathematicians like Daniel Bernoulli, Leonhard Euler, Jean d'Alembert, Joseph-Louis Lagrange, and Pierre-Simon Laplace made significant contributions.
• These solutions focused on frictionless fluid, ignoring important viscosity effects, which are predominant in most engineering flows.

Hydrodynamics Development

• Realization that ideal/perfect fluid assumptions are unrealistic.
• Engineers began to develop hydraulics and rely more on experimental observations of how real fluids behave. Key figures include Chezy, Pitot, Borda, Weber, Francis, Hagen, Poiseuille, Darcy, and Manning.
• Improved understanding of water, pipe, and turbine flow.
• Late 19th century saw unification between theoretical hydrodynamics and experimental hydraulics. Key figures like William Froude and son Robert Froude advanced this effort.

Dimensional Analysis

• Laws of model testing developed, and dimensional analysis and techniques were proposed.
• Osborne Reynolds (1842-1912) is famous for his pipe experiment, notably illustrating the influence of the Reynolds number.

Viscous Flow

• Navier (1785-1836) and Stokes (1819-1903) developed Navier-Stokes equations, the governing equations for fluid flow, but they were difficult to solve for complex flows.

Boundary Layer Theory

• Ludwig Prandtl (1875-1953) introduced the crucial concept of boundary layers. The fundamental and most important and most important breakthrough.
• Boundary layer theory greatly simplified analysis for fluid flows such as air and water via simplifying the solution to two layers.
• This is a very impactful theory that greatly improves fluid mechanics.

Twentieth Century Fluid Mechanics

• Theodore von Kármán and Sir Geoffrey Taylor (along with Prandtl) further developed and advanced the science via broad based experiments.