Fluid mechanics is a branch of mechanics, it is mainly to study the interaction and flow of the law of the stationary state of the fluid itself and the state of motion, and fluid and solid boundary wall of the relative motion. Fluid mechanics, the most studied fluid is water and air. It is mainly based on Newton's laws of motion and mass conservation law, often also used in the thermodynamic knowledge, sometimes used in the basic laws of macroscopic electrodynamics, the constitutive equations and physics, the chemical basis of knowledge.
1738 Bernoulli published his monograph, the first term of the hydrodynamic and as the title; 1880 before and after the term of the aerodynamics; after 1935, it summarizes the knowledge of these two areas, the establishment of unified system, collectively known as fluid mechanics.
In addition to water and air, fluid refers to as a turbine working medium of steam, lubricating oil, oil in the ground, river sand, blood, ultra-high pressure under the metal and burning a complex composition of the gas under high temperature conditions plasma and so on.
Until the 15th century, Italy, Finch's book before it comes to waves, pipe flow, hydraulic machinery, birds fly principle; 17th century, Pascal clarify the concept of static fluid pressure. But fluid mechanics, especially fluid dynamics as a rigorous science, but it is that classical mechanics, speed, acceleration, force, flow field concept, as well as quality, momentum, energy, three conservation laws of laid before gradually formed the.