Michael Max Munk
Encyclopedia
Max Michael Munk was a German aerospace engineer who for National Advisory Committee for Aeronautics
(NACA) in the 1920s and made contributions to the design of airfoil
s.
Munk earned an engineering degree from the Hanover Polytechnic School in 1914, and earned doctorates in both physics
and mathematics
from the University of Göttingen in 1917. After World War I, NACA
(National Advisory Committee for Aeronautics, later to become NASA) brought Munk to the United States. President Woodrow Wilson
signed orders allowing Munk to come to the United States and work in government. These orders were required since Germany was a recent enemy and Munk had worked briefly for the German Navy.
Munk began work at NACA in 1920 and proposed building the new Variable-Density Wind Tunnel
(VDT) which went into operation in 1922. Munk published more than 40 articles with NACA.
Munk is best known for his development of thin airfoil theory, a means of modelling the behaviour of airfoil
s by separating their shape (the "mean camber line""Mean camber line" is a conceptual curved line drawn through the mean centre of the airfoil, equally spaced from the upper and lower surfaces) and their varying thicknessDistribution of thickness across the chord
, i.e. from front to back of the airfoil. This allows separate, and simpler, techniques to model each behaviour. Lift
may be assumed to depend on the camber (and angle of attack
) alone, and could be modelled by the numerical techniques of the period. Drag
depends on the thickness and requires an understanding of viscous flow, which was beyond contemporary capabilities. The thin airflow technique was introduced in 1922 and remained the major theoretical design technique until the development of laminar flow
airfoils in the 1930s.
National Advisory Committee for Aeronautics
The National Advisory Committee for Aeronautics was a U.S. federal agency founded on March 3, 1915 to undertake, promote, and institutionalize aeronautical research. On October 1, 1958 the agency was dissolved, and its assets and personnel transferred to the newly created National Aeronautics and...
(NACA) in the 1920s and made contributions to the design of airfoil
Airfoil
An airfoil or aerofoil is the shape of a wing or blade or sail as seen in cross-section....
s.
Munk earned an engineering degree from the Hanover Polytechnic School in 1914, and earned doctorates in both physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
and mathematics
Mathematics
Mathematics is the study of quantity, space, structure, and change. Mathematicians seek out patterns and formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proofs, which are arguments sufficient to convince other mathematicians of their validity...
from the University of Göttingen in 1917. After World War I, NACA
NACA
- Organizations :* National Advisory Committee for Aeronautics, the forerunner of the U.S. federal agency NASA* National Association for Campus Activities, an organization for programmers of university and college activities...
(National Advisory Committee for Aeronautics, later to become NASA) brought Munk to the United States. President Woodrow Wilson
Woodrow Wilson
Thomas Woodrow Wilson was the 28th President of the United States, from 1913 to 1921. A leader of the Progressive Movement, he served as President of Princeton University from 1902 to 1910, and then as the Governor of New Jersey from 1911 to 1913...
signed orders allowing Munk to come to the United States and work in government. These orders were required since Germany was a recent enemy and Munk had worked briefly for the German Navy.
Munk began work at NACA in 1920 and proposed building the new Variable-Density Wind Tunnel
Wind tunnel
A wind tunnel is a research tool used in aerodynamic research to study the effects of air moving past solid objects.-Theory of operation:Wind tunnels were first proposed as a means of studying vehicles in free flight...
(VDT) which went into operation in 1922. Munk published more than 40 articles with NACA.
Munk is best known for his development of thin airfoil theory, a means of modelling the behaviour of airfoil
Airfoil
An airfoil or aerofoil is the shape of a wing or blade or sail as seen in cross-section....
s by separating their shape (the "mean camber line""Mean camber line" is a conceptual curved line drawn through the mean centre of the airfoil, equally spaced from the upper and lower surfaces) and their varying thicknessDistribution of thickness across the chord
Chord (aircraft)
In aeronautics, chord refers to the imaginary straight line joining the trailing edge and the center of curvature of the leading edge of the cross-section of an airfoil...
, i.e. from front to back of the airfoil. This allows separate, and simpler, techniques to model each behaviour. Lift
Lift (force)
A fluid flowing past the surface of a body exerts a surface force on it. Lift is the component of this force that is perpendicular to the oncoming flow direction. It contrasts with the drag force, which is the component of the surface force parallel to the flow direction...
may be assumed to depend on the camber (and angle of attack
Angle of attack
Angle of attack is a term used in fluid dynamics to describe the angle between a reference line on a lifting body and the vector representing the relative motion between the lifting body and the fluid through which it is moving...
) alone, and could be modelled by the numerical techniques of the period. Drag
Lift-induced drag
In aerodynamics, lift-induced drag, induced drag, vortex drag, or sometimes drag due to lift, is a drag force that occurs whenever a moving object redirects the airflow coming at it. This drag force occurs in airplanes due to wings or a lifting body redirecting air to cause lift and also in cars...
depends on the thickness and requires an understanding of viscous flow, which was beyond contemporary capabilities. The thin airflow technique was introduced in 1922 and remained the major theoretical design technique until the development of laminar flow
Laminar flow
Laminar flow, sometimes known as streamline flow, occurs when a fluid flows in parallel layers, with no disruption between the layers. At low velocities the fluid tends to flow without lateral mixing, and adjacent layers slide past one another like playing cards. There are no cross currents...
airfoils in the 1930s.