Aerodynamics of Low Reynolds Number Flyers by Wei Shyy, Yongsheng Lian, Jian Tang, Dragos Viieru, Hao Liu

By Wei Shyy, Yongsheng Lian, Jian Tang, Dragos Viieru, Hao Liu

Low Reynolds quantity aerodynamics is necessary to a couple of normal and man-made flyers. Birds, bats, and bugs were of curiosity to biologists for years, and lively examine within the aerospace engineering neighborhood, prompted by way of curiosity in micro air automobiles (MAVs), has been expanding swiftly. the first concentration of this publication is the aerodynamics linked to mounted and flapping wings. The publication think of either organic flyers and MAVs, together with a precis of the scaling laws-which relate the aerodynamics and flight features to a flyer's sizing at the foundation of easy geometric and dynamics analyses, structural flexibility, laminar-turbulent transition, airfoil shapes, and unsteady flapping wing aerodynamics. The interaction among flapping kinematics and key dimensionless parameters similar to the Reynolds quantity, Strouhal quantity, and decreased frequency is highlighted. many of the unsteady elevate enhancement mechanisms also are addressed, together with modern vortex, swift pitch-up and rotational stream, wake catch, and clap-and-fling.

Show description

Read Online or Download Aerodynamics of Low Reynolds Number Flyers PDF

Best aeronautics & astronautics books

Designing And Executing Strategy in Aviation Management

"Designing and Executing approach in Aviation administration" is designed to supply an intensely functional advisor to this significantly vital subject. accomplished in assurance and easy-to-read widespread, it permits either execs and scholars to appreciate the foundations and practicalities of crafting and executing company suggestions with an aviation context.

German Rocketeers in the Heart of Dixie: Making Sense of the Nazi Past during the Civil Rights Era

This thought-provoking examine through historian Monique Laney makes a speciality of the U. S. government–assisted integration of German rocket experts and their households right into a small southern group quickly after international struggle II. In 1950, Wernher von Braun and his staff of rocket specialists relocated to Huntsville, Alabama, a city that may have fun the staff, regardless of their crucial position within the fresh Nazi struggle attempt, for his or her contributions to the U.

X-Planes at Edwards

Todays scorching new prototypes! discover the X-planes at Edwards Air strength Base, attempt website for the worlds complex army fighter prototypes. This wide colour picture assortment offers complete info of the planes, from the times while Chuck Yeager first broke the sound barrier to todays most popular fighter prototypes, the YF-22 and YF-23.

Extra resources for Aerodynamics of Low Reynolds Number Flyers

Example text

19. Pectoralis power as a function of flight velocity. Comparative mass-specific pectoralis power as a function of flight velocity in cockatiels, doves, and magpies. , 2003). as a flyer becomes smaller, its weight shrinks at a much faster rate, meaning that it can carry very little “fuel” and has to resupply frequently. Birds, bats, and insects apply different flapping patterns in hovering and forward flight to generate lift and thrust. Typically, in slow forward flight the reduced frequency and wing-beat amplitude tend to be high, resulting in highly unsteady flow structures.

Laminar separation can modify the effective shape of an airfoil and consequently influence the aerodynamic performance. 2. Aerodynamic characteristics of representative airfoils. Figure plotted based on data from Lissaman (1983). The first documented experimental observation of a LSB was reported by Jones (1938). In general, under an adverse pressure gradient of sufficient magnitude, the laminar fluid flow tends to separate before becoming turbulent. After separation, the flow structure becomes increasingly irregular, and, beyond a certain threshold, it undergoes transition from laminar to turbulent.

Note that the wings are often flexed with their primaries rotated. For larger birds, which cannot rotate their wings between forward and backward strokes, the wings are extended to provide more lift during downstroke, whereas during the upstroke the wings are flexed backward to reduce drag. In general the flex is more pronounced in the slow forward flight than in fast forward flight. 11. As shown in the figure, to avoid large drag forces and negative lift forces, these birds flex their wings during the upstroke by rotating the primaries (tip feathers) to let air through.

Download PDF sample

Rated 4.23 of 5 – based on 15 votes