Mazda Bongo Brawny Truck Double Cab rear

A mudflap or mud guard is used in combination with the

vehicle fender A vehicle () is a machine designed for self-propulsion, usually to transport people, cargo, or both. The term "vehicle" typically refers to land vehicles such as human-powered land vehicle, human-powered vehicles (e.g. bicycles, tricycles, velo ...

to protect the vehicle, passengers, other vehicles, and pedestrians from

mud Mud (, or Middle Dutch) is loam, silt or clay mixed with water. Mud is usually formed after rainfall or near water sources. Ancient mud deposits hardened over geological time to form sedimentary rock such as shale or mudstone (generally cal ...

and other flying

debris Debris (, ) is rubble, wreckage, ruins, litter and discarded waste, garbage/refuse/trash, scattered remains of something destroyed, or, as in geology, large rock fragments left by a melting glacier, etc. Depending on context, ''debris'' can ref ...

thrown into the air by a rotating

tire A tire (North American English) or tyre (Commonwealth English) is a ring-shaped component that surrounds a Rim (wheel), wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide Traction (engineeri ...

on a wheeled vehicle. A mudflap is typically made from a flexible material such as

rubber Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Types of polyisoprene ...

that is not easily damaged by contact with flying debris, the tire, or the

road A road is a thoroughfare used primarily for movement of traffic. Roads differ from streets, whose primary use is local access. They also differ from stroads, which combine the features of streets and roads. Most modern roads are paved. Th ...

surface. On bicycles the mudflap is called a spoiler. It helps keep the rider(s) cleaner. Mudflaps can be large rectangular sheets suspended behind the tires, or may be small molded lips below the rear of the vehicle's wheel wells. Mudflaps can be aerodynamically engineered, utilizing shaping, louvers or vents to improve airflow and to lower drag. While some flaps are plain, in the colour of rubber, many contain company

logo A logo (abbreviation of logotype; ) is a graphic mark, emblem, or symbol used to aid and promote public identification and recognition. It may be of an abstract or figurative design or include the text of the name that it represents, as in ...

s, other art or sometimes

advertisement Advertising is the practice and techniques employed to bring attention to a Product (business), product or Service (economics), service. Advertising aims to present a product or service in terms of utility, advantages, and qualities of int ...

s. One possible feature is the

mudflap girl Mudflap Girl is a silhouette of a woman with an Hourglass figure, hourglass body shape, sitting, leaning back on her hands, with her hair being blown in the wind. The image was created in the 1970s and was popularized on mudflaps. Subsequently, it ...

, a woman's

silhouette A silhouette (, ) is the image of a person, animal, object or scene represented as a solid shape of a single colour, usually black, with its edges matching the outline of the subject. The interior of a silhouette is featureless, and the silhouett ...

. In the United States, mudflap regulations vary from state to state.

Aerodynamic

Aerodynamic mudflaps are engineered with

louver A louver (American English) or louvre (Commonwealth English; American and British English spelling differences#-re, -er, see spelling differences) is a window blind or window shutter, shutter with horizontal wikt:slat, slats that are angle ...

s or ventilated slats to improve airflow, reduce sidespray, and decrease

aerodynamic drag In fluid dynamics, drag, sometimes referred to as fluid resistance, is a force acting opposite to the direction of motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers, two solid surfaces, or b ...

, in order to improve

fuel efficiency Fuel efficiency (or fuel economy) is a form of thermal efficiency, meaning the ratio of effort to result of a process that converts chemical energy, chemical potential energy contained in a carrier (fuel) into kinetic energy or Mechanical work, w ...

Supercomputing A supercomputer is a type of computer with a high level of performance as compared to a general-purpose computer. The performance of a supercomputer is commonly measured in floating-point operations per second (FLOPS) instead of million instruc ...

technology applied to the problem of

semi-trailer truck A semi-trailer truck (also known by a wide variety of other terms – see below) is the combination of a tractor unit and one or more semi-trailers to carry freight. A semi-trailer attaches to the tractor with a type of hitch called ...

drag has helped to validate such aerodynamic improvements. Traditional solid truck mudflaps can increase drag, but a study by the UT-Chattanooga SimCenter indicated slatted mudflaps can reduce drag more than 8 percent, making the truck's drag coefficient comparable to one without any mudflaps fitted.NRC Canada
2012 A further advantage of the design is the heat-venting capacity of aerodynamically optimized mudflaps. The improved airflow promotes the quick release of otherwise re-circulated water and air from the fenderwell while improving performance by cooling the tires and brakes.

References

Automotive accessories {{Automotive-part-stub

Aerodynamic

See also

References