International Commission on Irrigation & Drainage Commission Interationale des Irrigation et du Drainage

Multilingual Technical Dictionary (MTD)
<<    Browsing page 1 of 2    >>
Term No.Term Name/Term DescriptionAction
215
Confidence coefficient, or Confidence level
The measure of probability associated with a confidence interval is called `confidence coefficient` or `confidence level`......
Similar Terms
379
Thermal conductivity
img:equations//374_380_e.jpg
Similar Terms
432
Viscosity, (Dynamic viscosity)
img:equations//430_433_e.jpg
Similar Terms
800
Pluviometric coefficient, or Hyetal coefficient
The ratio of the actual precipitation in a month to what would have fallen had the rainfall been uniformly distributed throughout the year......
Similar Terms
895
Pan coefficient, or Conversion coefficient
The ratio of evaporation from a large body of water to that from a pan.
Similar Terms
910
Coefficient of permeability, Hydraulic conductivity, Coefficient of conductivity, Unit of permeability, Transmission constant, Coefficient of transmission
1   The rate at which groundwater flows through a soil in response to a given hydraulic head. 2   The rate of flow of a fluid through a unit cross section of a porous mass under a unit hydraulic gradient, at a specified temperature. 3 - See 6497......
Similar Terms
1212
Mean velocity, Average velocity, Overall mean velocity
The velocity at a given section or reach of a stream obtained by dividing the discharge of the stream by the cross-sectional area at that section. .....
Similar Terms
1387
Eddy
A current running back, contrary to the main stream, thus causing a curvilinear motion.
Similar Terms
1388
Confined eddy
An eddy confined due to contact with a structure, such as a guide bank.
Similar Terms
1389
Free eddy
An eddy which is free to move away from bypassing contact with a structure, such as a guide bank which otherwise hinders its uprise......
Similar Terms
1650
Mechanical analysis, or Physical analysis
The process of separating a soil by mechanical means into various sized particle groups according to an effective diameter......
Similar Terms
1766
Exchange complex, or Absorbing complex
The surface-active constituents of soil (both inorganic and organic) that are capable of cation exchange.
Similar Terms
1768
Exchangeable
Describes ions capable of replacement in the exchange (absorbing complex).
Similar Terms
1769
Ion exchange, Cation exchange, or Anion exchange
The replacement in a colloidal system of an ion by another with a charge of the same sign. Cation exchange refers to the interchange of positively charged ions (cations) and anion exchange to the replacement of negatively charged ions (anions) by other anions......
Similar Terms
1770
Exchange capacity, Cation exchange capacity, Base exchange capacity, or Saturation capacity
The total cation exchange, usually expressed as milliequivalents per 100 grams. Measured value of cation exchange capacity depends somewhat on the method used for the determination......
Similar Terms
1786
Exchangeable-sodium percentage (ESP)
The degree of saturation of the soil exchange complex with sodium. It may be calculated by the formula :
Similar Terms
1788
Exchange acidity
Acidity produced by treating soil with a solution of a neutral salt.
Similar Terms
1789
Exchangeable acidity or Potential acidity
H+ ions held in reserve
Similar Terms
1818
Permanent wilting percentage, Wilting percentage, Wilting coefficient, or Permanent wilting point
The moisture content of the soil, expressed as a percentage of the dry mass when the leaves of a plant growing in the soil first undergo a permanent reduction in their moisture content. The soil water content at which plants will permanently wilt......
Similar Terms
2791
Mechanically induced water seal
Water seal formed by mechanical means such as (i) by installing an air pump to suck out air from the siphon (ii) by installing a flexible steel plate at the crest and projecting into the siphon duct (illustrated)......
Similar Terms
3065
Coefficient of viscosity, Absolute viscosity, or Dynamic viscosity
A numerical factor that is a measure of the internal resistance of a fluid to flow; the greater the resistance to flow the larger the coefficient. It is equal to the shearing force in dynes per square centimetre transmitted from one fluid plane to another parallel plane 1 cm distant, and is generated by a difference in fluid velocities in the two p.....
Similar Terms
3068
Eddy viscosity, Mechanical velocity, Exchange coefficient, or Eddy conductivity
Analogous to the dynamic viscosity, but depends upon the Reynolds number and other parameters. Referred to by various writers as the `mechanical velocity`, `exchange coefficient` and `eddy conductivity`......
Similar Terms
3075
Shear velocity, Shear stress velocity, Prandtl`s shear velocity, Prandtl`s friction velocity, or Friction velocity
Prandtl’s well-known parameter of turbulence theory which is equal to ∑t0 / ρ, where t0 is the boundary shear or drag and ρ is the fluid density......
Similar Terms
3083
Roughness coefficient, Coefficient of roughness, Rugosity factor, or Coefficient of retardance, Resistance coefficient.
Any of several factors used in equations for open or closed conduit flows to represent the retarding effects of channel boundary resistance on the fluid flow : For examples see 3079, 3080 and 3081......
Similar Terms
3098
Terminal velocity, or Fall velocity
Final velocity of falling particles of a specified sediment grade in still water at a specified temperature.
Similar Terms
<<    Browsing page 1 of 2    >>