ISO 9459-1:1993 ソーラー暖房—家庭用給湯システム—パート1：屋内試験方法を使用した性能評価手順 | ページ 6

3.1

absorber

That part of a collector that receives radiant energy and transforms it into thermal energy.

3.2

accuracy

Ability of an instrument to indicate the true value of the measured physical quantity.

3.3

ambient air

Air in the space (either indoors or outdoors) surrounding the thermal energy storage device or solar collectors, whichever is applicable.

3.4

angle of incidence (of direct solar radiation)

Angle between the solar radiation beam and the outward-drawn normal from the plane considered.

3.5

aperture area

Of a solar thermal collector, maximum projected area through which the unconcentrated solar radiation is admitted.

Note 1 to entry: For concentrating collectors, the gross aperture area includes any area of the reflector or refractor shaded by the receiver and its supports and including gaps between reflector segments within a collector module. Net aperture area, sometimes called effective aperture area, excludes any shaded area or gaps between reflector segments.

3.6

aperture plane

Plane at or above the solar collector through which the unconcentrated solar radiation is admitted.

3.7

area, gross collector

Maximum projected area of a completed solar collector module, exclusive of integral means of mounting and connecting fluid conduits. For an array of collectors, including devices such as evacuated tube or concentrating collectors, gross area includes the entire area of the array.

3.8

auxiliary energy

Energy provided by an auxiliary thermal (heat) source.

3.9

auxiliary thermal (heat) source

Source of thermal energy, other than solar, used to supplement the output provided by the solar energy system; usually in the form of electrical resistance heat or thermal energy derived from combustion of fossil fuels.

3.10

collector, solar

solar thermal collector

Device designed to absorb radiant energy and to transfer the thermal energy so gained to a fluid passing through it.

3.11

collector, concentrating

Solar collector that uses reflectors, lenses or other optical elements to redirect and concentrate the solar radiation passing through the aperture onto an absorber of which the surface area may be smaller than the aperture area.

3.12

collector, flat-plate

Non-concentrating solar collector in which the absorbing surface is essentially planar.

3.13

collector loop

Continuous path followed by the primary heat transfer fluid in a solar energy system.

3.14

collector loop heater

Heater installed within the collector loop when testing the solar domestic water heating system with a non-irradiated array.

3.15

collector tilt angle

Lower angle between the aperture plane of a solar collector and the horizontal plane.

3.16

control

Device for regulation of the solar thermal system or component in normal operation; can be manual or automatic.

3.17

direct irradiance

Irradiance produced by direct radiation on a given plane.

3.18

direct solar radiation

Radiation received from a small solid angle centred on the sun's disc, on a given plane.

Note 1 to entry: In general direct solar radiation is measured by instruments with field-of-view angles of up to 15°. Therefore a part of the scattered radiation around the sun's disc (circumsolar radiation) is included. More than 99 % of the direct solar radiation on the earth's surface is contained within the wavelength range from 0,3 μm to 3,0 μm.

3.19

domestic

For use in residential and small commercial buildings.

3.20

draw rate

water draw rate

Rate at which hot water is withdrawn from a system at a specified time.

3.21

equivalent length

Length of a straight section of pipe or duct causing the same pressure drop as that which actually occurs within the system at the same flowrate.

3.22

fluid transport

Transfer of air, water or other fluid between components of the system.

3.23

heat exchanger

Device specifically designed to transfer heat between two physically separated fluids. Heat exchangers may have either single or double walls.

3.24

heat transfer fluid

Fluid that is used to transfer thermal energy between components in a system.

3.25

irradiance

Power density of radiation incident on a surface, i.e. the radiant flux incident on a surface divided by the area of that surface, or the rate at which radiant energy is incident on a surface per unit area of that surface.

Note 1 to entry: Solar irradiance is often termed"incident solar radiation intensity","instantaneous insolation", or"incident radiant flux density"; the use of these terms is deprecated.

3.26

load

Daily system hot water load defined as the product of the mass, specific heat and temperature increase of the water as it passes through the solar hot water system.

3.27

potable

Suitable for human consumption; drinkable.

3.28

precision

Measure of the closeness of agreement among repeated measurements of the same physical quantity.

3.29

preheating

See solar preheat system [5.1 b)].

3.30

pyranometer

Radiometer for measuring the irradiance on a plane receiver surface which results from the radiant fluxes incident from the hemisphere above within the wavelength range 0,3 μm to 3 μm.

Note 1 to entry: The spectral range given represents roughly the spectral range of solar radiation (also called solar or shortwave range) at the ground and is only nominal. Depending on the material used for the domes which protect the receiver surface of a pyranometer, the spectral limits of its responsivity approximate to the limits mentioned above.

3.31

pyrgeometer

Instrument for determining the irradiance on a plane receiving surface which results from the radiant fluxes incident from the hemisphere above within the approximate wavelength range 4 μm to 50 μm.

Note 1 to entry: The given spectral range is nearly identical with that of so-called terrestrial radiation or long-wave radiation, and is only nominal. Depending on the material used for the domes which protect the receiving surface of a pyrgeometer, the spectral limits of its responsivity approximate to the limits mentioned above.

3.32

pyrheliometer

Radiometer for measuring direct (solar) irradiance which results from the radiant fluxes incident from a well-defined solid angle whose axis is perpendicular to the plane receiver surface.

Note 1 to entry: According to this definition pyrheliometers are applied to the measurement of direct solar irradiance at normal incidence. The field-of-view angle of pyrheliometers ranges typically from 5° to 10°.

3.33

solar energy

Energy emitted by the sun in the form of electromagnetic radiation (primarily in the wavelength range 0,3 μm to 3 μm), or any energy made available by the reception and conversion of solar radiation.

3.34

solar contribution

Ratio of the energy supplied by the solar part of a system to the total load of the system.

3.35

solar noon

Local time of day, for any given location, when the sun is at its highest altitude for that day, i.e. the time when the sun crosses the observer's meridian.

3.36

solar radiation

Radiation emitted by the sun, practically all of which is incident at the earth's surface at wavelengths less than 3 μm; often termed"short-wave radiation".

3.37

solar irradiance simulator

Artificial source of radiant energy simulating solar radiation (usually an electric lamp or an array of such lamps).

3.38

solar storage capacity

Quantity of sensible heat that can be stored per unit volume of store for every degree of temperature change.

3.39

solar hot water system

Complete assembly of subsystems and components necessary to convert solar energy into thermal energy for the heating of water; may include an auxiliary heat source.

3.40

standard air

Air weighing 1,204 kg/m³ which approximates dry air at a temperature of 20 °C and a barometric pressure of 101,325 kPa.

3.41

standard barometric pressure

Barometric pressure of 101,325 kPa at 0 °C.

3.42

storage device (thermal)

Container(s) plus all contents of the container(s) used for storing thermal energy.

Note 1 to entry: The transfer fluid and accessories such as heat exchangers, flow switching devices, valves and baffles which are firmly fixed to the thermal storage container(s) are considered a part of the storage device.

3.43

storage tank volumetric capacity

Measured volume of the fluid in the tank when full.

3.44

temperature, ambient air

Temperature of the air surrounding the thermal energy storage device or solar collectors being tested.

3.45

time constant

Time required for a first-order system to change output by 63,2 % of its final change in output following a step change in input.

3.46

thermopile

Set of thermocouples wired consistently in series or parallel to measure small or average temperature differences.