An optical instrument which consists of a sighting telescope mounted so that it is free to rotate around horizontal and vertical axes, with graduated scales so that the angles of rotation may be measured. Used to observe the motion of a pilot balloon.

The power required to compress a gas isothermally through a specified range of pressures.

The electromotive force generated in a circuit containing two dissimilar metals when one junction is at a temperature different from that of the other. see also thermocouple.

A unit of heat containing 100,000 British thermal units (Btu).

The point or outdoor temperature where the heating capacity of a heat pump matches the heating requirements of a building.

is an ejector used to compress waste or exhaust steam or any other gas through a moderate range of compression above atmospheric pressure.

A measure of the efficiency of converting a fuel to energy and useful work; useful work and energy output divided by higher heating value of input fuel times 100 (for percent).

Intergranular fracture of maraging steels with decreased toughness resulting from improper processing after hot working. Thermal embrittlement occurs upon heating above l095

The energy developed through the use of heat energy.

The storage of heat energy during utility off-peak times at night, for use during the next day without incurring daytime peak electric rates.

An architectural design (also known as the double envelope house), sometimes called a "house-within-a-house," that employs a double envelope with a continuous airspace of at least 6 to 12 inches on the north wall, south wall, roof, and floor, achieved by ...

Material that stores energy, although mass will also retain coolness. The thermal storage capacity of a material is a measure of the material's ability to absorb and store heat.

This designates the resistance of a material to heat conduction. The greater the R-value the larger the number.

The change in the measured transducer output caused by changes in ambient temperature. Usually expressed a percentage of full scale.

A group of coating or welding processes in which finely divided metallic or nonmetallic materials are deposited in a molten or semimolten condition to form a coating. The coating material may be in the form of powder, ceramic rod, wire, or molten material ...

A thermal storage wall is a south-facing wall that is glazed on the outside. Solar heat strikes the glazing and is absorbed into the wall, which conducts the heat into the room over time. The walls are at least 8 in thick. Generally, the thicker the wall, ...

See embrittlement.

A semiconductor which exhibits rapid and extremely large changes in resistance for relatively small changes in temperature.

An apparatus, used in studying soil temperatures, for measuring the total supply of heat during a given period.

A temperature-sensing element which converts thermal energy directly into electrical energy. In its basic form it consists of two dissimilar metallic conductors connected in a closed loop. Each junction forms a thermocouple. If one thermocouple is maintai ...