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The gas-cooling throttling process is commonly exploited in refrigeration processes such as liquefiers in air separation industrial process. [7] [8] In hydraulics, the warming effect from Joule–Thomson throttling can be used to find internally leaking valves as these will produce heat which can be detected by thermocouple or thermal-imaging ...
This is true for all enthalpies of formation. The standard enthalpy of formation is measured in units of energy per amount of substance, usually stated in kilojoule per mole (kJ mol −1), but also in kilocalorie per mole, joule per mole or kilocalorie per gram (any combination of these units conforming to the energy per mass or amount guideline).
Superheated steam was widely used in main line steam locomotives. Saturated steam has three main disadvantages in a steam engine: it contains small droplets of water which have to be periodically drained from the cylinders; being precisely at the boiling point of water for the boiler pressure in use, it inevitably condenses to some extent in the steam pipes and cylinders outside the boiler ...
Direct electric resistance tank water heaters are not included in the Energy Star program; however, the Energy Star program does include electric heat pump units with energy factors of 200% or higher. Tankless gas water heaters (as of 2015) must have an energy factor of 90% or higher for Energy Star qualification.
There are three main categories for water temperature controlling devices: Heat Source, Group Control, and Point-of-Use. Heat Source. These are used with central heating systems that use water as a medium. Tempering valves for use on hot water heat distribution systems; High flow rates suitable for use in under floor (radiant) heating applications
Electric heating can either be purely resistance-type heating or make use of a heat pump system to take advantage of low-grade heat in the air or ground. A district heating system uses centrally located boilers or water heaters and circulates heat energy to individual customers by circulating hot water or steam. This has the advantage of a ...
An air release valve on an elevated section of a large diameter lavender-colored pipe. A working system should not generate further trapped gas. Air may be drawn in if there is a small leak, or dissolved air in make-up water may come out of solution, but this generally indicates a system leak if new water is needing to be added.
Since most air-conditioning and water distribution systems only reach peak load for limited periods, energy is wasted by continually running the pumps at a fixed speed. In variable-flow hydronic systems, reducing pump speed or staging of pumps with boilers and chillers to suit part-load conditions is an energy efficient method of control.