Ads
related to: boiler flow rate explained
Search results
Results From The WOW.Com Content Network
Boiler turndown ratio is the ratio of maximum heat output to the minimum level of heat output at which the boiler will operate efficiently or controllably. Many boilers are designed to operate at a variety of output levels. As the desired temperature/pressure point is approached, the heat source is progressively turned down.
The actual vapor power cycle differs from the ideal Rankine cycle because of irreversibilities in the inherent components caused by fluid friction and heat loss to the surroundings; fluid friction causes pressure drops in the boiler, the condenser, and the piping between the components, and as a result the steam leaves the boiler at a lower ...
A boiler is a closed vessel in which fluid (generally water) is heated. The fluid does not necessarily boil. The heated or vaporized fluid exits the boiler for use in various processes or heating applications, [1] [page needed] [2] [page needed] including water heating, central heating, boiler-based power generation, cooking, and sanitation.
A forced circulation boiler is a boiler where a pump is used to circulate water inside the boiler. This differs from a natural circulation boiler which relies on current density to circulate water inside the boiler. In some forced circulation boilers, the water is circulated at twenty times the rate of evaporation. [1]
Combination boilers are rated by the DHW flow rate. The kW ratings for domestic units are typically 24 kW to 54 kW, giving approximate flow rates of 9 to 23 litres (2.4 to 6.1 US gal) per minute. Larger units are used in commercial and institutional applications, or for multiple-unit dwellings.
A boiler incorporates a firebox or furnace in order to burn the fuel and generate heat. The generated heat is transferred to water to make steam, the process of boiling. This produces saturated steam at a rate which can vary according to the pressure above the boiling water. The higher the furnace temperature, the faster the steam production.
In a cross-flow, in which one system, usually the heat sink, has the same nominal temperature at all points on the heat transfer surface, a similar relation between exchanged heat and LMTD holds, but with a correction factor. A correction factor is also required for other more complex geometries, such as a shell and tube exchanger with baffles.
Where hot-water space heating boilers are installed, domestic hot water cylinders are usually heated indirectly by primary water from the boiler, or by an electric immersion heater (often as backup to the boiler). In the UK these vessels are called indirect cylinders and direct cylinders, respectively. Additionally, if these cylinders form part ...