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Water Flow Test
A water flow test, also known as a hydrant flow test, is a way to measure the water supply available at a building site, usually for the purposes of installing a water based fire protection system (fire sprinkler system). The most common test involves measuring the flow of water flowing out of a municipal fire hydrant (measured in litres or gallons per minute) while recording how much the water pressure has dropped (from no water flow to test flow). When the results are collected carefully, formulas can be applied to figure the varying pressure(s) that will be available when different amounts of water flow are used from the same source. A process to perform a water flow test is explained in the model fire codes as published by NFPA (National Fire Protection Association). If a water supply source is considered weak compared to what is required by the sprinkler system design hydraulic calculation, the water pressure can be boosted by means of a fire pump. General testing procedure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire Sprinkler System
A fire sprinkler system is an active fire protection method, consisting of a water supply system, providing adequate pressure and flowrate to a water distribution piping system, onto which fire sprinklers are connected. Although historically only used in factories and large commercial buildings, systems for homes and small buildings are now available at a cost-effective price. Fire sprinkler systems are extensively used worldwide, with over 40 million sprinkler heads fitted each year. Even though Fire Sprinkler Systems are a Life Saving System and are not designed to protect the building, 96% of buildings that had fires and were completely protected by fire sprinkler systems were controlled by the fire sprinklers alone. History Leonardo da Vinci designed a sprinkler system in the 15th century. Leonardo automated his patron's kitchen with a super-oven and a system of conveyor belts. In a comedy of errors, everything went wrong during a huge banquet, and a fire broke out. "Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Fire Protection Association
The National Fire Protection Association (NFPA) is an international nonprofit organization devoted to eliminating death, injury, property and economic loss due to fire, electrical and related hazards. As of 2018, the NFPA claims to have 50,000 members and 9,000 volunteers working with the organization through its 250 technical committees. History In 1895, a Committee on Automatic Sprinkler Protection was formed in Massachusetts by men affiliated with several fire insurance companies and a pipe manufacturer to develop a uniform standard for the design and installation of fire sprinkler systems. At the time, there were nine such standards in effect within of Boston, Massachusetts, and such diversity was causing great difficulties for plumbers working in the New England region. The next year, the committee published its initial report on a uniform standard, and went on to form the NFPA in late 1896. The committee's initial report evolved into NFPA 13, ''Standard for the Installat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydraulic Calculation
Water transportation and distribution networks require hydraulic calculations to determination the flowrate and pressure characteristics at one or several consumption points and the water supply flowrate and pressures needed to meet the design requirements. In the context of fire safety, hydraulic calculations are used to determine the flow of an extinguishing medium through a piping network and through discharge devices (e.g., nozzles, sprinklers) to control, suppress, or extinguish fires. Fire safety calculations Hydraulic calculations verify that the water flowrate (or water mixed with additives like firefighting foam concentrate) through piping networks for the purpose of suppressing or extinguishing a fire will be sufficient to meet design objectives. The hydraulic calculation procedure is defined in the applicable reference model codes such as that published by the US-based National Fire Protection Association (NFPA), or the EN 12845 standard, ''Fixed firefighting system †... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fire Pump
A fire pump usually refers to a pressure-increasing component of the water supply for fixed-place fire suppression systems such as fire sprinklers, standpipes, and foam systems. Fire pumps are also a critical component integrated into fire trucks and fire boats, and serve a similar purpose boosting water supplies for firefighting hose operations. Fire pumps are used to increase the pressure of water sourced from a municipal underground water supply piping network, or a static supply (e.g., tank, reservoir, lake). A fire pump is a centrifugal- or positive displacement- pump that has been tested and listed by a third-party testing and listing agency, such as UL or FM Global specifically for fire service use. The main standard that governs fire pump fixed-place installations in North America is the National Fire Protection Association's ''NFPA 20 Standard for the Installation of Stationary Fire Pumps for Fire Protection''. Fire pumps are powered most commonly by an electric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pitot Tube
A pitot ( ) tube (pitot probe) measures fluid flow velocity. It was invented by a French engineer, Henri Pitot, in the early 18th century, and was modified to its modern form in the mid-19th century by a French scientist, Henry Darcy. It is widely used to determine the airspeed of aircraft; the water speed of boats; and the flow velocity of liquids, air, and gases in industry. Theory of operation The basic pitot tube consists of a tube pointing directly into the fluid flow. As this tube contains fluid, a pressure can be measured; the moving fluid is brought to rest (stagnates) as there is no outlet to allow flow to continue. This pressure is the stagnation pressure of the fluid, also known as the total pressure or (particularly in aviation) the pitot pressure. The measured stagnation pressure cannot itself be used to determine the fluid flow velocity (airspeed in aviation). However, Bernoulli's equation states: :Stagnation pressure = static pressure + dynamic pressure Whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stagnation Pressure
In fluid dynamics, stagnation pressure is the static pressure at a stagnation point in a fluid flow.Clancy, L.J., ''Aerodynamics'', Section 3.5 At a stagnation point the fluid velocity is zero. In an incompressible flow, stagnation pressure is equal to the sum of the free-stream static pressure and the free-stream dynamic pressure. Stagnation pressure is sometimes referred to as pitot pressure because the two pressures are numerically equal. Magnitude The magnitude of stagnation pressure can be derived from Bernoulli equation for incompressible flow and no height changes. For any two points 1 and 2: :P_1 + \tfrac \rho v_1^2 = P_2 + \tfrac \rho v_2^2 The two points of interest are 1) in the freestream flow at relative speed v where the pressure is called the "static" pressure, (for example well away from an airplane moving at speed v); and 2) at a "stagnation" point where the fluid is at rest with respect to the measuring apparatus (for example at the end of a pitot tube in an ai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
