Mai suna da Dabbobi na Mai Ruwa?
Zama ko hakkin ruwa na gaba tana iya samun fahimta a matsayin zanga-zanga da ya faruwa a cikin gasar ruwa da kuma abubuwan da za su iya kasancewa masu hankali, misalai na shi ita ce kungiyar da, fita da kuma abubuwan da za su iya kasancewa masu hankali. Saboda haka, zama tana nufin zanga-zanga mai zurfi a cikin gasar ruwa saboda yadda ake kare da ruwa ko yadda ake kawo.
Misalai Ya faruwa a lokacin da ake kare da gasar steam da kuma a lokacin da ake koyar da gasar steam da condensate. Zama shi ne wani abu da ake faruwa daidai da lafiya da ba lafiya bane a ranar a kan mu'amala - idan muka kafa da kuma kasa fitoci mai ruwa a kan rukuni da muke so kuwa, (yadda ake kafa da kuma kasa fitoci mai ruwa zuwa kasa).
Misunderstood Concept about Water Hammer
Yawan alamomin thermo-hydraulic da ake bayar a cikin takarda suna da yawa ake sani a matsayin zama. Yadda ake faruwa ta zama suna da damar daɗi domin hakkin ruwa da kuma damar daɗi. Zama tana faruwa saboda babban hankalin da kuma amfani da kayan adawa da kuma yan sanda da ba daidai. Idan an faru zama, yadda ake cewa "yan sanda yana da kyau da kuma damar daɗi" tana da darasi.
Thermodynamic Phenomenon |
Location of Occurrence |
Water hammer |
In Steam pipes and headers |
Water Piston (unstable horizontal waves) |
Storage tank (like Deaerator) |
Flash condensation and evaporation shock |
In Deaearators |
Water induction, distortion of rotor or casing |
In Steam turbine and steam piping |
Occurrence of Water Hammer
Idan steam ya faru daga boiler, ya zama da yake zo wasu tsawon lokaci musamman har zuwa wurin da ake bukata shi (steam turbine ko kuma wani heat exchanger) da kuma a lokacin da ake zo tsawon lokaci, steam ya faru da yake rage. Saboda haka, steam a gasar ya faru da yake rage. A lokacin da ake faruwar da plant, yadda ake faruwa da condensate (da aka faruwa daga droplets na ruwa) tana da yawa, saboda dukkan system ya faruwa daga cold ko kuma cold start-up.
A lokacin da ake yi waɗannan droplets na condensate suna faruwa a cikin gasar steam network, kuma suna faruwa da slug mai ruwa mai kusa. Kamar yadda ake bayar a cikin takarda
Rage suna faruwa da droplets na ruwa. Gradually condensate strats getting build up along the length of pipe and forms solis slug. When this slug come across any obstruction like orifice, valve or a bend, then these obstruction will result is sudden halt of the solid slug unexpectedly. During this process the K.E energy of the solid slug changes to the pressure energy and the pipe network has to be cope with it.
Impact of Water Hammer
Yana da kyau a bayar da dalilai na zama a cikin kayan adawa da ake amfani da su a cikin plants. Misalai na bayar tana bayar da natijen da zama ke faru:
For Saturated steam recommended velocity is 25 to 35 meters per second
For water in a pipe network recommended velocity is 2 to 3 meters per second
Idan zama ya faru, slug na condensate tana faruwa da steam, kuma slug na ruwa tana zo da yake velocity da yake sama da steam, wanda tana da yawa da 10 da yake da velocity na ruwa. Saboda haka, zama tana da yawa da pressure mai yawa.
Factors help in avoiding water hammer
Steam system tana da yawa da kuma dynamic, saboda haka, tana da yawa a faruwa da zama. Amma, da amfani da hanyar engineering mai ban sha'awa, tana da kyau a faruwa da zama tare da amfani da:
Proper inclination should be provided in the steam lines in the direction of flow.
Steam trap installation at regular interval and that too at the lowest points. Installation of the steam trap at the lowest points ensure the removal of condensate from the system.
Pipe sagging results in formation of condensate in the piping network and may result in increasing the chances of water hammering. Thus steam pipes should be properly supported to avoid any sagging.
Standard start up procedures are required for cold start of the plant. Operators should be properly trained to take care of the openly of isolation valve slowly.
Proper sizing of the drain pockets, to ensure that the condensate should not jump or pass it easily. The purpose of drain packet should not be defeated to collect all the condensate and pass the same through the trap.
Type of reducers shall be eccentric instead of concentric reducers.
Water Hammer in Power Plants
Water hammer occurs when water, accelerated by steam pressure or a low-pressure void, is suddenly stopped by impact on a valve or fitting, such as bend or tee, or on a pipe surface. Water velocities can be much higher than the normal steam velocity in the pipe, especially when the water hammer is occurring at startup.
When these velocities are destroyed by impact, the kinetic energy in the water is converted into pressure energy, and a pressure shock is applied to the obstruction. In mild cases, there is noise and perhaps movement of the pipe.
More severe cases lead to fracture of the pipe or fittings with almost explosive effect and consequent escape of live steam at the fracture. Fracturing of pipes or steam system components can propel fragments that can cause injury or loss of life on it.
