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  shuf-off pressure , head °ü·Ã Áú¹®
  ±Û¾´ÀÌ : È­°ø¾ÈÀüȯ¡¦   °íÀ¯ID : hiano     ³¯Â¥ : 23-04-24 21:54     Á¶È¸ : 1915    
¾È³çÇϼ¼¿ä ȯ°æ¾ÈÀüºÐ¾ß¿¡¼­ ÀÏÇÏ°í ÀÖÁö¸¸ °ü·Ã ¹ý·ü ´ëÀÀÇÏ´Ùº¸´Ï È­°øÂÊÀ¸·Î
±Ã±ÝÇÑ°Ô À־ Áú¹® ³²°Üµå¸³´Ï´Ù.

1. Differential head¿Í total head°¡ °°Àº ¸»Àΰ¡¿ä? 
¾Æ´Ï¸é Differential head°¡ discharge headÀÎÁö.. ¿ë¾î°¡ Çò°¥¸®³×¿ä

2.¡¤ The pump head at shutoff not exceed 120% of the head at the rated capacity point. 
In addition, it is required that pumps be capable of at least a 5% head increase 
at rated conditions by impeller replacement.
¿©±â¼­ rated capacity point´Â ¹«¾ùÀ» ÀǹÌÇÏ´Â °ÍÀϱî¿ä..
120%¸¦ ¾ð±ÞÇÑ °Í º¸¸é shut-off head¸¦ ¸»ÇÏ´Â °Ç°¡¿ä..

3. Pump Discharge Pressure at shut-off = pump shut-off pressure + suction pressure
¶ó°í ½ºÅ×Æijë´ÔÀÌ ´äº¯ ÇÏ½Å°É º»ÀûÀÌ ÀÖ½À´Ï´Ù..!
±×·³ ÆßÇÁ µð½ºÂ÷Áö ÇÁ·¹¼Å=ÆßÇÁ¼³°è ¾Ð·Â À̶ó°í ºÁµµ ¹«¹æÇÒ±î¿ä??
¶ÇÇÑ Pump Discharge Pressure at shut-off ´Â ÅäÃâ¾Ð·ÂÀ» ¸»ÇÏ´Â °ÍÀ̶ó¸é
pump shut-off pressure´Â ¾î¶² ¾Ð·ÂÀ» ¸»ÇÏ´Â °ÍÀΰ¡¿ä.. ÅäÅ»Çìµå¿¡ ´ëÇÑ °ªÀΰ¡¿ä?

¶ÇÇÑ ÇìµåÀÇ °æ¿ì ³×°ÅƼºê ¼®¼Ç ÇìµåÀÇ °æ¿ì, 
ÅäÅ»Çصå=¼®¼ÇÇìµå+µð½ºÂ÷ÁöÇìµå+ÇÁ¸¯¼ÇÇìµå·Î ¾Ë°í ÀÖ½À´Ï´Ù.

P(Shut-off pressure; Pa) = Ruh*g*h + Psuc.
Ruh : ¹Ðµµ(kg/m-3), g : Áß·Â »ó¼ö(m/s-2), h : shut-off head, Psuc. : ÃÖ´ë ÈíÀÔ ¾Ð·Â

ÀÌ·± ½ÄÀ» ¿Ü±¹ »çÀÌÆ®¿¡¼­ ºÃ´Âµ¥¿ä.. ±×·¸´Ù¸é P(Shut-off pressure; Pa) ÀÌ°ªÀÌ ¼³¸íÇØÁÖ½Å
[[Pump Discharge Pressure at shut-off = pump shut-off pressure + suction pressure]]
À§ ½ÄÀÇ(Pump Discharge Pressure at shut-off)°¡ ¸Â´Â °Ç°¡¿ä?

4.¿Ü±¹ ÀÚ·áµéÀ» º¸¸é ¼Ë¿ÀÇÁÇص忡¼­ÀÇ ÅäÃâ¾Ð·Â¿¡¼­ 
1.2¹è¸¦ ÇÏ¿© ¼Ë¿ÀÇÁ ÇÁ·¹¼Å¸¦ ±¸Ç϶ó´Â ÀڷḦ ºÃ´Âµ¥,
P(Shut-off pressure; Pa) = Ruh*g*h + Psuc.
±×·³ Àú½Ä¿¡ (Ruh*g*h*1.2)¸¦ ³Ö°í ±¸ÇÑ P´Â  ÆßÇÁÀÇ ¼³°è ¾Ð·ÂÀ̶ó°í ºÁµµ µÉ±î¿ä? 

È­Çй°Áú°ü¸®¹ý¿¡´Â ÃÖ°í»ç¿ë¾Ð·Â(»ç¿ë »óÅ¿¡¼­ ¹è°ü¿¡ °É¸®´Â ÃÖ°í ¾Ð·ÂÀ» ¸»ÇÑ´Ù.)À¸·Î 
Á¤ÀÇ µÇ¾î Àִµ¥, À̸¦ ¹ëºê°¡ block µÇ¾úÀ» °æ¿ì¸¦ ÃÖ°í »ç¿ëÀ¸·Î ºÁ¾ßÇÒÁö 
°øÁ¤Áß ÆßÇÁ ¼º´É °î¼±»ó Typical operating point¸¦ ÃÖ°í»ç¿ëÀ¸·Î ºÁ¾ßÇÒ Áö ¸ð¸£°Ú½À´Ï´Ù..

½ºÅ×Æijë Stefano   23-04-25 02:01
A1)  Differential Head  ¶Ç´Â Differential Pressure ´Â ÆßÇÁ ÀüÈÄÀÇ Head Â÷ ¶Ç´Â ÀüÈÄ ¾Ð·ÂÂ÷¸¦ ¸»ÇÏ°í
Discharge Head  ¶Ç´Â Discharge Pressure´Â  Suction Head³ª Pressure¿¡ ÆßÇÁÀÇ Differential Head ³ª Pressure¸¦ ´õÇÑ °ªÀ» ¸»ÇÕ´Ï´Ù.  µû¶ó¼­ Differential Head´Â Discharge Head¿Í °°Áö ¾Ê½À´Ï´Ù.

A2) "Rated"ÀÇ Àǹ̴ "¿©À¯¸¦ °¡Áö°í ¼±Á¤µÈ"ÀÇ ¶æÀÔ´Ï´Ù. 
<The pump head at shutoff not exceed 120% of the head at the rated capacity point. >´Â "Pump Shut-off »óÅ¿¡¼­ÀÇ  Head°¡ ¼±Á¤µÈ ¿ë·®Á¡¿¡¼­ ³ªÅ¸³»´Â HeadÀÇ 120%¸¦ ³ÑÁö ¾Êµµ·Ï ÇÒ °Í" À̶ó´Â ÀǹÌÀÌ°í
<.., it is required that pumps be capable of at least a 5% head increase at rated conditions by impeller replacement.>´Â  ¼±Á¤Á¶°Ç°ú µ¿ÀÏ Á¶°Ç¿¡¼­ Impeller¸¦ (´õ Å« Á÷°æÀÇ °ÍÀ¸·Î) ¹Ù²åÀ» ¶§ Àû¾îµµ 5% Head Áõ°¡°¡ °¡´ÉÇÑ ÆßÇÁÁ¾ÀÌ µÇµµ·Ï Ç϶ó"´Â ÀÇ¹Ì ÀÔ´Ï´Ù.    À̴  ±¸¸Å ¼³Ä¡ÇÑ ÆßÇÁÀÇ Head°¡ ºÎÁ·ÇÒ °æ¿ì¿¡ ´ëºñ(Impeller ±³Ã¼ÇÏ¿© ÇØ°á)Çϱâ À§ÇÔÀÔ´Ï´Ù.

A3-1) pump shut-off pressure
ÀÌ´Â Pump ¹èÃâ·®ÀÌ 0ÀÏ ¶§ ¹èÃⱸÃø¿¡ ³ªÅ¸³ª´Â ¾Ð·Â¿¡ ÇØ´çÇϴµ¥  À¯·® 0ÀÏ ¶§ÀÇ ¾Ð·Â¿¡´Ù  Pump SuctionÀÇ ¾Ð·ÂÀÌ ´õÇØÁ® ³ªÅ¸³ª´Â  ¹èÃⱸ Ãø¿¡¼­ ÃÖ°íÀÇ ¾Ð·ÂÀ» ³ªÅ¸³¾ ¶§ÀÇ ¾Ð·ÂÀÔ´Ï´Ù.  Pump Discharge Line¿¡ °É¸±¼ö ÀÖ´Â ÃÖ°íÀÇ ¾Ð·ÂÀ» È®ÀÎÇϱâ À§ÇÑ ¾Ð·Â¿¡ ÇØ´çÇÕ´Ï´Ù. 

A4-1) Total Discharge Head ´Â 
¿îÀüÁß Pump ¹èÃⱸÃø¿¡ °É¸®´Â Àüü Head¸¦ ¸»Çϴµ¥  ÀÌ °ªÀº  ÆßÇÁ°¡ ÇöÀå¿¡¼­ °¡µ¿µÇ°í ÀÖÀ» ¶§ (1) ÀåÄ¡¿¡ °É¸° ¾Ð·Â±îÁö ³ôÀÌ°í(Pressure Head), ¾×À» ³ô°Ô Æۿø®°í(Static Head),  ÆßÇÎÀ¯Ã¼°¡ Èê·¯°¥ ¶§ ¼Õ½ÇµÇ´Â ¸¶Âû¼Õ½Ç (Discharge Line »Ó ¸¸ ¾Æ´Ï¶ó Suction Line, Control Valve µî ¸ðµç Friction Head)¸¦ À̰ܳ»´Âµ¥ »ç¿ëµÊÀ» ÀǹÌÇÕ´Ï´Ù. 

Suction LineÀÌ Pump ¹Ø¿¡ ¼³Ä¡µÇ¾î ÀÖ´Ù¸é  ÀÌ¿¡ ÇØ´çÇÏ´Â Static Headµµ ´õÇØÁÖ¾î ÆßÇÁ°¡ ¼±Á¤µÇ¾î¾ß ÇÕ´Ï´Ù.

Pump À¯·®ÀÌ 0ÀÏ ¶§ÀÇ Discharge Head¿¡ Pump Suction¿¡ °É·ÁÀÖ´Â Static Head¸¦ ´õÇÑ °ªÀÌ µË´Ï´Ù.  Pump À¯·®ÀÌ 0ÀÏ ¶§¿¡´Â  Friction Head°¡ 0ÀÌ µÇ¹Ç·Î  (1) Suction ÃøÀÇ Static Head¿¡ ÇØ´çÇÏ´Â ¾Ð·Â¿¡´Ù  (2) Pump À¯·® 0À϶§ÀÇ Discharge Head¿¡ ÇØ´çÇÏ´Â Â÷¾ÐÀ» ´õÇÑ °ªÀÌ  Pump Discharge Line Shut-off Case¿¡ ¿¬°áµÇ¾î Àִ  Liquid Feed Line & Equipment¿¡ °É¸®´Â ÃÖ°íÀÇ ¾Ð·ÂÀÌ µÇÁö¿ä.

»ó¼¼ÇÏ°Ô ¼³¸íµÇÁö ¾Ê¾ÒÀ» ¶§ÀÇ "Typical operating point"´Â Á¤»ó¿îÀü½ÃÀÇ ¿îÀüÁ¡À» ¸»ÇÕ´Ï´Ù.  ÃÖ°í»ç¿ë¾Ð·Â°ú´Â °ü·Ã¾ø½À´Ï´Ù.
È­°ø¾ÈÀüȯ¡¦ hiano   23-04-25 14:12
´ÊÀº½Ã°£¿¡µµ ´äº¯ÇØÁּż­ °¨»çÇÕ´Ï´Ù ½ºÅ×Æijë´Ô!
´äº¯ÀÌ »ý°¢À» Á¤¸®ÇÏ´Â µ¥¿¡ ¸¹Àº µµ¿òÀÌ µÆ½À´Ï´Ù
Ãß°¡ÀûÀ¸·Î ¸î°¡Áö¸¸ ´õ Áú¹® µå·Áµµ µÉ±î¿ä?

a4-1) ´äº¯ °ü·ÃÇÏ¿©,

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P(discharge pressure) = Ruh*g*h + Psuc. ``````````(°¡)
Ruh : ¹Ðµµ(kg/m-3), g : Áß·Â »ó¼ö(m/s-2), h : shut-off head, Psuc. : suction pressure
-------------------------------------------------------------------------------------------------------------------
Á¦°¡ ÀÌÇØÇÑ´ë·Î Çѹø ¸»¾¸µå·Áº¸°Ú½À´Ï´Ù..

[1]
½Ä(°¡)¿¡¼­ (Ruh*g*h)¿¡ ÇØ´çÇÏ´Â ºÎºÐÀÌ shut-off¿¡¼­ÀÇ differential pressure ÀÔ´Ï´Ù.
À̶§ h´Â shut-off headÀε¥ ÀÌ´Â ÆßÇÁ ¼º´É °î¼±»ó À¯·®ÀÌ 0À϶§¿¡ total head¿¡ ÇØ´ç ÇÏ´Â °ªÀÔ´Ï´Ù.

[2]
¶ÇÇÑ shut-off head¸¦ ¸ð¸£´Â »óȲ¿¡¼­ÀÇ discharge pressure´Â (Ruh*g*h)ÀÇ h¿¡ total head*1.1(API610; shut-off´Â Á¤»ó¾çÁ¤ÀÇ 10%¹üÀ§·Î ¼öµÎ »ó½Â)°ªÀ» ´ëÀÔÇÏ¿© ÃßÁ¤pressure¸¦ ±¸ÇÕ´Ï´Ù.

[3]
ÃÖ°í»ç¿ë ¾Ð·ÂÀº ÆßÇÁÀÇ À¯·®ÀÌ 0ÀÌ°í ¸¶Âû¼Õ½ÇÀÌ 0ÀÎ »óÅÂÀÏ °æ¿ìÀÇ ¾Ð·ÂÀ̹ǷÎ
Pump Discharge pressure(at shut-off)·Î ±¸ÇÑ´Ù.

[4]
¸¶Áö¸·À¸·Î ¼³°è ¾Ð·Â(ÆßÇÁÀÇ ¼³°è ¾Ð·Â, ÆßÇÁ ÈĴܽýºÅÛÀÇ ¼³°è ¾Ð·Â)Àº Pump discharge Pressure(at shut-off) º¸´Ù Å«°ªÀ¸·Î ¼³Á¤ÇÑ´Ù.(KOSHA guide, API610±Ù°Å)

À§ÀÇ ³»¿ëµéÀÌ ¸ÂÀ»±î¿ä?
Stefano    23-04-26 00:47
AA1)  Ruh °¡ ¾î¶² °úÁ¤À¸·Î °è»êµÇ¾ú´ÂÁö ¾Ë ¼ö ¾øÁö¸¸ Pump¿¡ ÀÇÇØ »ó½ÂµÇ´Â ¾Ð·Â¿¡ ÇØ´çÇÏ´Â °ÍÀ¸·Î º¸À̳ª ÀÌ °ªÀÌ À¯·® 0À϶§ÀÇ °ªÀεð ±×·¸Áö ¾ÊÀºÁö È®ÀÎÇØ º¸¼¼¿ä.  Ruh°¡ ¹«¾ùÀÇ ¾à¾îÀÎÁö  ¾î¾ Subscript(÷ÀÚ)¸¦ »ç¿ëÇÏ°í ÀÖ´ÂÁöµµ ¾Ë¾Æº¸¼¼¿ä.

AA2)  Pump  ¼º´É°î¼±ÀڷḦ ÀÔ¼öÇÏÁö ¸øÇÑ °æ¿ì  ÃßÁ¤ÇÏ´Â ¹æ¹ýÀ¸·Î Á¦½ÃÇÑ ¸ð¾çÀ̳ª  API¿¡¼­´Â Normal Diffential Head°ªÀÇ 110%¸¦ ÃëÇÏ¿© Pump ¼º´É°î¼±»ó À¯·® 0À϶§ÀÇ Head¸¸À» ÃëÇÏ´Â °ÍÀ¸·Î º¾´Ï´Ù.

AA3) ÀÌ´Â Pump ÀÚü ¼º´É°î¼±»óÀÇ À¯·®Discharge PressureÀÌÁö ¼³Ä¡µÈ System¿¡ °É¸®´Â Pump Shut-off Pressure¸¦ ÀǹÌÇÏ´Â °ÍÀº ¾Æ´Ò °ÍÀÔ´Ï´Ù \

AA4) KOSHA ȤÀº API Guide´Â  (Pump ¼º´ÉÀ» ¾ð±ÞÇÏ´Â °ÍÀÌ ¾Æ´Ï°í)  ÆßÇÁ°¡ ÇöÀå¿¡ ¼³Ä¡µÇ¾î ÀÖ´Â °æ¿ì, "Pump ¹èÃⱸ¿¡ ¿¬°áµÇ¾î ÀÖ´Â ¹è°ü ¹× ±â±âµéÀÇ ÃÖÁ¾ Ãⱸ°¡ ¸·ÇûÀ» °æ¿ì  "Closed Outlet »óȲ"¿¡¼­ ±× ¹è°ü°ú ±â±â¿¡ °É¸± ¼ö ÀÖ´Â ÃÖ°íÀÇ ¾Ð·ÂÀ» »êÃâÇÏ¿© ¹è°ü ¹× ±â±âÀÇ ¼³°è¾Ð·ÂÀ¸·Î Ç϶ó"´Â ÁÖ¹®ÀÔ´Ï´Ù.

µû¶ó¼­ ¸¸¾à.. (1) Pump Suction Drum¿¡ ¾Ð·ÂÀÌ °É·ÁÀÖ°í  (2) ±× DrumÀÌ Pumpº¸´Ù ²Ï ³ôÀº °÷¿¡ ¼³Ä¡µÇ¾î ÀÖÀ¸¸ç, (3) Pump°¡ °¡µ¿Áß¿¡ À־ ¾Ð·ÂÀ» ³ô¿©ÁÖ°í Àִµ¥ (4) ¾î¶² ÀÌÀ¯¿¡¼­ÀÎÁö  Pump ¹è°ü - ±â±â ¸¦ °ÅÃÄ ±â±â Ãⱸ¿¡ ÀÖ´Â Control Valve°¡ °©Àڱ⠴ÝÇô¹ö·È´Ù´ø°¡  (5) ´©°¡  ±â±â Ãⱸ Block Valve¸¦ Àá±Å¹ö·È´Ù°í ÇÑ´Ù¸é

(1)~(3)¿¡ ÇØ´çÇÏ´Â ¾Ð·ÂÀ» ¸ðµÎ °í·ÁÇÑ Pump Shut-off Pressure¸¦ °í·ÁÇÏ¿© ¿¬°áµÈ ±â±â(Equipment)°¡ ÀÖÀ¸¸é ÀÌ ±â±â¿Í ¹è°üµéÀº ¸ðµÎ ±× ¾Ð·ÂÀ» °í·ÁÇÑ ÃÖ°íÀÇ ¾Ð·ÂÀ» ¼³°è¾Ð·ÂÀ¸·Î ÇØ´Þ¶ó´Â °ÍÀ» ¾Ï½ÃÇÏ°í ÀÖ½À´Ï´Ù.
È­°ø¾ÈÀüȯ¡¦ hiano   23-04-26 14:49
°¨»çÇÕ´Ï´Ù ½ºÅ×Æijë´Ô... Ãß°¡ÀûÀ¸·Î ´õ Áú¹®Çصµ µÉ±î¿ä... °è¼ÓÇؼ­ Áú¹®µå·Á¼­ Á˼ÛÇÕ´Ï´Ù ¤Ì¤Ð¤Ð¤Ð

B1) 

Differential Head  ¶Ç´Â Differential Pressure ´Â ÆßÇÁ ÀüÈÄÀÇ Head Â÷ ¶Ç´Â ÀüÈÄ ¾Ð·ÂÂ÷¸¦ ¸»ÇÑ´Ù°í Çϼ̽À´Ï´Ù.

Àü¾çÁ¤(Total head)´Â ÅäÃâ¾çÁ¤, ÈíÀÔ¾çÁ¤, ¼Õ½Ç¾çÁ¤ÀÇ ÇÕÀÌ°í, ½Ç¾çÁ¤(Actual head)´Â ÅäÃâ¾çÁ¤, ÈíÀÔ¾çÁ¤ÀÇ ÇÕÀ¸·Î ¾Ë°íÀÖ½À´Ï´Ù.

±×·¸´Ù¸é Differential Head  ¶Ç´Â Differential Pressures´Â Àü¾çÁ¤¿¡ ´ëÇÑ °ªÀΰ¡¿ä ½Ç¾çÁ¤¿¡ ´ëÇÑ °ªÀΰ¡¿ä?

B2)

Ht= total head
Hf=friction head
Hd=discharge static head
Hs=suction static head
¶ó Çϸé,
- ÈíÀÔÃøÀÇ ¼öÀ§°¡ ÆßÇÁº¸´Ù ³ôÀº °æ¿ìÀÇ Á¤»ó¾çÁ¤(Rated differential Head)
HT  =  Hf + HD - HS

-ÈíÀÔ ÃøÀÇ ¼öÀ§°¡ ÆßÇÁº¸´Ù ³·Àº °æ¿ìÀÇ Á¤»ó¾çÁ¤(Rated differential Head)
HT  =  Hf + HD + HS

ÀÌ°æ¿ì°¡ ¸Â³ª¿ä?

3)
À§¿¡¼­ ´äº¯ÇØÁֽŠAA4)¿¡ ÀÇÇϸé
(1)~(3)¿¡ ÇØ´çÇÏ´Â ¾Ð·ÂÀ» ¸ðµÎ °í·ÁÇÑ Pump Shut-off Pressure¸¦ ¼³°è¾Ð·ÂÀ¸·Î Ç϶ó´Â °ÍÀÌ °¡À̵åÁöħ ³»¿ëÀ̶ó°í Çϼ̽À´Ï´Ù.

±×·¯¸é Ãß°¡ÀûÀ¸·Î ±»ÀÌ (1)~(3)¿¡ ÇØ´çÇÏ´Â ¾Ð·ÂÀ» ¸ðµÎ °í·ÁÇÑ Pump Shut-off Pressure º¸´Ù ´õ ³ô°Ô ¼³°è¾Ð·ÂÀ» Àâ¾Æ¾ßÇÒ ÇÊ¿ä´Â ¾ø´Â °ÍÀÎÁö¿ä?
½ºÅ×Æijë Stefano   23-05-01 22:46
(0)  Ruh¡Õ?? ¿¡ ´ëÇÑ ´äÀ̾ø½À´Ï´Ù .

<...Àü¾çÁ¤(Total head)´Â ÅäÃâ¾çÁ¤, ÈíÀÔ¾çÁ¤, ¼Õ½Ç¾çÁ¤ÀÇ ÇÕÀÌ°í, ½Ç¾çÁ¤(Actual head)´Â ÅäÃâ¾çÁ¤, ÈíÀÔ¾çÁ¤ÀÇ ÇÕÀ¸·Î ¾Ë°íÀÖ½À´Ï´Ù. ...>  <==À̸»Àº ¾îµð¿¡¼­ À¯·¡Çß´ÂÁö ¸ð¸£°ÚÁö¸¸  Ʋ·È½À´Ï´Ù.   

(1)  Differential Pressure of Pump = Discharge Pressure - Suction Pressure 
      Differential Head of Pump = Discharge Head - Suction Head

(2)  ±âÈ£ ¹× ÷ÀÚ°¡ È¥µ¿½º·¯¿ì¸é ÀÌÇصµ È¥µ¿½º·¯¿ï °ÍÀ¸·Î º¾´Ï´Ù. 
Static Head¸¦ ¼öÀ§ Z·Î ³ªÅ¸³»°í  Pressure Head¸¦ h·Î  Velocity Head¸¦ hv·Î ³ªÅ¸³»°í Friction Head¸¦ hf,  PumpÀÇ Total Head ¸¦ Hp·Î ³ªÅ¸³»¾î ÆßÇÁ ÀüÈĸ¦ ¼ýÀÚ Áï <1=suction,  2=discharge>·Î ±¸ºÐÇؼ­ Bernoulli EquationÀ» Àû¾îº¸¸é È¥µ¿½º·¯¿ü´ø Á¡ÀÌ ¸íÄèÇØÁú °ÍÀ¸·Î º¸ÀÔ´Ï´Ù. 
 
      Z1 + h1 + hv1 + Hp = Z2 + h2 + hv2 + hf  ..........................................(1)  <---velocity head, friction head Æ÷ÇÔ½Ä

      Hp = Total Head of the Pump = (Z2-Z1) + (h2-h1) + (hv2-hv1) + hf ......(2)  <--- ÆßÇÁ¼Ò¿ä head  hf´Â À¯·®ÀÌ ÀÖÀ» °æ¿ì
         
¿©±â¼­  Pressure Head´Â h = p/(¥ñ g)·Î °è»êµÇ°í, Velocity Head´Â hv = v^2/(2g)·Î °è»êµÇ¸ç Friction Head´Â À¯·®ÀÌ ÀÖÀ» °æ¿ì¿¡¸¸ ÇØ´çµÇ±â ¶§¹®¿¡ (2) ½ÄÀº Á¤»ó À¯·®ÀÏ ¶§ÀÇ ¸¶Âû¼Õ½ÇÀÌ °í·ÁµÈ ÆßÇÁÀÇ Total Head °è»ê¿¡ »ç¿ëµÉ ¼ö ÀÖ½À´Ï´Ù.

À§ÀÇ ¼ö½Ä(2)´Â Á¤»ó¿îÀü½Ã ÆßÇÁ°¡ °ø±ÞÇؾßÇÒ ½ÇÁ¦ ¾çÁ¤(Actual Head)¿¡ ÇØ´çÇÕ´Ï´Ù.  Áï ¿©À¯°ªÀÌ ¾øÀÌ µü µé¾î¸Â´Â ÆßÇÁ ÃÑ ¾çÁ¤¿¡ ÇØ´çÇÕ´Ï´Ù.  ÆßÇÁ¸¦ ¼±Á¤ÇÒ °æ¿ì¿¡´Â ¿©±â¿¡´Ù ¿©À¯°ªÀÌ ´õÇØÁ®¾ß ÇÕ´Ï´Ù.  FrictionÀÌ ´Ã¾î³ª°Å³ª  Pump Suction ¼öÀ§°¡ ÃÖÀúÀÏ ¶§ Áï Z1ÀÌ ÃÖ¼Ò°ªÀÏ ¶§¿¡µµ  ÇÊ¿äÀ¯·®À» °ø±ÞÇÒ ¼ö ÀÖµµ·Ï µ¥ÀÌÅͽÃÆ® ÀÛ¼º½Ã ÁÖÀÇÇØ¾ß ÇÏ°í ƯÈ÷ Pump ¼³Ä¡À§Ä¡¿Í ÁÖÀ§ ¹è°ü¼³°è°¡ ¿Ï·áµÇ´Â ´Ü°è¿¡¼­ Pump Suction Line¿¡¼­ÀÇ NPSHÁ¡°Ë ¹× ¹èÃâ°ü Àüü¿¡ ´ëÇÑ Hydraulic Analysis °á°ú¿Í °ø±ÞµÇ´Â Pump Vendor Data¸¦ °ËÅäÇØ ºÁ¼­ ¹ßÁÖ±Ô°ÝÀ̳ª ¹è°ü¼³°èµîÀÇ º¯°æ¿©ºÎ¸¦ ¹Ýµå½Ã È®ÀÎÇؾߠ ½Ã¿îÀü ´Ü°è¿¡¼­ÀÇ "³¶ÆÐ"¸¦ ¸éÇÒ ¼ö ÀÖ½À´Ï´Ù.

±âÁØ ¼öÀ§¸¦ Pump Suction Nozzle Áß¾ÓÀ¸·Î º¼ ¶§  ÆßÇÁº¸´Ù  ³·Àº°÷¿¡ ÀÖÀ¸¸é  Z>0    ÆßÇÁº¸´Ù  ³·Àº °÷¿¡ ÀÖÀ¸¸é Z<0ÀÌ µÇ¹Ç·Î (2) ½Ä¿¡¼­ Z1ÀÌ  À½¼ö°ªÀ̶ó¸é ( Z1 = - Y ,  Y>0, Y= (Àý´ë°ª, ¾ç¼ö°ªÀ¸·Î Ÿ³ª³½) Suction Lift)À̶ó¸é  ùÇ×Àº  (Z2-Z1) = Z2-(-Y) =  Z2 + Y °¡ µË´Ï´Ù.    (Áú¹®¿¡¼­  Hs °ªÀ» »©´Â°ÇÁö ´õÇØÁÖ´Â °ÇÁö È¥µ¿½º·¯¿ö ÇÏ´Â °ÍÀ¸·Î º¸À̴µ¥ ¸ðµÎ ¾çÁ¤Y°ªÀ¸·Î ³ªÅ¸³»º¸¸é¼­ ºÎÈ£°¡ ¾î¶»°Ô ¹Ù²î´ÂÁö È®ÀÎÇØ º¸¼¼¿ä.  (2)½Ä¿¡¼­ ¾çÁ¤ÀÌ +°ªÀ̶ó¸é »©ÁÖ°í ¾çÁ¤ÀÌ -°ªÀ̶ó¸é ´õÇØÁÖ°í..)

(3) ¿©·¯ »óȲ¿¡¼­ÀÇ Pump Shut-off Pressure¸¦ °í·ÁÇÑ Design Pressure
ÀÌ Ç׸ñ ÀÌÀüÀÇ »óȲÀº Pump  ¼±Á¤°ú ¼Ò¿äµ¿·ÂÀ» °áÁ¤ÇÒ ¶§ °í·ÁÇÒ ¶§¿¡ ÀϾ´Â °ÍÀÌ°í ÀÌ(3)Ç׿¡¼­´Â Pump¿¡ ¿¬°áµÇ¾îÀÖ´Â ¹è°üÀ̳ª ±â±âÀåÄ¡°¡ ¿îÀüÁß µµ´ÞÇÒ ¼ö ÀÖ´Â ÃÖ°íÀÇ ¾Ð·ÂÀ» ÆÇ´ÜÇÒ ¶§ °ËÅäÇØ¾ß ÇÒ »óȲ¿¡¼­ ¹ú¾îÁö´Â ÀÏÀÔ´Ï´Ù.

µû¶ó¼­ °ËÅäÇÏ·Á´Â ¹®Á¦°¡  <ÆßÇÁ¸¦ ¼±Á¤Çϱâ À§ÇѰųÄ?>  ȤÀº < ±â±âÀåÄ¡ ¼³°èÁ¶°ÇÀ» À§ÇѰųÄ> ¸¦ ±¸ºÐÇÏ¿©  ÆÇ´ÜÇÏ¿© Âü¿©ÇÏ´Â ¿£Áö´Ï¾îµé¿¡°Ô È¥µ·À» À¯¹ß½ÃÅ°Áö ¸»¾Æ¾ß ÇÕ´Ï´Ù.  ¸Ç óÀ½ Áú¹®ºÎÅÍ ÀÌ µÑÀ» È¥ÇÕÇÏ¿© Áú¹®ÇØ ¿À°í ÀÖ¾ú½À´Ï´Ù.

Pump Suction ¾Ð·ÂÀÌ ¾ø°í ¹èÃâ À¯·®ÀÌ 0ÀÏ ¶§ÀÇ  Pump Shut-off Pressure = Pump Performance Chart»ó À¯·® 0ÀÏ ¶§ÀÇ Head¿¡ »ó´çÇÏ´Â ¹èÃâ¾Ð·Â = P(at no flow) = ¥ñ g h (at Q=0)      <----(2)½Ä¿¡¼­  Z, hv, hf, h1 °ªµéÀÌ ¸ðµÎ 0À϶§ÀÇ h2°ª¿¡ ÇØ´çÇÕ´Ï´Ù.

Pump°¡ Á¤»ó¿îÀüÁß ¼³Ä¡µÇ¾î Á¤»ó¿îÀüÁßÀÏ ¶§ÀÇ Pump Shut-off Pressure´Â (2)½Ä¿¡¼­ hf°ª¸¸ 0À¸·ÎÇÏ¿© °è»êÇÏ¿© °è»êµÇ´Â h2°ª¿¡ ÇØ´çÇÏ´Â PressureÀε¥  ±â±âÀåÄ¡°¡ ¿¬°áµÇ¾î ÀÖ´Â À§Ä¡¿¡ µû¶ó ¾Ð·ÂÀÌ ´Þ¶óÁö¹Ç·Î À̸¦ °í·ÁÇØ¾ß ÇØ´ç ±â±âÀÇ ¼³°è¾Ð·ÂÀÇ ÀûÁ¤¼º ¿©ºÎ¸¦ ÆÇ´ÜÇÒ ¼ö ÀÖ½À´Ï´Ù.   

¿©±â¼­ °è»êµÇ´Â ¾Ð·Âº¸´Ù ±»ÀÌ ³ôÀÌ ÀâÀ» ÇÊ¿ä´Â ¾øÁö¸¸ ¾î¶² ¶Ç´Ù¸¥ »óȲ (¿¹¸¦ µé¾î ¿­ÆØâ, ¹ÝÀÀ, µî)ÀÌ ¹ß»ýÇϰųª  ¹ëºêÀÇ °©ÀÛ½º·± ´ÝÈû¿¡ ÀÇÇÑ ¼ö°ÝÇö»ó (Hammering)µîÀÇ ¿ì·Á°¡ ÀÖ´ÂÁöµµ °ËÅäÇØ º¸¾Æ¾ß ÇÕ´Ï´Ù.
   

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