ÀÎÅͳÝÈÇаøÇÐ+±¸±Û+³×À̹ö
ÀÚµ¿·Î±×ÀÎ
ÄÁÅÙÃ÷ | contents
ÀϹݰԽÃÆÇ
Q&A°Ô½ÃÆÇ
°øÇÐ S/W
½ºÅ͵ð | study
´ÜÀ§È¯»ê
³óµµ°è»ê
ÀϹÝÈÇÐ
È°øÀϹÝ
È°ø½Ç¹«
> > > > ÆßÇÁÀÇ °³¿ä > > 1. ÆßÇÁ¶õ? > > ¾×ü¿¡ ¿¡³ÊÁö¸¦ ÁÖ¾î Àú¾ÐºÎ¿¡¼ °í¾ÐºÎ·Î À̼ÛÇÏ´Â ±â°è. > > 2. ÆßÇÁÀÇ ±âº» ´É·Â > > a. Suction Head(ÈíÀÔ¼öµÎ : ²ø¾î ¿Ã¸®´Â ´É·Â) > > Åë»ó ÆßÇÁÀÇ Suction Head´Â 6~8M°¡ º¸ÅëÀ̸ç, ÀÌ°ÍÀº ÆßÇÁÀÇ ±¸Á¶»ó > Àý´ë Áø°øÀº ºÒ°¡´ÉÇϱ⠶§¹®ÀÌ´Ù. > ÀÓÆç·¯ÀÇ ¼ö¸¦ Áõ´ë½ÃÅ°´Â °ÍÀº Discharge Head°¡ Áõ°¡ÇÏ´Â °ÍÀÌ°í > Suction Head¿Í´Â ¹«°üÇÑ °ÍÀÌ´Ù. > > b. Discharge Head(ÅäÃâ¼öµÎ : ¹Ð¾î ¿Ã¸®´Â ´É·Â) > > ÆßÇÁÀÇ ±¸Á¶³ª Á¾·ù¿¡ µû¶ó ¿©·¯ °¡Áö ¹æ¹ýÀ¸·Î ¾ó¸¶µçÁö °¡´É. > > 3. ÆßÇÁÀÇ ¿ëµµ > > a. ³·Àº °÷¿¡¼ ³ôÀº °÷À¸·Î À̼ÛÇÒ ¶§. > b. ³·Àº ¾Ð·Â¿¡¼ ³ôÀº ¾Ð·ÂÃøÀ¸·Î À̼ÛÇÒ ¶§. > c. ÁÖ¾îÁø ½Ã°£³»¿¡ À¯Ã¼ÀÇ À¯·®À» Áõ°¡ ½Ãų ¶§. > > 4. »ç¿ëµÇ¾îÁö´Â ¿ë¾î. > > a. Capacity (Q) : ´ÜÀ§ ½Ã°£³»¿¡ È帣´Â À¯Ã¼ÀÇ ¿ëÀû > . > GPM( Gallon per Minute) > H3/Hr( cubic meter per hour) > > b. Head (H) : ÆßÇÁ°¡ ¿Ã¸± ¼ö ÀÖ´Â À¯Ã¼ÀÇ ³ôÀÌ(m), ÆßÇÁ°¡ ³¾ ¼ö ÀÖ´Â ¾Ð·Â(kg/cm2) > > static pressure head > dynamic velocity head > static elevation head > > c. Pressure (P) : ´ÜÀ§ ¸éÀû´ç ÀÛ¿ëÇÏ´Â Èû > > Force/area = PSI ¶Ç´Â kg/cm2 > Gauge Pressure > Absolute Pressure = gauge Pressure + ´ë±â¾Ð(Atmosphere) > > d. Velocity (V) : ÆßÇÁÀÇ ¹è°ü¿¡¼ Áß¿äÇÑ º¯¼öÀ̸ç Åë»ó Æò±ÕÄ¡ »ç¿ë > > V = Q/A, ft/sec or m/s > > e. Friction Loss (Hf) : À¯Ã¼°¡ °ü¼ÓÀ» È带 ¶§ °ü³»¿¡¼ ¹ß»ýÇÏ´Â ¼Õ½Ç. > > ÁÖ¿ä ¿µÇâÀÎÀÚ : °î°ü, °ü°æÀÇ º¯È, °¢Á¾ ¹ëºê·ù > À¯Ã¼ ÀÚüÀÇ ¼Ò¿ëµ¹ÀÌ¿¡ ÀÇÇÑ ¸¶Âû ¼Õ½Ç. > > f. Suction Head > > Static Suction Head = Ps + Hs > > Total Suction Head = Static Suction Head - Hfs > Ps : ÈíÀԾ׸鿡¼ ¾Ð·Â. > Hs : ÈíÀԾ׸éÀÇ ³ôÀÌ. > Hfs : ÈíÀÔ°üÀÇ ¸¶Âû¿¡ ÀÇÇÑ ¼Õ½Ç. > > g. Discharge Head > > Static Discharge Head = Hd + Pd > > Total Discharge Head = Static Discharge Head + Hdf > Pd = ÅäÃâ¾×¸é¿¡¼ ¾Ð·Â. > Hd = ÅäÃâ¾×¸éÀÇ ³ôÀÌ. > Hdf = ÅäÃâ°üÀÇ ¸¶Âû¿¡ ÀÇÇÑ ¼Õ½Ç. > > h. System Head ( TDH) > > Total Differential Head = Discharge Head - Suction Head > > i. Bernoulli's Equation > > Pressure Head(¾Ð·Â¼öµÎ) + Velocity Head(¼Óµµ¼öµÎ) + Elevation Head(À§Ä¡¼öµÎ) = Const(»ó¼ö) > > P/¥ã + ¥ô©÷/2g + Z = const. > > P : À¯Ã¼ÀÇ ¾Ð·Â. > ¥ã : À¯Ã¼ÀÇ ºñÁß·®. > ¥ô : À¯Ã¼ÀÇ Æò±Õ¼Óµµ > 9 : Á߷°¡¼Óµµ > Z : À§Ä¡ÀÇ ³ôÀÌ. > > > j. Net Positive Suction Head ( NPSH) > > À¯Ã¼ÀÇ Æ÷ÈÁõ±â¾ÐÀ» ÃÊ°úÇÏ¸é¼ ÆßÇÁ¿¡ À¯ÀԵǴ À¯Ã¼¿¡³ÊÁöÀÇ ¾ç. > > @ NPSHa(°¡¿ëÇÑ Á¤¹Ì À¯È¿ ÈíÀÔ ¼öµÎ) > À¯Ã¼ÀÇ Total Suction head ¿Í Vapour PressureÀÇ Â÷ÀÌ > NPSHa = Hs + Hatm - Hvp (Àý´ë¾ÐÀ¸·Î Ç¥±â) > > @ NPSHr(¿ä±¸µÇ´Â Á¤¹Ì À¯È¿ ÈíÀÔ ¼öµÎ) > ÆßÇÁ³»¿¡¼ °¡Àå ¾Ð·ÂÀÌ ³·Àº ºÎÀ§ÀÇ À¯Ã¼¿¡³ÊÁöÀÇ °¨¼Ò > > @ NPSHa > NPSHr > NPSHa´Â ¹Ýµå½Ã NPSHrº¸´Ù Ä¿¾ßÇÑ´Ù. > ¿©À¯À²Àº Àû¾îµµ 1.5M ¶Ç´Â 20%ÀÌ»óÀÌ µÇ¾î¾ß ÇÑ´Ù. > > @ NPSH¸¦ ¹Ýµå½Ã °í·ÁÇØ¾ß ÇÒ °æ¿ì. > > 1. ÆßÇÁ¸¦ À¯Ã¼¸éÀ§¿¡ ¼³Ä¡ÇÒ ¶§. > 2. ÈíÀÔÅÊÅ©¿¡ ¾Ð·ÂÀÌ °É·Á ÀÖÀ» ¶§. > 3. Áõ±â¾ÐÀÌ ¸Å¿ì ³ôÀº ÆßÇÁ¸¦ À̼ÛÇÒ ¶§. > 4. ÈíÀÔ ÆÄÀÌÇÁ ¶óÀÎÀÌ ±æ ¶§. > 5. ½Ã½ºÅÛÀÌ Çؼö¸éº¸´Ù »ó´çÈ÷ ³ô°Ô ¼³Ä¡µÉ ¶§. > > k. Cavitation > > 1. ¾Ð·ÂÀÇ °¨¼Ò(impeller eyeºÎ)·Î ÀÎÇØ ¹ß»ýµÈ ±âÆ÷°¡ ¾Ð·ÂÀÇ Áõ°¡(impeller endºÎ)·Î > ÀÎÇØ ÆÄ¿µÇ´Â Çö»ó. Áï, NPSHa <= NPSHr ÀÏ °æ¿ì > > 2. NPSHrÀÇ ÃøÁ¤¹æ¹ý(hydraulic institute standards) > ÁÖ¾îÁø À¯·®°ú ¾çÁ¤, ȸÀü¼ö¿¡¼ ¾çÁ¤À» 3%ÇÏ°µÇ°Ô ÈíÀÔÁ¶°ÇÀ» º¯È¯ ½ÃÄ×À» ¶§ > ÃøÁ¤µÈ NPSHaÀÇ °ªÀ» NPSHrÀ̶ó°í ÇÑ´Ù. > > 3. ÄɺñÅ×À̼ÇÀ¸·Î ¹ß»ýÇÏ´Â Çö»ó. > ¼ÒÀ½(noise) > Áøµ¿(vibration) > ÆßÇÁ ºÎÇ°µéÀÇ ¼Õ»ó. > > l. Power (P) > > @ Pump Input Power (Pi) > > ¿øµ¿±â¿¡ ÀÇÇÏ¿© ÆßÇÁ¸¦ ¿îÀüÇÏ´Â µ¥ ÇÊ¿äÇÑ µ¿·Â. > Break Horse Power (BHP : Ãൿ·Â) > BHP = T x N / 71620 > N = ÃàÀÇ È¸Àü¼ö (RPM) > T = Åä¿ÀÅ©, kg-cm > > °øĪ°î¼±»ó µ¿·Â(Pi) : ¹°À» ±âÁØÀ¸·Î ½ÃÇèÇÑ °ª. > Pi(liquid) = Pi(water) x SG(liquid) > > @ Pump Output Power (Po) > > ÆßÇÁ¿¡ ÀÇÇÏ¿© ¾×ü¿¡ °ø±ÞµÇ´Â µ¿·Â. > Liquid Horse Power (LHP : ¼öµ¿·Â) > LHP = ¥ãQH > ¥ã : ºñÁß·®. > > m. Efficiency (Eff) > > ¿ÜºÎ¿¡¼ °¡ÇØÁØ µ¿·Â¿¡ ´ëÇÑ ½ÇÁ¦ ÀÏÇÑ ¾ç. > Eff(%) = Output Power (Po)/Input Power(Pi) > = { m©ø/hr x Head(m) x Sg} / { 367.2 x Pi(kW) } > µ¿·Â¼Õ½Ç (P (loss)) = Pi - Po > ¼Õ½Ç¿äÀÎ : Hydraulic losses in the pump impeller and casing > Mechanical losses in the pump bearing housing > Mechanical losses in the shaft seal. > > n. Affinity Laws(»ó»ç ¹ýÄ¢) > > 1. ȸÀü¼öÀÇ ºñ¸¦ ¾Ë¸é À¯·®, ¾çÁ¤, µ¿·Â, NPSH¸¦ À¯ÃßÇÒ ¼ö ÀÖ´Ù. > > Q2 = Q1 ( N2 / N1 ) > TDH2 = TDH1 ( N2 / N1 ) ©÷ > P2 = P1 ( N2 / N1) ©ø > NPSHr2 = NPSHr1 ( N2/ N1 ) ©ø > ȸÀü¼öÀÇ 10%º¯À§³»¿¡¼ °è»êµÈ È¿À² ¹× NPSH´Â °ÅÀÇ ÀÏÄ¡ÇÑ´Ù. > > 2. ÀÓÆç·¯ÀÇ ºñ¸¦ ¾Ë¸é À¯·®, ¾çÁ¤, µ¿·ÂÀ» À¯ÃßÇÒ ¼ö ÀÖ´Ù. > > Q2 = Q1 ( D2 / D1) > TDH2 = TDH1 (D2 / D1 ) ©÷ > P2 = P1 ( D2 / D1 ) ©ø > ÀÓÆç·¯ÀÇ ¿Ü°æ ºñÀÇ 5% ¹üÀ§³»¿¡¼ °è»êµÈ È¿À²Àº °ÅÀÇ ÀÏÄ¡ÇÑ´Ù. > ´Ü, NPSHr´Â ÀÓÆç·¯ÀÇ ºñ·Î´Â °è»êÇÒ ¼ö ¾ø´Ù. > > >
±Û´äº¯
¡¤ À̸§
¡¤ Æнº¿öµå
¡¤ À̸ÞÀÏ
¡¤ ȨÆäÀÌÁö
¡¤ Á¦¸ñ
¡¤ ³»¿ë
¡¤ ¸µÅ© #1
¡¤ ¸µÅ© #2
¡¤
66
d
d
a
d
134a
* ¿ÞÂÊÀÇ ±ÛÀÚÁß
»¡°£±ÛÀÚ¸¸
¼ø¼´ë·Î ÀÔ·ÂÇϼ¼¿ä.
Copyright 1999.07.10-Now ChemEng.co.kr & 3D System Engineering. (mail : ykjang@naver.com, call 010-4456-8090)