FIELD EXPERIENCE OF THE SEQUENTIAL COMBUSTION SYSTEM FOR THE GT24/GT26 GAS TURBINE FAMILY

Transcription

1 THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS 345 E. 47th St., New York, N.Y GT-22 S The Society shll not be responsible for sttements or opinions dvnced in ppers or discussion t meetings of the Society or of its Divisions or Sections, or printed in its publictions. Discussion is printed only if the pper is published in n ASME Journl. Authoriztion to photocopy for internl or personl use is grnted to librries nd other users registered with the Copyright Clernce Center (CCC) provided $3/rticle or $4/pge is pid to CCC, 222 Rosewood Dr., Dnvers, MA Requests for specil permission or bulk reproduction should be ddressed to the ASME Technicl Publishing Deprtment. Copyright 1998 by ASME All Rights Reserved Printed in U.SA. FIELD EXPERIENCE OF THE SEQUENTIAL COMBUSTION SYSTEM FOR THE GT24/GT26 GAS TURBINE FAMILY Frnz Joos, Philipp Brunner, Mrcel Stlder, Stefn Tschirren ABB Power Genertion Ltd Bden, Switzerlnd ABSTRACT The first units of the Sequentil Combustion System gs turbine fmily re in commercil opertion. The first gs turbine GT24 (6Hz, 165MW-clss) strted the commercil opertion, while the first GT26 (5Hz, 265MW-clss) demonstrtes its performnce t the GT test fcility. More engines re presently in the commissioning phse or will be in the ner future. These turbines re designed to offer incresed output t high GT efficiency. To cheive this, the sequentil combustion system, rehet process with two combustors, hs been developed. Wheres the first combustor is bsed on the proven EV-combustor technology, extensive reserch nd development efforts hve been crried out in developing the len premixed self-igniting second combustor (SEV). This pper is follow-up of the ASME pper 96-GT-315, which described the bsic reserch work concerning the len premixing SEV-burners with self-ignition. The present pper reports the experience gined during commissioning of the first engines. The performnce of the two combustors, s well s the mesured emissions, re discussed nd compred with the expected vlues nd rig test results. Finlly, the potentil of the sequentil combustion system to rech low NOx levels is demonstrted by unveiling the results of the extensive testing progrm during the commissioning phse. INTRODUCTION The GT24/GT26 gs turbine fmily uses proven turbine technology nd pplies it in unique mnner to solve problem tht hs chllenged the power genertion industry since the inception of dvnced technology: the uncoupling of efficiency nd emissions. In stndrd gs turbine designs, higher turbine inlet temperture required for incresed efficiency results in higher emission levels nd incresed mteril nd life cycle costs. To overcome this problem, the sequentil combustion cycle hs been pplied. The results re the GT24 (6 Hz) nd the GT26 (5 Hz) gs turbines. They combine compctness with high specific power, high efficiency, high relibility nd low emissions. The first GT24 hs strted commercil opertion t the Jersey Centrl Power nd Light (JCP&L) Gilbert Sttion (Crds et l., 1996), while the first GT26 ws operted t the gs turbine test center in Bin:-Switzerlnd. The first commercil GT26 hs been ignited t Rheinhfen Power Sttion Krlsruhe, Germny (Scherer et l., 1996). Presented t the Interntionl Gs Turbine & Aeroengine Congress & Exhibition Stockholm, Sweden June 2 June 5, 1998 Downloded From: on 9/17/218 Terms of Use:

2 Fig. 1: GT24/GT26 rrngement following nnulr combustor - the SEV (Sequentil EV) combustor, thereby reheting the ir before expnding it further into four GT24/GT26 PERFORMANCE DATA dditionl low pressure turbine stges. Rted t 265MW, the GT26 delivers bout 5% more output thn conventionl GT13E2 from essentilly the sme footprint. The higher output is the result of increse in the cycle pressure rtio nd the sequentil combustion cycle. Additionlly, the exhust temperture of Fuel input the GT24/GT26 is bout 61 C (113 F) over wide rnge from 5% 5 to 1% engine lod, which is idel for combined cycle (gs nd stem 3 turbine plnt) opertion. The power density of this gs turbine fmily is pproximtely 2% higher compred to other units of this clss. This mens more compct design, shorter blde lengths, lower tip speeds nd therefore lower stresses, leding to higher relibility. SEQUENTIAL COMBUSTION SYSTEM The stright through-flow of the gs turbines, GT24/GT26, looks externlly very similr to conventionl gs turbine, feturing coldend genertor drive, the ir intke system perpendiculr to the shft, xil turbine exhust nd ll csings nd vne crriers horizontlly split. The min prerequisites which llowed such n dvnced nd compct turbine design were developments which hve ll lredy proven their relibility in mny power plnts. The dvnced technology behind the GT24/GT26 is the Sequentil Combustion System (Fig. 1). An efficient 22-stge compressor (Meindl et l., 1995) feeds combustion ir into the first combustor t pressure rtio of 3, i.e. twice the norml pressure. There the fuel is mixed with the high pressure ir nd ignited in the first combustor, the nnulr EV combustion chmber. The hot gses drive first turbine, the single-stge high pressure turbine. Unlike conventionl turbines, fuel is injected in second burner set nd ignites spontneously in the L w Fuel input Power out 2 of 1 ' 4 to generto EntropyS Fig. 2: Thermodynmic cycle of the sequentil combustion system The thermodynmic cycle (Fig. 2) is chrcterized by split of the combustion process into two stges, which re seprted by n expnsion to n intermedite pressure level. In this so clled rehet process, energy is dded to rech higher verge temperture. This results in higher thermodynmic efficiency nd higher power density 2 Downloded From: on 9/17/218 Terms of Use:

3 in comprison to conventionl single combustion gs turbine process with the sme turbine inlet temperture. Thus in the sequentil combustion cycle, for the sme power output, lower turbine inlet temperture cn be used. Sequentil combustion is not new in the power genertion history. ABB hs delivered 24 plnts during the 5's nd 6's with vrious combintions of intercooling in the compressor nd two stgecombustions in the turbine. Nine of these plnts re still in opertion. This history underlines ABB's long experience with sequentil combustion systems (Frutschi, 1994). ENGINE OPERATION CONCEPT The GT24/GT26 engines re optimized for combined-cycle opertion. High therml efficiencies nd low emissions, even during prt-lod opertion, re chieved by the two combustors with individul fuel control nd three rows of djustble inlet guide vnes. These vnes llow the possibility of reducing the combustion ir flow down to 6% of the full lod mss flow. The engine opertion concept is summrized in Fig. 3. The engine is strted nd ccelerted with the EV combustor in opertion. For stbility resons, piloting of the EV burners by diffusion flmes is used. At pproximtely 2% reltive engine lod, the EV burners re switched to premix opertion followed by ignition of the SEV combustor. During further loding, the EV combustor opertes t constnt exit temperture, while the SEV combustor temperture is incresed. At close to 4% reltive engine lod the vrible inlet guide vne (VIGV) is opened, then more fuel is supplied to the two combustors. The exhust temperture of the GT is then kept constnt until full lod is reched. With fully opened VIGV, full lod is reched by lst smll increse of the combustor tempertures. EMISSION BEHAVIOUR OF THE SEQUENTIAL COMBUSTION SYSTEM NOx formtion depends on the temperture, pressure nd residence time in high temperture regions inside the combustion chmber. Becuse ll combustion ir is premixed with the fuel, regions inside the combustor with higher flme temperture thn the combustor exit temperture re voided. In both the EV nd SEV combustors, high temperture residence times re more thn 5% shorter thn in conventionl combustors. This dvntge of the sequentil combustion system cn be utillized becuse the second combustor will burn ll CO nd UHC of the EV combustor in less time becuse of the high inlet temperture. The design of the SEV combustor provides n dditionl dvntge. In the SEV burner, where incoming hot gs hs considerble lower 2 content thn norml ir, less oxygen is vilble for NOx formtion. Furthermore, becuse the SEV ir is t temperture considerbly higher thn conventionl combustion ir, it requires less heting to rech flme temperture. Both of these NOx mitigting phenomen re known from other combustion technologies, which employ exhust gs recircultion. Given tht lrge mount of the fuel is burned in the SEV combustor with ultr low NOx formtion, the NOx emission vlues (mesured s vppm 15% 2) re lower t the SEV exit thn t the SEV inlet. This phenomenon results from the consumption of oxygen within the SEV combustor with miniml NOx production; it will be demonstrted during the discussion of the engine emission below. DESIGN FEATURES OF THE GT24/GT26 EV-COMBUSTOR The first combustor is n nnulr combustion chmber equipped with 3 proven dry low-nox EV-burners. The Environmentl (EV) burner - the result of reserch strted in is recent step in ABB's development progrm (Sttelmyer et l., 199). This engine opertion concept llows high degree of flexibility over the entire opertion rnge. The EV burners operte under optiml design conditions from 25% lod up until full lod with pure premixed flme without piloting. Also, the SEV combustor exit temperture nd the VIGV position cn be djusted to meet the optiml requirements concerning the emissions, the gs turbine or combined cycle efficiency nd turbine requirements. m engine power /%/ Fig. 3 Engine opertion concept of the GT24/GT26 Fig. 4 EV-burner set Downloded From: on 9/17/218 Terms of Use:

4 The EV burner provides the benefit of low NOx combustion without wter or stem injection, nd cn be operted on gs or liquid fuel. The burner is shped like two hlf-cones slightly offset sidewys to form two inlet slots of constnt width running the full length of the component (Fig. 4). The combustion ir enters the cone through these slots while the min gseous fuel is injected through series of fine holes on the supply pipe situted next to the ir inlet slots. The gseous pilot fuel s well s the liquid fuel is injected by nozzles t the cone tip (Fig. 5). With this rrngement fuel nd ir spirl into vortex form nd re mixed intensively. Gs Liquid fuel Gs Pilot LGs l chmber. Beneficilly, the flme hs no contct with the wlls of the burners. DESIGN FEATURES OF THE SEV COMBUSTOR In the nnulr SEV combustor, the combustion process is repeted in similr fshion s in the EV: vortex genertion, fuel injection, premixing nd vortex brek down. The SEV combustor consists of 24 diffusor-burner ssemblies, rrnged round the circumference, followed by single, nnulr combustion chmber surrounded by convection cooled wlls. The exhust gs from the high pressure turbine enters the SEV combustor through the diffusor re. Combustor temperture uniformity in the SEV, like in the EV, is determined by the sptil homogenity of the fuel/ir mixture which is gin ccomplished by the use of vortices. Ech SEV burner contins delt-shped wings to swirl combustion ir into vortices. These wings re formed like rmps nd re locted on ll four of the burners interior wlls. (Fig. 7; Eroglu et l., 1998). Fig. 5 function of the EV burner; mss flow scheme These burners were first pplied commercilly in the silo combustor system of the GT1IN gs turbines in 199. In 1993, the EV-burner ws utilized in the nnulr combustor rrngement of the GT13E2 gs turbine (Aigner et l., 199) nd lter in type GT8, GTI 1N2 nd GTIO s well. Since tht time, over 8, hours of opertion hve been logged on these units. Fig. 7 View from the SEV combustor to the SEV-burner with vortex genertors Fuel is then injected through 24 ir-cooled fuel nozzles, distributing it in mnner which forms perfect fuel/ir mixture prior to combustion. The fuel jet is surrounded by cool crrier ir delys spontneous ignition until the combustion chmber which follows the burner re. Becuse of the elevted tempertures of the high pressure turbine exhust gses, the fuel/ir mixture ignites by itself under the control of the mentioned crrier ir. In the combustion chmber, like in the EV burner, combustion occurs in single, stble flme ring, operting smoothly cross the entire lod rnge. Fig. 6 EV combustor rrngement The nnulr design (Fig. 6) is dvntgeous becuse it provides perfect, even, circumferentil temperture profile, resulting in improved cooling, longer blde life nd lower emisions. Rdil temperture uniformity is ccomplished by premixing virtully ll incoming ir with the fuel in the EV burner nd by the bsence of film cooling in the convection cooled combustor wlls. This produces single, uniform flme ring in the free spce of the EV combustion An extensive reserch nd development progrm hs been crried out in developing the len, self igniting rehet combustor. The development of the burner nd the combustor ws bsed on wind tunnel nd wter chnnel experiments, CFD-clcultions nd combustion tests t tmospheric nd high pressure conditions. Vlidtion tests hve been crried out on engine prts t rel engine conditions (Joos et l., 1996). 4 Downloded From: on 9/17/218 Terms of Use:

5 ENGINE INSTRUMENTATION To confirm the design, the prototype engines hve been equiped with bout 15 mesurement positions ech (Crels et l., 1996). Concerning the combustor issues, the emission nd hot gs tempertures cn be mesured behind the HP-turbine s well s behind the LP-turbine. Three emission probes nd 24 hot gs probes re situted behind the HP-turbine to mesure the circumferentil distribution, while 3 thermocouples behind the LP-turbine llow exhust temperture mesurements to be tken t three rdil nd 1 circumferentil positions. Additionlly, mteril tempertures hve been mesured t ll interesting prts i.e. combustor liners s well s t the burners. Ech combustor is provided with pulstion probe to monitor the pulstion behviour. The mesurement of emission in front nd behind the SEV combustor enbles seprte determintion of the NOx formtion for both the EV nd SEV combustors. For comprison, the NOx emissions re clculted reltive to the mount of fuel dded to ech combustor. Additionlly, the NOx, CO nd smoke emissions re monitored t the stck. TEST PROCEDURE The test procedure hs been crried out with considertion to the previously described opertion concept. At different lods vrition of the combustor firing tempertures nd VIGV settings were conducted to exmine the influence of these prmeters to the engine performnce nd emission behviour. COMBUSTOR COOLING TECHNOLOGY For EV combustor cooling, ll ir delivered from the compressor cn be used s it is fed to the burner fter cooling the liner. This is n exmple of pure convective cooling. Only smll mount of seling lekges flows directly into the combustor. The liner segments re designed s lrge prts to minimize the lekge. Ech of the 3 burner segments consists of two, TBC coted liner segments nd of one, impingement cooled front pnel round the burner. An innovtive cooling mechnism ws developed to fit ll requirements of the self-igniting premixed SEV combustion chmber. The minimiztion of the combustor's cooling ir consumption ws n importnt gol during the development process of the sequentil combustion system becuse the cooling ir of the SEV combustor bypsses the HP turbine. This requirement is contrry to those for convective cooled combustor within stndrd cycle gs turbine, where the pressure drop must be minimized nd therefore the mximum mount of ir must be used for cooling. Furthermore, specil ttention ws pid both to low sensitivity of the cooling effectiveness to vrition in the imposed boundry conditions nd to robust hrdwre construction. Essentilly counterflow cooling system with full het recovery is used where virtully ll cooling ir is mixed with the hot gs delivered from the HPT hed of the flme. After hving cooled the combustor liner wlls vi convective cooling, the cooling ir is gin used in the effusion cooling scheme of the SEV burner. This mens tht the full mount of cooling ir is mixed into the combustion ir upstrem of the flme, thereby lowering the flme temperture nd therefore the NOx formtion. In Fig. 8 the mesured effectiveness (i.e. the dimensionless wll temperture) of the SEV liner cooling is shown s function of the coolnt mss flow function. This function is defined s the rtio of the het cpcity rte of the cooling ir to tht of the hot gs wetted surfce nd therefore s the inverse of the number of het trnsfer units used in het exchnger theory (see Kys nd Crwford, 1993). In high pressure tests under rel engine conditions, ll combustor liner tempertures remined well below 8 C, thus supporting the modelling of the het trnsfer process W.4 on =.2. rig test idel trend engine Coolnt Mss Flow Function [-] Fig. 8: mesured cooling effectiveness of the SEV liner GAS TEMPERATURE PROFILE AT TURBINE EXIT The temperture distribution t the combustor outlet is influenced by the qulity of the fuel distribution system s well s of the burner ir flow. Air lekges lso influence the temperture distribution. Uneven combustor temperture distribution cuses both higher NOx or CO formtion nd higher cooling ir requirements for the turbines. Therefore, for improvement it is necessry to know the temperture distribution t lest t the combustor outlet. The esiest wy to ssess the combustor outlet profile is to mesure behind the turbine. However, the cooling ir ddition from the turbine blding, pltforms nd from the lekges s well s secondry flows in the turbine stges even out the temperture profile. This mkes it difficult to bckclculte to the combustor exit. Conventionlly, the temperture distribution of the combustor is mesured behind the lst stge of the turbines. The vilbility of hot gs thermocouples behind the first turbine stge gives n improved picture of the temperture distribution behind the combustor. Figure 9 shows the circumferentil distribution of the hot gs t high pressure turbine (first stge) outlet reltive to the verge outlet temperture t full lod gs opertion. The devition from the verge is between the rnge of +- 5%. Downloded From: on 9/17/218 Terms of Use:

6 Mesured behind the engine, i.e. t the outlet of the LP turbine, the circumferentil temperture distribution of the mid rdius is in the rnge of +- 5% (Fig. 1). A rdil temperture distribution is lso possible, cused by the ddition of pltform cooling ir of the turbine. Although the devition from the men vlue is lower thn 5%, further improvement will be crried out concerning the fuel distribution system nd the seling. while the UHC emission is lower thn one vppm (15% 2) t opertion conditions bove 6% engine lod. Tuning the SEV ignition nd VIGV will shift the CO/UHC pek to the lod rnge of 2% to 5% engine lod, or in other words, llow opertion t lod conditions higher thn 5% with emissions like those mesured in the opertion rnge of 6% to 8%. This hs been demonstrted t the Birr engine tests s described lter. N 1 1 Q 1 1 m 1 w Reltive engine lod /%I Fig. 11: mesured emission t gs opertion (GT24 first commercil engine) Fig. 9: reltive hot gs temperture distribution behind the HP turbine in the mid of the hot gs chnnel t GT26 full lod gs opertion reltive to the verge At lods lower thn 2% only the EV combustor in premix mode opertes with low NOx nd CO/UHC emissions. During the ignition phse of the SEV, the CO/UHC vlues increse due to the low temperture increse of the SEV combustor. This low increse ws selected to obtin smooth, robust ccelertion without switching of severl burner groups or VIGV. N Aso 1 E c 25 E W NOx CO Bo. Opcity %.svs^. s q $db^9s ^.^YiP e^oen m ^o Ql^o 7 Fig. 1: reltive hot gs temperture distribution behind the LP turbine t three rdil positions in the hot gs chnnel t GT26 full lod gs opertion reltive to the verge Reltive engine lod /"/./ Fig. 12: mesured emission t oil opertion (GT24 first commercil engine) mwter/moil EV = 1.2; mwter/moil SEV = 1. EMISSION Results of GT24 tests t Gilbert The emissions of the first commercil GT24 engine s mesured in the stck t gs dry opertion is shown in Fig. 11. In the rnge of 5% to 1% reltive engine lod, the NOx emissions re below 25 vppm (15%2). The CO vlues, which were reltively high during the SEV ignition, decrese to below 1vppm t 5% lod, decresing further to vlues lower thn 1 vppm (15% 2) t lods higher thn 9%, During oil opertion, the NOx emission re below 42 vppm (15%2) over the entire lod rnge, while the CO vlue stys well below lvppm (15%2) t higher lods thn 5% (Fig. 12). The exhust gses re visible for short time only during SEV ignition t round 3% lod. 6 Downloded From: on 9/17/218 Terms of Use:

7 W C') C) ) x z v I- 1 ^= 1 v W s W Y 1 z gs pi of w gs premix o gs opertion o oil opertion (m wter/ m oil =1.2) Reltive engine lod I%I Fig. 13: mesured EV NOx formtion To evlute the emissions formed in the EV nd SEV combustors, the fuel relted vlues must be compred. Typicl vlues of NOx emissions mesured behind the HP turbine, in front of the SEV combustor, re shown in Fig. 13. The premix flme of the EV burner forms bout 1 g NOx / kg EV fuel during gs opertion nd bout 5 to 7 g NOx / kg EV fuel during oil opertion over the entire opertion rnge. The fct the NOx formtion is nerly independnt from the pressure increse nd VIGV opening during 4% to 9 % lod, shows the high mixing qulity of the EV burners. NOx emissions from the diffusion type pilot flme re round 25 g NOx / kg EV fuel. c ^ m >3 ^ 1 I_ - >Iu N NY z gs opertion p oil opertion (m wter! m oil1.2/1.4) e Reltive engine lod 1%/ Fig. 14 Mesured engine SEV NOx production gs opertion oil opertion I. o Reltive engine lod [/] Fig. 15: Mesured SEV NO x production (rig test) Becuse the NOx emissions hve been mesured in front nd behind the SEV combustor, the emissions formed in the SEV combustor, cn be determined seprtely (Fig. 14). During gs nd oil opertion the NOx formed in the SEV is bout.5 g NOx / kg SEV fuel. It is hlf the vlue of the NOx formed in the EV combustor during gs opertion nd bout 1/8th of the vlue formed during oil opertion. These vlues clerly demonstrte the low NOx formtion feture of rehet combustor with low combustor temperture increses nd with lower 2 content in the burning ir. The engine mesurements vlidtes the rig mesurements crried out during the development of the SEV combustor s shown in Fig. 15. During the rig tests incresing NOx formtion ws observed to be dependnt upon the temperture increse of the SEV combustor, while the engine mesurements show nerly no influence of the engine lod. Results of GT26 tests t Birr Specil ultr low emission runs hve been crried out t the ABB test center in Bin with the first GT26 to demonstrte the future emission potentil of the sequentil combustion concept (Fig. 16) O 1. fl i L^ rel engine lod 1%! Fig. 16: mesured emission t gs opertion of GT26 t ABB test center; ultr low emission run Without difficulties, 15 vppm NOx (15%2) with CO vlues below 5vppm nd UHC vlues below lvppm (15%2) could be chieved. These low emissions could be obtined during the lod rnge of 5% to 1% lod. PULSATION Pressure pulstion, when occuring in combustor of gs turbine, cn vibrte lrge engine prts such s liner segments. If the pulstion mplitudes re high or if the design is too wek, fixtion dmge cn be cused. The design of ll engine prts nd their fixtion hve been crried out in mnner, such tht ll lrge res re connected nd forced dmping cn be chieved. This robust design will withstnd high vibrtion levels. Nevertheless, the pulstion of the combustors is monitored by mesurements of the pressure fluctution inside of the combustor. The excited frequencies led in most cses to stnding wves. Therefore it is of importnce to mesure t regions with mximum mplitudes. These positions hve been determined by mesurement of the pulstion t severl plces long the combustor. 1. Downloded From: on 9/17/218 Terms of Use:

8 The evlution of these mesurements llows pulstion investigtion, with one position tken s the stndrd mesurement. The mesurements re evluted in the rnge of 1 to 1Hz E N SEV Pulstion. EV Pulstion combustion system hs been instlled. The first GT24 nd GT26 engines hve been commissioned. Extensive mesurements t both design nd off design conditions showed relible opertion. The mesured emissions re below the gurntee vlues. While conducting specil low emission tests, the potentil of lower emissions over wide lod rnge hs been demonstrted. ACKNOWLEDGMENT The presented new combustor hs been developed within tem environment. Not ll members of this tem cn be mentioned s couthors of the pper. Therefore we would like to cknowledge the contribution of ll collegues. 1 1e 75 E W 2 so r 25 rn w r moi = mwterimoilsev=1 ice, Reltive Power Lod (%) Fig. 17. mesured pulstion t gs opertion (GT24) The pressure pulstions mesured inside the combustors during GT24 gs opertion re shown in Fig. 17. During loding with EV pilot opertion, the mesured pulstion level ws bout 25mbr RMS. During the 1sec durtion of the EV burner switch over from pilot to premix opertion short time pulstion pek cn be observed due to the chnge of the flme loction within the EV burner. During premix loding, the pulstions of the EV combustor re lwys below 5mbr. At the sme time the pulstions of the SEV combustor re lwys below the pulstion of the EV combustor. o ^ ee l.fir +. =!. ;><. sr r Reltive engine lod 16/.! REFERENCES Aigner, M., Myer, A., Schiessel, P. nd Strittmtter W., 199, "Second Genertion Low Emission Combustors for ABB Gs Turbines: Tests under Full engine Conditions," ASME 9-GT- 38. Crels, Y. J., Ldwig, M., nd Mrchmont, C., 1996, "Commissioning, Testing nd Vlidtion of ABB's GT24 t JCP&L's Gilbert Genertion Sttion," Power Gen Asi 96, New Deli. Eroglu, A., Dobbeling, K., Joos, F. nd Brunner, P., 1998, "Vortex Genertors in Len-Premix Combustion", submitted for IGTI/ASME 1998 Stockholm. Frutschi, H.U., 1994, "Advnced Cycle system with new GT24/GT26 turbines: - historicl bckground," ABB review: 1/ Joos, F., Brunner, P., Schulte-Werning, B., Syed, K. nd Eroglu, A., 1996, "Development of the Sequentil Combustion System for the ABB GT24/GT26 Gs Turbine Fmily," IGTI/ASME, 96-GT-315, Birminghm. Kys, W.M. nd Crwford, M.E., 1993, "Convective Het nd Mss Trnsfer", McGrw-Hill, New York. Meindl, T., Frks F. nd Klussmnn, R., 1995, "The Development of multistge compressor for Hevy duty industril gs turbines," ASME Houston, 95-GT-371. Sttelmyer, T., Felchlin, M., Humnn, J., Hellt, J. nd Steyner, D., 199, "Second Genertion Low Emission Combustors for ABB Gs Turbines: Burner development nd Tests t tmospheric Pressure," ASME 9-GT-162. Scherer, V. nd Schen er, D., 1996, "The Gs Turbine GT26 in Combined Cycle Appliction: Conversion of Col Power Plnt into modem combined Cycle firing nturl gs nd Oil No 2," IGTI/ASME 96-GT-424, Birminghm. Fig. 18. mesured pulstion t oil opertion (GT24) The pulstion levels during oil opertion cn be seen in Fig. 18. The pulstion levels of the EV combustor stys lwys t bout 3 mbr while the SEV pulstions increse during loding from 3 to 6mbr RMS. All mesured pulstion levels re t cceptble levels for longtime opertion. SUMMARY To chieve high cycle efficiency t moderte turbine inlet tempertures, s well s optiml gs turbine exhust tempertures for the stem cycle in combined cycle pplictions, sequentil 8 Downloded From: on 9/17/218 Terms of Use: