Research Article Analysis of Humid Air Turbine Cycle with Low- or Medium-Temperature Solar Energy

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1 Photoenergy Volume 2009, Article ID , 9 pges doi: /2009/ Reserch Article Anlysis of Humid Air Turine Cycle with Low- or Medium-Temperture Solr Energy Hongin Zho, Pengxiu Yue, nd Ling Co School of Mechtronics Engineering, Chin University of Petroleum, Beijing , Chin Correspondence should e ddressed to Hongin Zho, honginzhoyin@sin.com Received 1 April 2009; Revised 5 July 2009; Accepted 28 July 2009 Recommended y Gopl Nth Tiwri A new humid ir turine cycle tht uses low- or medium-temperture solr energy s ssistnt het source ws proposed for incresing the mss flow rte of humid ir. Bsed on the comintion of the first nd second lws of thermodynmics, this pper descried nd compred the performnces of the conventionl nd the solr HAT cycles. The effects of some prmeters such s pressure rtio, turine inlet temperture (TIT), nd sollr collector efficiency on humidity, specific work, cycle s exergy efficiency, nd solr energy to electricity efficiency were discussed in detil. Compred with the conventionl HAT cycle, ecuse of the incresed humid ir mss flow rte in the new system, the humidity nd the specific work of the new system were incresed. Menwhile, the solr energy to electricity efficiency ws gretly improved. Additionlly, the exergy losses of components in the system under the given conditions were lso studied nd nlyzed. Copyright 2009 Hongin Zho et l. This is n open ccess rticle distriuted under the Cretive Commons Attriution License, which permits unrestricted use, distriution, nd reproduction in ny medium, provided the originl work is properly cited. 1. Introduction In recent yers, the solr energy s kind of clen nd renewle energy is pplied in mny res. More nd more countries py ttentions to reserching nd developing solr energy nd grdully extend the tremendous scle power genertion. Solr therml power plnts cn produce hightemperture het tht is converted into electricity y conventionl power cycles [1, 2]. The wy of solr energy utiliztion y heting wter into stem through solr collector for gs turine hs developed successfully in test nd technology. Since 1970s, the solr therml power genertion technologies were emphsized in the mjor developed countries, such s the United Sttes, Spin, Germny, nd others. According to incomplete sttistics, inrecent20yers,there re out 20 sets of solr power plnts in the world, nd the solr therml power output is ove 500 MW, nd the iggest solr power is 80 MW [3, 4]. The HAT cycle is n dvnced power genertion system with reltively high efficiencies, low specific investment costs, high power, nd low emissions. In the 1980s, the interest in gs turine cycles with humidifiction towers ws incresed. The humid ir turine (HAT) ws proposed y Y. Mori in 1983, nd susequently, the Jpnese reserchers pplied ptent in 1985 nd RAO pplied in 1989 [5, 6]. In the eginning of the 1990s, reserch progrm on EvGT (evportive gs turine) ws initited in Sweden, nd n dvnced progrm of humid ir turine ws studied in Jpn [7, 8]. Besides, HAT cycles comined with fuel cells hve lso een investigted. Ro nd Smuelsen presented n HAT cycle integrted with solid oxide fuel cell (SOFC) with high therml efficiency of 69.1%. Up to now, mny reserchers hve proposed the concepts of grded use of energy for improving the performnce of HAT cycle [9 14]. In this pper, new mode of HAT cycle tht integrted with solr energy is proposed. In the new system, the solr collector will concentrte the solr energy for heting some circulting wter in order to otin high efficiency of solr energy utiliztion. Menwhile, the min chrcteristics of the novel system will e disclosed. Additionlly, we use the exergy nlysis method to discuss nd investigte some fctors influencing on the performnce of HAT cycle. 2. Description of the New System In the proposed cycle system, solr energy is tken s n dded het resource for concentrting energy for the cycle.

2 2 Photoenergy As shown in Figure 1, solr collector (13) is rrnged to sor low- or medium-temperture solr energy for the dditionl circulting wter in order to increse the wter mount nd temperture for the sturtor (7). The mient ir enters the low-pressure compressor (1) nd is compressed first, then it is cooled in intercooler (2) y circuiting wter. After tht, the compressed ir goes into the high-pressure compressor (3) nd is cooled for the second time in ftercooler (4). In the sturtor, compressed ir is humidified with hot wter which psses through the sturtor. The hot wter quntity increses the mss flow nd the specific het of the working fluid which leds to dditionl power. The use of the recupertor (10) cn recover the turine (9) exhust het for the system. Then the humid ir goes into the comustor (8) nd is fired with nturl gs. Therefter, it inters the turine (9) to do work nd eventully is dischrged into surroundings. 3. Performnces of the System to Study 3.1. Humidity kg kg 1. Humidity is defined s ϕp s d = 0.622, (1) p ϕp s where ϕ mens ir reltive humidity efore entering the sturtor. p s denotes the stem pressure of the sturtor. p is the totl pressure of wet ir in sturtor Specific Work w n. In this pper, specific work nd exergy efficiency s the min evluted performnce indeces re considered. They re illustrted in the following prgrphs. Specific work is clculted s the ctul net power output y per cycle working fluid nd tht cn e presented s w n = W t W c G 0, (2) where W t = G 9 c p,g η t T 8 (1 (π t ) (k 1)/k ), kw. And W cl = G 0 c p, T 1 ((π l ) (k 1)/k 1)/η c, here the W cl is the work consumption of low-pressure compressor. For the work consumption of high-pressure compressor W ch, it is clculted s the low one. Here, W c = W cl + W ch,kw Exergy Efficiency of Cycle η E,x. The exergy efficiency of the system is exhiited s follows: W η t W c E,x =, (3) F xch4 E CH4 + E x,solr where E CH4 is the stndrd chemistry exergy, kj mol 1,ndF xch4 = G 0 f CH4,wheref CH4 is exhiited y (8)nd(9) Solr Energy to Electricity Efficiency (η solr ). To investigte the contriution of the solr energy to the system, the solr energy contriution coefficient is clculted y the following eqution: δ = (W solr W 0 ) ( ) E x,ch4,solr E x,ch4,0 ηe,x. (4) W solr The solr energy to electricity efficiency is tken s n incrementl efficiency, which is lso defined s follows: η solr = (W solr W 0 ) ( ) E x,ch4,solr E x,ch4,0 ηe,x. E x,solr (5) 4. Model of the New System 4.1. Assumption Conditions. In the clcultion model of HAT cycle, to estlish computtion model for HAT cycle, the constrint conditions re needed to otin the stte prmeters. In light of the experimentl technology, more conditions tht required re showed in Tle 1.The ir flow rte (G 0 ) of the low-pressure compressor inlet is 50 kg/s, nd the reltive humidity is set to e 60%. The environmentl temperture is tken s 15 C nd the surrounding pressure is tken s 1r. The exhust temperture of the preheter is higher thn emission cid temperture t lest 10 C. Wter pump efficiency cn e neglected for the wholesystem performnce. Besides, other therml conditions re lso presented in Tle Model of HAT Cycle. In this model, to clculte nd determine the performnce prmeters of the cycle, criticl link is to uild the exergy lnces out every component. Ech component comprises severl equtions for the clcultion of ech stte point prmeters, ut only the exergy lnce equtions re listed s follows Compressor. The exergy lnce eqution cn e expressed for G e x,,in + W c = G e x,,out + I c. (6) Turine. Currently, there is ny unified nd cler definition of turine inlet temperture. Three kinds of definition methods out TIT re used commonly. The first definition is the comustor outlet temperture (t A ). The second one is the gs temperture (t B ) fter the first stge nozzle in turine. The third is tht the verge temperture (t C ) of ll gses which enters the turine. Generlly, the mentioned TIT is usully referred to the second one. In order to clculte conveniently, the first definition is selected in this pper. The exergy lnce eqution of the turine is G 8 e x,8 = G 9 e x,9 + W t + I t. (7) Comustor. The comustion process is nerly n isoric process nd complex. In order to clculte the consumptionoffuelmssflowrte,chemiclrectionis ( fch4 16 ) CH ( d 29 (O N 2 ) + 18 ( ) ( fch4 fch4 CO d ) H 2 O ( f ) CH 4 O N 2. 8 ) H 2 O (8)

3 Photoenergy 3 Solr energy Q A Nturl gs Low-pressure compressor 1 2 T 1 ir inlet Comustor High-pressure Solr collector 8 Turine compressor Q u T u Blender Sturtor Recupertor 4 After-cooler Intercooler Preheter 13 Low lender Exhust Other loss (pip loss) 12 Exhust loss Mke-up wter Figure 1: The flow digrm of the HAT cycle with low- or medium-temperture solr energy. Then, the corresponding energy lnce eqution is expressed s follows f CH4 16 Q m,lhv η r f CH4 16 ΔH m,co 2 +( f CH 4 + d 8 18 )ΔH m,h 2O = ( f ) CH 4 ΔH m,o ΔH m,n 2 f CH4 16 ΔH m,ch ΔH m,o ΔH m,n 2 + d 18 ΔH m,h 2O rectnts. products (9) The mss flow rte of fuel consumption ( f CH4,kg/sir) cn e clculted y the ove eqution. The exergy lnce eqution is defined s G 7 e x,7 + F xch4 E CH4 = G 8 e 8 + I cc. (10) Het Exchnger. Exergy lnce clcultion of het exchnger cn e clculted y the following eqution: G w,in e x,w,in + G,in e x,,in = G w,out e x,w,out + G,out e x,,out + I e. (11) Sturtor. In the sturtor, while the hot wter trnsfers the het nd mss to the compressed ir, the mss flow rte, temperture, nd enthlpy of the humid ir increse. In the outlet of sturtor, the humid ir is nerly sturted. The exergy lnce eqution is G 19 e 19 + G 5 e x,5 = G 20 e x,20 + G 6 e x,6 + I s. (12) Solr Collector. Some equtions of solr collector re given s follows Q U = Q A Q L, ( E x,solr = Q A 1 T ) 0. T sc (13) All gses such s the working fluid of ir, comustion gses, nd stem re supposed s ctul gses, whose thermodynmic properties re influenced y pressure nd temperture nd with FORTRAN progrm for clculting thermodynmic prmeters for different conditions. In ddition, the solr collector temperture is ssumed to e equl to the circulting wter inlet temperture of the sturtor. 5. Thermodynmic Performnce Anlysis 5.1. Anlysis of the Performnces of HAT Cycle. In this study, the min performnces to reserch re humidity, specific work, exergy efficiency of the cycle, nd the solr energy to electricity efficiency, including those of conventionl (reference) nd solr (proposed) HAT cycles. According to the prmeters in different conditions, the rules of two cycles performnce prmeters re studied, which vried with pressure rtio, turine inlet temperture, nd the solr collector efficiency. In this section, in order to revel the vrition lws of the performnce, we choose specific working condition s typicl clculting demonstrtion. The rtio of the collector circulting wter mss flow rte with tht of the internl wter (x)is Vrition of Humidity with Pressure Rtio. Figure 2 shows the vrition of humidity with pressure rtio for solr collector efficiency of 0.65 t different turine inlet tempertures (TITs). As the increse of the pressure rtio, the humidity is incresed. The slope of the solr HAT is

4 4 Photoenergy Tle 1: Assumption conditions. Item Unit Selected vlue Pressure rtio of compressor (π) 3 40 Isentropic efficiency of compressor (η c ) 0.85 Reltive internl efficiency of turine 0.88 Comustor efficiency (η r ) 0.99 Turine inlet temperture (TIT) C Pressure loss coefficient of compressor % 1 Pressure loss coefficient of fter-cooler nd intercooler % 3 Pressure loss coefficient of sturtor % 2 Pressure loss coefficient of recupertor nd preheter % 3 Pressure loss coefficient of comustor % 3 Minimum temperture difference etween outlet humid ir nd inlet hot wter of the sturtor C 5 The temperture difference etween the outlet wter nd ir wet ul of sturtor C 3 10 Mke-up wter temperture C 15 Minimum het trnsfer temperture difference etween gs nd wter (Δt 1 ) C 10 Minimum het trnsfer temperture difference etween gs nd gs (Δt 2 ) C 25 The inlet temperture of methne C 25 Solr collector efficiency Direct solr rdition kw/m The rtio of the collector circulting wter mss flow rte with tht of the internl wter (x) 0.3 greter thn tht of the conventionl HAT. It cn e seen from Figure 2 tht the humidity is incresed much higher for the solr HAT cycle thn tht of the conventionl HAT, nd with the pressure rtio incresing, the enhncement of humidity ecomes gret. For exmple, with TIT = 1100 C, t the pressure rtio of 12, the humidity is 12.44% nd 17.35% for the conventionl HAT nd solr HAT, respectively, which is incresed y 4.91 percent points, while with pressure rtio of 24, it is 16.97% nd 24.18% for the conventionl HAT nd solr HAT cycle, respectively, incresing y 7.21 percents points. In ddition, the humidity chnges lmost the sme vlue with the sme TIT chnge. For instnce, the humidity of the solr HAT is 19.51%, 20.00%, nd 20.6% for TIT t 1000 C, 1100 C, nd 1200 C with pressure rtio of 16, respectively. Owing to the utiliztion of the solr energy tht integrted with HAT cycle, the humidity improves Vrition of Specific Work with Pressure Rtio. The Vrition of specific work with pressure rtio for the cycle in different working conditions is demonstrted in Figure 3. The specific work is incresed gretly with the incresed temperture TIT nd pressure rtio, ut its slope is grdully going down with the enhncement of pressure rtio. In comprison with the conventionl HAT cycle, the specific work is higher for the solr HAT cycle due to the increse of humidity which improves the mss flow rte of the stem in comustor. For exmple, with the pressure rtio of 8 nd TIT of 1100 C, the specific work is kj/kg for the reference cycle nd kj/kg for the proposed cycle, incresing 32.4 kj/kg. And with the increse of pressure rtio, the improvement of specific work increses more; for instnce, t the pressure rtio of 20 nd TIT of 1100 C, the specific work is kj/kg for the reference cycle nd Humidity : Solr HAT : Conventionl HAT Pressure rtio x = 0.3 Ψ = C 1100 C 1200 C Figure 2: Vrition of humidity with pressure rtio kj/kg for the proposed cycle, improving 84.8 kj/kg. In ddition, the TIT hs greter influence on the specific work. At the pressure rtio of 18, when the TIT is chnged from 1000 C to 1200 C, the specific work is incresed y kj/kg for solr HAT cycle reltive to the conventionl HAT cycle Exergy Efficiency. Figure 4 depicts the effectofpressure rtio on exergy efficiency of the cycle t different turine inlet tempertures. At the lower solr collector efficiency,

5 Photoenergy 5 Specific work (kj/kg) Pressure rtio Ψ = 0.65 x = C 1100 C 1200 C : Solr HAT : Conventionl HAT Figure 3: Vrition of specific work with pressure rtio. the cycle efficiency using solr energy is decresed. For instnce, when the solr collector efficiency is 0.65, t the pressure rtio of 12, when the TIT is 1000 C, 1100 C, nd 1200 C, the exergy efficiency of the conventionl HAT cycle is 47.32%, 50.62%, nd 53.44%, respectively, while tht of the solr HAT cycle 46.02%, 49.10%, nd 51.84%. For the exergy efficiency, the solr HAT cycle lso hs n optimum pressure rtio t different TITs similr to the conventionl HAT cycle; however, with the solr energy utiliztion, the optimum pressure rtio will e little incresed. For exmple, while the TIT is 1000 C, the optimum pressure rtio is 8 for the reference cycle nd 9 for the proposed cycle. The exergy efficiency is sensitive to TIT; for exmple, in the condition of π = 16, when the TIT increses from 1100 C to 1200 C, the efficiency improves from 48.95% to 51.75% for the proposed cycle. So the increse of TIT is key fctor to improve the performnce of the HAT cycle The Solr Energy to Electricity Efficiency. The reltionship etween the solr energy to electric efficiency nd the pressure rtio with different TIT is illustrted in Figure 5, ssuming the solr collector efficiency of It cn e seen tht the solr energy to electricity efficiency increses oviously with the increse of pressure rtio t different TITs. However, it is ffected little y the TIT. In Figure 6, it illustrtes the solr energy to electricity efficiency of the HAT cycle with solr energy versus the solr collector efficiency for different TITs nd t given pressure rtio of 16. As cn e known tht, the solr energy to electricity efficiency is enhnced linerly with the increse of solr collector efficiency. With the vlue of solr collector efficiency incresing 10 percent, the solr energy to electricity efficiency improves out 5 percent points. Furthermore, we cn compre the solr energy to electric efficiency in the solr HAT cycle with tht in other dvnced power cycles using solr energy, for exmple, the power cycle in which the solr energy is utilized for the methnol decomposition [12]. At the sme conditions, such s the Exergy efficiency Solr energy to electricity efficiency Pressure rtio x = 0.3 Ψ = C : Solr HAT 1100 C : Conventionl HAT 1200 C Figure 4: Exergy efficiency vrition with pressure rtio Pressure rtio Ψ = C 1100 C 1200 C Figure 5: Solr energy to electricity efficiency vrition with pressure rtio. pressure rtio of 15, TIT of 1200 C, nd solr collector efficiency of 0.62, the solr energy to electricity efficiency in the solr HAT cycle is out 31.2%, while tht is out 30.6% for the power cycle of using solr energy for the methnol decomposition. Through comprison in other conditions, the solr energy to electricity efficiency in the solr HAT cycle is lmost greter. According to the nlysis, the solr energy to electricity is improved due to the solr energy integrtion with the HAT cycle Exergy Anlysis of Components in the System. The most commonly used method for nlysis of n energy-conversion

6 6 Photoenergy Tle 2: The dt of every stte point prmeters for ht cycle with solr energy. Condition π = 14, TIT = 1100 C, x = 0.3 Point Enthlpy Entropy Pressure Temperture Flow rte chnge chnge (MP) ( C) (kg/s) (kj/ kg ) (kj/(kg K)) Exergy (kj/ kg) Totl exergy (kw) Solr energy to electricity efficiency Pressure rtio Solr collector efficiency (Ψ) 1000 C 1100 C 1200 C Figure 6: Solr energy to electricity efficiency vrition with solr collector efficiency. process is the first lw of thermodynmics. However, there is incresing interest in the comined utiliztion of the first nd second lws of thermodynmics, such s concepts s exergy efficiency nd exergy destruction. The exergy nlysis method is providing n indictor tht points which direction efforts should e concentrted to improve the performnce of the thermodynmic systems [15 17]. The exergy nlysis method cn find the useful work nd the degree of energy utiliztion qulittively nd quntittively. Therefore, it not only cn estimte the efficiency of the system ut lso offer the trget of improving equipment nd sving energy y finding the wek links of the mximl exergy loss [17 20]. In order to otin the utiliztion sitution of the energy in system, the exergy nlysis will e crried out in certin conditions of the system. Under the conditions of π = 14, TIT = 1100 C nd the rtio of solr collector circulting wter mss flow rte with tht of internl circulting wter (x = 0.3), the therml prmeters of the solr HAT re shown in Tle 2. In Tle 3, it presents the exergy efficiency comprison, the exergy loss, s well s the exergy loss percentge of every component in cycles. Additionlly, Figure 7 shows the comprison of exergy loss out every component in the cycles. We cn see tht the gretest exergy loss in the cycle occurs in the comustor ecuse of chemicl rection tht mkes lrge temperture difference etween the rectnts nd the comustion gses. The comustor exergy loss percentge is out 54.60% for the conventionl HAT, nd tht is chnged to 47.71% for solr HAT due minly to the increse of

7 Photoenergy 7 Tle 3: Exergy destruction nd exergy efficiency of components. Cycle Conventionl HAT Solr HAT Condition π = 14, TIT = 1100 C π = 14, TIT = 1100 C, x = 0.3, ψ = 0.65 Components Exergy Loss (kw) Exergy efficiency ω 1 (%) Exergy loss (kw) Exergy efficiency ω 2 (%) (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) Totl % % Totl Exergy Input (kw) Solr Exergy Input (kw) CH 4 Consumption (kg/s) Specific Work (kj/kg) Solr Energy to Electricity Efficiency (%) Exergy Efficiency of system (%) Solr Contriution Coefficient (δ) (%) 4.83 Exergy loss (%) (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) Solr HAT Conventionl HAT (1) LPC (2) Intercooler (3) HPC (4) After-cooler Components (5) Blender (6) Low lender (7) Sturtor (8) Comustor (9) Turine (10) Recupertor (11) Preheter (12) Exhust loss (13) Solr collector (14) Other loss Figure 7: Exergy losses rtio of components in totl exergy loss. the gs flow rte nd its exergy output. The exhust loss, the regenertor, nd the sturtor ll occupy lrge proportion of exergy destruction. However, owing to the increse of stem in the exhust gs crrying off prt of energy, the proportion of exhust exergy loss in the solr HAT cycle is incresed to 17.68% compred to the conventionl HAT of 15.22%. Also, the results revel tht the exergy loss in solr collector is out 8.14%. For the two cycles, the exergy losses in turine; the sturtor nd the recupertor ll occupy nonnegligile prts. The exergy efficiency of the two cycles is out 50.47% nd 49.04%, respectively. Furthermore, the fuel mss flow rte consumption of the solr HAT is little higher thn the conventionl HAT due to the dditionl circulting wter which comes from the collector. On the contrry, the specific work is much greter. Moreover, the system of HAT cycle which uses solr energy improves the exergy efficiency in comustor nd tht provides helpful guidnce for improving the design of the relted components. 6. Conclusions Minly y using the exergy nlysis method, this pper hs studied the vrition lws of the performnce of the HAT cycle with solr energy s the ssistnt het source. According to the otined results from the thermodynmic nlysis of the solr HAT nd the conventionl HAT, they show tht some performnce prmeters increse gretly y utilizing the solr energy, such s humidity, the cycle s specific work, nd the solr energy to electricity efficiency. Compred to

8 8 Photoenergy the pure solr plnts, this method is useful for improving the performnce of the utiliztion efficiency of solr energy. In ddition, the lrgest exergy loss of the components in cycle is comustor. In comprison with the conventionl HAT, the exergy loss in comustor is decresed for solr HAT due to the stem flow rte incresing. It is lso found tht the exhust gs, the exergy losses in sturtor, recupertor, nd turine lso occupy lrge proportion prts. Therefore, we cn find out the wek link in energy utiliztion of the system. Through the nlyticl results, the utiliztion of solr energy comined with HAT cycle cn provide n importnt direction for the future of the dvnced power cycle using fossil fuels nd renewle energy. Nomenclture nd Suscripts Nomenclture C p : Specific het (kj/(kg K)) d: Humidity (kg/kg) E CH4 : The stndrd chemistry exergy of methne (kj/kg) E x,ch4,solr: Nturl gs exergy with solr energy (kw) E x,ch4,0: Nturl gs exergy without solr energy (kw) E x,solr : Exergy of solr energy (kw) e x : Exergy (kj/kg) f CH4 : Consumption of nturl gs mss flow (kg/s ir) F xch4 : Consumption of nturl gs mss flow (kg/s) G: Working fluid flow (kg/s) G 0 : Air mss flow of the low-pressure compressor inlet (kg/s) I: Exergy loss (kw) p: The totl pressure of sturted wet ir in sturtor p s : The stem pressure of the sturtor Q U : Energy output of solr collector (kw) Q A : The collector sorption of solr energy (kw) Q L : The solr energy dissipte for surroundings (kw) Q m,lhv : Lower heting vlue of methne (kj/kmol) T 0 : Surrounding temperture (K) T sc : Solr collectortemperture(k) W t : Work output y turine (kw) W c : Work input y compressor (kw) w t : Specific work of turine (kj/kg) w n : Specific work of cycle (kj/kg) W solr : Net power with solr energy W 0 : Net power without solr energy x: The rtio of the collector circulting wter ΔH m,x : mss flow rte with tht of the internl wter Enthlpy of products nd rectnts in comustor (kj/kmol) ϕ: The reltive humidity of ir efore entering the sturtor ψ: Solr collectorefficiency K: Aditic exponent η E,x : Exergy efficiency of solr HAT cycle η e,x : Exergy efficiency of conventionl HAT cycle η solr : Solr energy to electricity efficiency η r : Comustor efficiency δ: Solr contriution coefficient π t : Expnsion pressure rtio of turine ω 1 : Percentge of the exergy loss of every component to totl exergy loss in reference HAT cycle ω 2 : Percentge of the exergy loss in every component to the totl exergy loss of solr HAT cycle. Suscripts : Air w: Wter in: Inlet out: Outlet g: Gs c: Compressor t: Turine e: Het exchnger cc: Comustor s: Sturtor sc: Solr collector. Acknowledgment The uthors re profoundly grteful for the eductionl fund y the Chin University of Petroleum, Beijing. References [1] Y. Wng, Y. Liu, nd W. Tin, Reserch progress on hyrid PV/therml solr system, Solr Energy Journl, vol. 26, no. 5, pp , [2] D. Zeng, Technology progress in solr therml power genertion, Gnsu Sciences, vol. 8, no. 3, pp , [3] M.-L. Yng, X.-X. Yng, R.-M. Lin, nd J.-L. Yun, Solr energy-sed therml power genertion technologies nd their systems, Therml Energy Power Engineering, vol. 23, no. 3, pp , [4] J. Yun, Integrtion reserch on novel system of solr energy het utiliztion, M.S. thesis, Grdute University of Chinese Acdemy of Sciences, [5] S. Jio, Thermodynmic nlysis for humid ir turine cycle, Gs Turine Technology, vol. 8, no. 2, pp. 1 11, [6] L. Wng nd H. Song, Development nd sttus of humid ir turine cycle, Energy Sving nd Environment Protection, no. 8, pp , [7] M. Jonsson nd J. Yn, Humidified gs turines review of proposed nd implemented cycles, Energy, vol. 30, no. 7, pp , [8] P. Schwrzözl, R.Buck, C.Sugrmen, et l., Solr gs turine systems: design, cost nd perspectives, Solr Energy, vol. 80, no. 10, pp , [9] R. Lin, H. Jin, nd R. Ci, Totl energy systems nd energy cscde utiliztion principle of gs turines, Gs Turine Technology, vol. 21, no. 1, pp. 1 12, 2008.

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10 Medicinl Chemistry Photoenergy Orgnic Chemistry Interntionl Anlyticl Chemistry Advnces in Physicl Chemistry Crohydrte Chemistry Quntum Chemistry Sumit your mnuscripts t The Scientific World Journl Inorgnic Chemistry Theoreticl Chemistry Spectroscopy Anlyticl Methods in Chemistry Chromtogrphy Reserch Interntionl Electrochemistry Ctlysts Applied Chemistry Bioinorgnic Chemistry nd Applictions Chemistry Spectroscopy