SCIENCETECHNOLOGYl
HE THONG MAY LANH MINI L A M M A T CHO QUANG TRd DAU Tir DAN HONG NGOAI
A MINI REFRIGERATOR SYSTEM - USED TO MAKE A RESISTANCE PHOTOVOLTAIC TO BE COOLING BY INFRARED LIGHT
Cu Huy Thanh, V u Q u o c T o a n
Tom tat
Bai bao trinh bay nhifng phan tich ve nguydn l)j lam viee, dac diem cua hieu feg Joule -Thomson va hieu ling ong xoay; lam ca sd cho viec lira chpn nguyin ly, ket cau cho he thong lam lanh mini lam mat cho quang trd dau tudan hong ngoai. Ket quS nghien cUu ve ket cau va gi^i ma ve mat cdng nghe cua cac thiet bj cCing loai cho phep ap dung de thiet ke, che tao h i thong nay tai Viet Nam.
Ttf khda: may lanh, lam mat, quang trd, dau ty dan. Joule -Thomson, dng xoay
Abstract
This paper presents an analysis ofthe working principle and characteristics about Joule - Thomson and Ranque - Hilsch Vortex Tube (RHVT) and is a the basis for seleefing the principle, structure for a mini refrigerator system used to make a resistance photovoltaic to be cooling by infrared light. The results of structure and decoding technology of equipments having the same level show that the application to design and manufacture of this system In Vietnam are can be carried out.
Keywords: refrigerator, cooling, photovoltaic, resistance, Joule - Thomson, Ranque - Hilsch Vortex Tube (RHVT)
PGS.TS. CiJ Huy Thanh -Hoc vien Ky thuat Quan sU ThS. Vu QuocToSn -Vien Cong nghe, Tong cue Cdng nghiep Quoc phdng Email: [email protected]
Ngaynhanbai: 15/01/2014 Ngaydiap nhan dang: 21/03/2014
1.0ATVANDE
May lanh mini lam mat cac chi tiet dac biet duac sCrdung nhieu trong ITnh vuc cong nghiep, y te, ky thuat hang khong, ten ICra,... nhang ket q u i nghien cuXi v^ thi^t bj nay tai Viet Nam con rat han che. Day la ITnh vtfc cong nghe cao, dac biet nen ft defOc cong bo rong rai.
Ten ICfa phong khong tam thap (PKTT) la mot trong nhiJng loai vu khf daoc nhieu quoc gia trong khu vac va tren the gidi quan tam nghien cau che tao; vdi ly do co do chinh xac cao.
kha nang sat thUdng Idn, de sa dung va tinh co dpng cao. Tren to hop nay, lap dau t u dan sCf dung quang trd du<?c tam lanh sau tdi nhiet do -196°C; de lam lanh eho bp phan nay co the stf dung nhieu nguyen ly khac nhau, yeu cau kich thude p h l i nh6 va hieu qua lam lanh cao trong thdi gian ngan.
Mac du ten ICTa PKTT do Nga ehe tao da cd nhieu cai tien nhung cho tdi nay cum thiet bi lam lanh cho quang trd dau t a dan v i n ducfc che tao theo nguyen ly va thiet ke cua to hdp ten laa 9K34.
Hien nay, nhii'ng ket qua nghien cdu ve may lanh mini lam mat cho quang trd dau tudan khong duoc cong bova ehuyen giao, luon dupe coi la bi quyet cdng nghe; day la cum thiet bi khd che tao doi hdi edng nghe va ky thuat cao.
Vi vay, viec nghien cau ve nguyen ly, thiet ke va cong nghe che tao cum may lanh nay la nhiem vu rat quan trong, gdp phan vao hoan thien thiet ke, cong nghe che tao ten laa PKTT tai Viet Nam.
Bai bao trinh bay nhCfng ket qua nghien eUu trong giai ma nguyen ly lam viec, ket eau cCia he thdng lanh mini va mdt so ket qua nghien eUu trong thiet ke, ehe tao san pham nay.
2. H | THdNG LANH JOULE THOMSON VA Hl£U l^NG 6 N G X O A Y Lam lanh la mpt yeu cau rat pho bien trong ky thuat cung nhu trong ddi song; lam lanh sa dung chu trinh ngape chieu la chu trinh cd ehdc nang chuyen nhiet nang tif nguon cd nhiet dp thap den nguon ed nhiet do cao nhd su ho trp cua nang lUpng ben ngoai.
Chu trinh ngUpc chieu ed hai loai la ehu trinh cua khi ly tUdng va ehu trinh eija khf thUc; ehu trinh cua khi ly tadng it ducrc sCt dung vi cd hieu qua truyen nhiet khdng cao, edng kenh. Chu trinh ngUpc chieu khi thac don gian gom 4 thiet bj chinh: Buong [anh con dUcJc gpi la binh bay hoi, may nen, binh lam mat
So 2 1 . 2 0 1 4 - T a p dii KHOA HOC&CONG NGHE 143
I^K^g^SScdNG NGHL
cdn duac gpi la binh ngUng tu. van tiet lau. Tuy nhien, theo yeu cau cua cong nghe lanh, thudng cd eae dang eai tien nhu [1,2]:
- Chu trinh nhieu mdc lanh vdi mot may nen va mot binh ngUng;
-Chu trinh nhieu budng lanh, nhieu may nen;
- Chu trinh hda Idng khf;
- Chu trinh s i n xuat tuyet CO^...
Chu trinh hoa
I
Idng khi duoc dungtrong tradng h p p 1^^" t h d i gian can lam lanh ngan, khong t h u d n g xuyen va neu trang bj may lanh thi khdng sd dung het eong suat;
ngadi ta t h u d n g diing the Idng eua cae chat khi CO nhiet do sdi rat thap dUdi Hinh 1. Thiet ap suat khi quyen.
bl lam mat cua Vi d u , oxy cd nhiet Honeywell Hymatic d p sdi d ap suat khf quyen k h o i n g 90K, nito (77,4K), neon (27,3K), hydrogen (20,4K), helium (4,2K),... cac chat Idng nay dOng trong
Hinh 2. Sa do cau tao cua ong xoay RHVT
JU
Hinh 3.Tach dong khf ndng vit lanh cua dng xoay RHVT
cae binh dac biet gpi la Dew/ar. Khi sCr dung phucJng phap lam lanh nay, yeu cau dat ra la phai hda long khf, cd 3 chu trinh hda khf Idng dape d i i n g la:
p h a o n g phap Pietett, phUOng phap Linde va phUong phap Claude.
Khi hoa Idng dupc sa d u n g de iam mat eho cac dau t u dan eija cae thiet bj quan su. Td nam 1955 Honeyw/ell Hymatie da di tien phong trong cong nghe lam lanh sau cho cac dng d y n g quan sU bang each sd d u n g he t h o n g lanh Joule - T h o m s o n . DU(3c phat trien bdi James Joule va Lord Kelvin trong naa cuoi eua the ky 19, he t h o n g lanh Joule - Thomson sif dung cac ky thuat hda Idng k h i ap suat cao t h d n g qua m p t van tiet luu [10].
Dieu chinh lam lanh sao cho t d i da hoa thdi gian sd dung cho m o t khoi lUdng nhat djnh khi dape lUu trd, cd t h e kiem scat chinh xac nhiet dp hoat d d n g cua chung de d i m bao su on djnh cua nhiet do be mat vdi thay d o i t o i thieu.
Mgt ca cau dieu khien chat Idng ket ndi vdi m p t thiet bj dieu khien d o n g chay trong o n g lam lanh Joule - T h o m s o n , se dam bao eho luu lapng k h i chfnh xac de tai nhiet cCia dau t u dan. Hien nay,
"the he t h a 4 " c u a may lanh s a d u n g he t h o n g lanh Joule - Thomson da t d i uu dupc su on dinh nhiet d p cua dau t a dan, eiing v d i viec giam thieu tieu t h u khf hda long [10].
He t h o n g lanh Joule - Thomson dupe thiet ke de chiu dape mdi t r u d n g khac nghiet nhat t r o n g chien dau, bao g o m ca t l i trpng va d a p cUc, lUc t r p n g t r a d n g va toe d p chuyen d p n g cao; nhOng tinh nang cCia he
t h d n g lam lanh sau da 3uac ehiJng m i n h . Vdi nhieu bien phap dac bietd^
tdi Uu hieu suat, Honeywell Hymatic gidi t h i e u he t h d n g lam lanh sSucothe bao q u l n dUoc m d t each an toan trong nhieu nam, lam lanh dUOc den -173°C t r o n g ehUa day m d t giay. Nhiet dfl lam lanh t h a p nhat cua Honeywell Hymatic Joule - Thomson c d the dat dupc la -243°C (hinh 1) [10]. Hinh 1 la hinh dang thiet bj lam mat cCia Honeywell Hymatic.
d n g xoay dupc phat mmh bdi m d t nha vat ly ngUdi Phap Georges!
Ranque vao nam 1933 [3]. Vi khong cd hieu q u i rd rang nen bSng sang che va y t a d n g da bj " b o quen"trong nhieu nam. Cho den nam 1947, ky sU ngudi Dac Rudolf Hilsch da sda d6\ thiet kl cCia d n g [4]; ke t d do, nhieu nha nghien cdu da c d gang t i m each de toi Uu hoa hieu q u i cCia nd. Hien nay, van chua c6 giai thich t h d n g nhat ve sutach nhi&t xuyen t a m caa o n g xoay. He thdng o n g t a o xoay cua Georges J. Ranque va Rudolf Hilsch g p i la Ranque - Hilsch Vortex Tube (RHVT){hinh 2, 3) [5],
O n g xoay RHVT la m p t thiet bi cho p h e p tach k h o n g k h i ndng va lanh khi khi nen c h l y tiep tuyen vao buong xoay qua cac vdi p h u n . Hieu dng d i e biet t r o n g o n g xoay la khi cho mpt dong khong khf t h o i tiep tuyen vdi thanh t r o n g cua o n g , v u o n g goe vdi true ong thi nhiet d p d t h a n h d n g tang len trong khi nhiet d o d t a m o n g g i i m xuong; khi dat 1 t a m ehan sat d d n g thoi tiep tuyen thi g i o lanh se di qua dpc theo tam cua o n g , cdn g i d ndng di theo hUdng ngape lai, xoay sat thanh dng {hinh 3).
Tach d d n g lanh va ndng bang each sil d u n g cac nguyen tac cua ong xoay cd the dupc a p d u n g c h o cac thiet bi lam mat, rat p h u h p p v d i cac Ong dung c6 yeu cau dPn g i i n , g o n nhe va khong gay o n [5],
Co hai loai caa o n g xoay, deu dang d u p c s d d u n g t r o n g nganh cdng nghiep (hinh 4, 5). Pho bien hari c l ia
441 Tap diiKHOA HOC&CONG N G H N S d 2 1 . 2 0 1 4
SCIENCETECHNOLOGYl
Khirao /
Xhi-BK,
M a n g d i d a
Hinh 4. Ong xoay dong chay ngifoc chieu
Hinh 5. flng xoay dong chay cimg chieu
Van &ka k h i ^ ^
thue nghiem toi Uu hinh hpc cua he thong xoay RHVT [7]. Takahama (nam 1960) da cd nhdng nghien cOu ve he thong dng xoay RHVT, ong chi ra rang: dng xa cua cac vdi phun t d 0,5 - 1 mm, cdng suat lam lanh phu thuoc vao cau tao hinh hoe cua he thong ong xoay RHVT.
Paruleker (nam 1961) da thiet ke mdt ong xoay ngan hinh ndn [8]. Ong thay rang, ket eau be mat ben trong eCia ong cd anh hadng den hieu suat lam lanh; thiet ke cua buong xoay va cac vdi phun dau vao la rat quan trpng, cac vol phun dau vao nen cd mdt hinh dang xoan 6c Ac si metva mat cat ngang cua nd phai 1 - 6ng mdy; 2 • Loi; 3-Binh chda; 4-De quang trd; 5-6ng ndi dape khfa ranh. Ong Hinh7.Maylanhminisi]rdunghieuungJoule-Thomsonvahieuiingongxoan phat hien ra rSng
cac ong xoay vdi Khinoi^ra
Hinh 6. Ong xoay hinh non
dng xoay ddng chay ngiipc chieu (hinh 4), khong khf ndng thoat ra t d phfa ben kia cua ong dape dieu khien bdi van hinh ndn, khong khf lanh thoat ra qua mpt lo ben canh cac dau vao. NgUdc lai, ong xoay ddng chay cung chieu khdng cd 16 khong khi lanh ben canh dau vao;
thay vao do, khdng khi lanh di ra thong qua mpt 16 hinh khuyen dong tam nam d van hinh ndn (hinh 5). Day la loai ong xoay duac sd dung trong cac dng dung cd yeu c l u tdi Uu ve khdng gian bo tri, nhung doi hdi chi phi thiet bi eao [5].
Westley (nam 1955) da nghien cdu
mpt gdc hinh ndn khoang 2 - 3 dp cd hieu suat lam lanh Idn hc^n cac dng xoay hinh tru khoing 20%-25% (hinh 6).
Nghien cdu cua Borisenko (nam 1968) cho thay gdc ndn tdi Uu cho dng xoay hinh ndn la 3 dp [7]. Piralishvili va Polyaev (nam 1996) gidi thieu mdt loai mdi cua dng xoay [8]: Mach ddi dng xoay, vdi mot dng hinh ndn de cai thien hieu suat; d cda ndng, trong trung tam cOa cac van dieu khien, cd mpt 16 cho phep phan hoi khf ve dng xoly; khf p h i n hoi cd cung nhiet dp nha khf dau
vao nhUng vdi ap suat thap. Vdi thi^t ke nay, cdng suat lam mat cua he thong tang va hieu qua hoat dong cOa ong xoay duoc cli thien,
Hieu suat cua mdt chu trinh lam lanh Joule -Thomson vdi mpt mdi chat tmh khiet co the duac cli thien dang ke bang each ap dung mot dng xoan (dng mao dan). Trong hinh 7, gidi thieu he thong lam mat quang trd sd dung hieu dng Joule -Thomson va hieu dng ong xoan; khf vdi ap suat cao dupc dUa vao may lanh t d binh nen khi thdng qua dng noi (5) di qua Ipc vao dng xoan (1) dupc quan tren Idi (2), sau khi ra khdi 16 hep (van eCia ong) khf gian nd va n h i i t dp giam, de cua quang trd dape lam mat.
3. MAY LANH MINI L A M M A T QUANG TRd D A U TLT D A N
Vdi yeu cau nhd gpn de dam b i o kha nang tac chien cua ten Ida PKTT, viec lUa chon he thong may lanh mini ed ehu trinh hda Idng va sd dyng mdi chat nito la phu hpp; cd the ket hpp he thong lanh Joule - Thomson vdi hi&u dng ong xoan de nang eao hieu suat lam lanh. Tren ca sd tham khio may lanh mini eiia ten Ida Igia (hinh 8,9), da thiet ke may lanh mini lam mat dau t u dan quang trd ten Ida PKTT nhU tren hinhIO, 11,12,13.
De may lanh (1) lam bang vat lieu SUS 316 ed buong chda khdi Ipc khi.
Than may lanh (2) lam bang vat lieu SUS 316 duoc ket ndi vdi de may lanh bang he thong vit va chop bang han ket ndi. Toan bp he thdng dng xoay nam trong than may lanh; he thong ong xoay (3) gom 4 dng day lam bang hpp kim CuNi duoc quan xoay quanh true vdi gdc 2°. Chdp may lanh (4) lam bang vat lieu SUS 316 dupc gan vdi dau vdi phun. Cpc djnh vj may lanh lam bang vat lieu SUS 316 dape gan vdi de, diing de ed djnh loi; Idi may lanh (6) lam bang vat lieu AG-4B, ed dang hinh cdn 4°. He thdng dng day tao xoay dape quan quanh Idi; ong day tao xoay
So 2 1 . 2 0 1 4 •TapdiiKHOAHOC&CONGNGHE 145
EIEHffigCONGNGHl^
Hinh 12. Ban ve 3D cat bo may lanh mini tren ten lu^ PKTT
(NitP long sdi 6 nhi&t d p -ige^C). Ket qua nhiet d p m o i t r a d n g xung quanh dau voi p h u n khi d o la -196°C.
- Che tao m i y lanh mini ten liJa PKTT: Tren cP sd nguyen 1^ lam viecvi ban ve thiet ke he t h o n g , da ch^tao t h a n g h i e m m d t so chi tiet quan trong;
day la cac chi tiet khd gia cong (kfeh t h a d e nhd, hinh dang phUc tap, vat l i ^ dac biet...), d d i hoi p h l i sddungefing nghe cao va phdc tap; cac chi tiet difoc t r i n h bay n h u tren hinh 14,15.
4 . K^T QUA
Viec lua chpn h^ thdng m^y lanh mini cd ehu t r i n h hda Idng v l sCfdung mdi ehat la nitP la phii hpp; dap iJng daoc yeu cau can lam lanh khong dcii {khoang 9 -H 11 s), khong thadng xuy^n, n h d g p n de d i m b i o k h i nang t^c chien cua ten Ida PKTT.
I-Be; 2- Than;3 - 6ngxodn, 4- Chdp 5 - Coc dinh vi, 6 - idi; 7 - 6ng ddy ddu ra Hinh 10. So do cau tao may lanh mint ten Ilia PKTT
d i u ra (7) lam b^ng h p p kim CuNi cd kich thude n h d hdn he t h d n g dng day, dUdc quan hinh Id xo, m p t dau ndi vdi 1 trong he t h d n g 4 d n g day, mdt dau ndi vdi vdi phun.
- Chde nang eOa m i y lanh mini trong ten Ida PKTT: De bam bat muc tieu, ten Ida PKTT cd sddung quang trd kenh chinh nhan tin hieu hong ngoai t d muc tieu phat ra. Tin hieu hdng ngoai t d muc tieu qua quang trd kenh chinh thanh tin hieu dieu khien ten Ida bam theo muc tieu. Tuy nhien, quang trd kenh chfnh chf hoat dong dape vdi tin hieu hong ngoai khi nd duoc lam lanh tdi -196''C. Vt vay, m i y lanh mini ed chde nang lam lanh de quang trd kenh chinh xudng -196''C khi ten Ida hoat ddng.
- Nguyen ly hoat ddng cua may lanh mini trong ten Ida PKTT: Khi nito vdi ap suat den 35MPa, ed do sach cao dupc
Hinh 13. Ban ve 30 cum van may lanh mini tren ten b o m vao he t h o n g d n g dan t d n g u d n mat dat qua he t h d n g van di vao may lanh qua he t h d n g Ipc, rdi qua he t h o n g dng day quan hinh xoay; k h i nitcJ vdi ap suat eao di vao buong xoay, he t h d n g dng xoay. Tai day xuat hien hieu d n g lam lanh d o xoay lam eho nhiet d o cua khi nito giam x u d n g nhanh chdng.
Tiep theo khi nito ed ap suat eao nhiet d p giam di ra dau voi p h u n , tai dau voi cd ap suat thap (ap suat k h i quyen) khi d o eae phan t d khi gian n d d o t ngdt dSn den nhiet d p khdi khf nito g i i m rat nhanh (theo hieu dng Joule - Thompson). Nhiet d p ciia khoi khf nito g i i m xudng den nhiet d p hda Idng cua nito, khi d o khdi khf ni t o hda Idng. Nito Idng d trong dieu kien nhiet d o m o i t r u d n g nhanh chdng soi va bay hai
Hinh 15. Loi may lanh mini tren ten lijla PKIT 6 n g xoay RHVT la m o t thiet bi cho p h e p tach khdng k h i nong va lanh khi khf nen mdi c h i t c h l y tiep tuy^n vSo (Xem tiep trangSIJ
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a) Su do mach tach song Hinh 8. Mach tach song
dyng AD8009, la mpt IC khueeh dai linh hoat cd tdc dp khueeh dai sieu cao, rat ly tudng dijng trong khueeh dai xung
Mach khueeh dai trung tan dat he sd khueeh dai 30 dB d tan sd 60 MHz.
Bp tach sdng pha dape thiet ke bang phan mem Protel99 SE3. Mach
1 ta
tach sdng pha (hinh 8) cd ngudn nudi la+12V, bien the dupe dieu ehinh d tan sd cdng hUdng la 60 MHz. Ldi ra cua bd tach sdng, chung tdi thu dUOc xung thdng tin (hinh 8b), cae thdng sd cua tin hieu thdng tin taong ddi trung thac vdi tfn hieu ban dau.
Bd dieu khien he sd khueeh dai ty ddng theo thdi gian, vl sU kho khan ve linh kien thiet ke chung tdi xin dupc trinh bay trong nhdng cdng bd tiep theo.
4. KET LUAN
Chung toi da che tao thanh cdng cae khdi cO b i n trong he thdng thu tin hieu d bang tan L. Viec nghien cdu hoan ehinh he thdng se md ra dng dyng eho khdi thu nhan tin hieu tra Idi trong he thdng nhan biet chu quyen qudc gia.
Phan bien khoa hoc: PCS .TS Hoang Nam Nhat
T/hl UEU THAM KHAO
[1]. Nguyen Thi Xuan My, He thong thong tin, dan diidng, giam sat phuc vu qutin ly khong lifu CNS/
ATM, Tap chi Buu chinh Vien thong, 27/07/2007, [2] GS.TSKH Phan Anh, Giao trinh lythuye'tva^
thuat sieu cao tan, Bp mon Thong tin vfi tuyen, Khoa fiien tli -Vlin thfing, TrUcing Dai hoc Cong nghe.
[3]. David M.Pozar, Microwave engineering, John Wiley & Sons, Inc.
[4]. W. Alan Davis, Radio Frequency Qroiit Design, John Wiiey & Sons, Inc (2001).
[5]. ICAO, Air Trairfic Control Senrices, Flight Information Service and Alerting Services, IJ Edittion, July 2001 (2001).
HE THONG MAY LANH MINI...
budng xoay qua cac vdi phun, Sd dung hieu dng cua dng xoay cho ele thiet bi lam mat, rat phu hpp vdi cac dng dung cd yeu eau la don gian, gpn nhe va khdng gay dn.
Da nghien cdu tim hieu dupe nguyen ly lam viec cua m i y lanh mini lam mat cho dau tU dan quang dien trd cua ten Ida PKTT, lam ea sd cho viec thiet ke, che tao san pham tai Viet Nam.
Ket qua ehe tao t h d nghiem mdt sd chi tiet quan trong eiia he thdng cho thay cd the lam ehu dUcrc edng nghe che tao he thdng lam lanh nay.
Nhdng ket q u i nghien cdu may lanh mini cho phep md ra djnh hudng nghien cdu dng dung he thdng lanh Joule - Thompson va hieu dng xoay
eho eae thiet bi lam lanh trong edng nghiep, he thdng b i o dn. may lanh, may bay,ten Ida...
Phan bien khoa hoc: TS. Nquven Tuan Hieu
TAI UEU THAM KHAO
[1]. Pham Le Dan, Bui Hal, Nhiet dong hoc ky thuat, NXB Khoa hoc ky thuat, Ha Nfii, 2005.
[2]. Nguyen Mc Lgi, Pham Van Tuy, Ky thuat lanh CO scf, NXB Giao due, 2006.
[3]. J.E. Lay. An experimental and analytical study of vortex-flow temperature separation by superposition of spiral and axial flow. Part ll. Trans.
ASMEJ. Heat Transfer, 81:213- 222, Aug, 1959.
[4], H. Takahama and H, Yokosawa, Energy separation in vortex tubes with a divergent chamber.
(Tiep theo trongm,
Trans.ASME,J.HeatTransfer,103:196-203,(i/Iay19Bl.
[5]. Giorgio De Vera, The Ranque-Hilsdi Vortex Tuhe, http://berkeley,academia.edu. May 10,2010.
[6]. P.K. Singh, R.G. Tathgir, D. Gangacharyulu, and G S. Grewal, An experimental perfor - mance evaluation of vortex tube, Journal of Institution of Engineers (India), 84:149-153, Jan. 2004.
[7]. M. Kiirosaka, Acoustic streaming in svjitling flow and the Ranque - Hilsch vortex-tube effect,!
Fluid Mech,124'139-172,1982.
[8]. Gutsol. The Ranque effect. Physics-Uspekhl, 40(6)-639-658,1997,
[9]. E. H. AHTOHOB, B E. Vintm, E. A. KoneHiffl, K).B fieTpoBCKHii, A. M. MnpHOB, VcTpoiieTBa AHfl oxna)KAeHiin npHeMHHKOB ii3ny>teHMfl, H^fl.
((MauiHHoerpoeHHeii.JleHHHrpafl. 1969 [10]. http://www.hellotrade.com/honeywell- hymatic/joule-thomson-coolers-cryostats.html
501 TapdiiKHOAHOC&CONGNGH|. So 2 1 . 2 0 1 4
