NATIONAL
INSTITUTE for LASER, PLASMA and RADIATION PHYSICS LABORATORY of SOLID-STATE QUANTUM ELECTRONICS |
|
TIP PROIECT: PROIECTE DE CERCETARE EXPLORATORIE - PCE 2021
TITLU: Aprinderea Amestecurilor Combustibile Hidrogen/Aer cu Dispozitiv Laser Compact, Comutat Pasiv Nd:YAG/Cr4+:YAG
de Tip Bujie Laser;
IGNI-HY-LASER
TITLE:
Ignition
of Hydrogen-Air
Mixtures by Compact, Passively Q-Switched Nd:YAG/Cr4+:YAG Spark Plug-Like
Laser Devices;
IGNI-HY-LASER
___________________________________________________________________________________________________________________________________________________________________________
PROJECT
DURATION:
01 June 2022 - 30 November 2024
DURATA
PROIECTULUI: 01
Iunie
2022 - 30 Noiembrie 2024
PROJECT LEADER:
National Institute for
Laser, Plasma
and Radiation
Physics, Magurele 077125, Ilfov, Romania
CONDUCATOR PROIECT:
Institutul
National de
Cercetare-Dezvoltare pentru Fizica Laserilor, Plasmei si Radiatiei,
Magurele 077125, Ilfov, Romania
Contract value: 1.050.000 lei
Valoare contract: 1.050.000 lei
The research team: PAVEL Nicolaie, PhD CS I
Echipa de cercetare: GRIGORE Oana-Valeria, PhD CS III
STANCIU George, PhD
CS III
CROITORU Gabriela, PhD CS
BRANDUS Catalina-Alice, PhD CS
CRACIUN Alexandru, PhD student ACS
VOICU Flavius-Marian
CS
___________________________________________________________________________________________________________________________________________________________________________
●
For
its development, human society needs energy, and combustion is the
major
process by which this energy is obtained. On the other hand, human
development
has also led to awareness of the negative effects that energy
production has on
the environment. Consequently, various methods of improving combustion
are
sought for the efficient use of current resources; also, new resources
are
considered to be used in order to obtain clean energy. In the case of
internal
combustion engines, laser ignition has been seen as an alternative
solution to
increase efficiency and decrease specific emissions. Our research group
has
world-renowned results in laser ignition of gasoline-air mixtures in
real car
engines. Also, we recently reported the ignition of methane-air
mixtures, using
laser ignition at several points. On the other hand, studies and the
use of
hydrogen have seen a strong development in recent years. Within this
project
proposal the conditions for laser ignition of hydrogen-air mixtures of
various
concentrations and at different pressures will be determined.
Spark-plug like
laser devices will be used for ignition, emitting a single pulse or a
train of successive
pulses. Furthermore, a theoretical model for describing laser ignition
in both
these regimes will be developed. It is worth to mention that this topic
fits
within and corresponds to the European hydrogen strategy, established
in April
2021 by "The Hydrogen Act".
● In
this project the conditions for laser ignition of H2-air
mixtures
will be investigated. The project has three main objectives, as follows.
O1. High-peak
power, passively Q-switched Nd:YAG/Cr4+:YAG
laser with pulse-train
emission;
O2. Ignition
of H2/air mixtures in a static, constant-volume
chamber;
O3. Modeling
of the train-pulse laser ignition process.
RESULTS
___________________________________________________________________________________________________________________________________________________________________________
1. ETAPA I. Iunie -
Decembrie 2022
-
A fost
determinata configuratia optica a laserului Nd:YAG/Cr4+:YAG,
pentru
emisia in trenuri de pulsuri.
-
Laserul Nd:YAG/Cr4+:YAG
realizat emite trenuri de pana la 10 pulsuri, fiecare puls cu energia
de 2.5 mJ
si durata de 0.9 ns. O a doua configuratie permite emisia de trenuri de
pana la
cinci pulsuri, fiecare puls cu energia de 3.8 mJ.
- A fost
pregatita camera de ardere pentru experimentele de aprindere cu laser.
- Este in curs
de realizare instalatia de reducere a presiunii si de livrare a H2,
care va permite realizarea de experimente de aprindere a amestecurilor H2/aer.
- Au
fost efectuate experimente
de aprindere cu laser a amestecurilor de CH4/aer,
utilizand
aprinderea intr-un punct cu un puls si cu trenuri de cate doua pulsuri
laser,
precum si aprinderea in patru puncte cu unul si cu trenuri de cate doua
pulsuri
laser. Au fost determinate presiunile maxime si timpii de ardere pentru
fiecare
configuratie de aprindere. S-a facut un studiu al influentei geometriei
de
aprinderea asupra limitelor de aprindere.
- S-au pus
bazele unui model teoretic care sa descrie procesul de aprindere cu
trenuri de
pulsuri laser.
2.
ETAPA
II. Ianuarie -
Decembrie 2023
- Au
fost efectuate experimente de aprindere cu laser ale unor amestecuri
combustibile H2/aer, intr-o camera statica cu volum constant,
considerand pentru aprindere un singur punct. In aceste experimente a fost
utilizat un laser Nd:YAG/Cr4+:YAG de tip ”bujie” laser, cu un singur
fascicul, cu energie pe puls de 3.1 mJ si durata de 0.9 ns. Laserul a fost
operat si in regim de trenuri de pulsuri (”pulse-burst mode”), cu pana la cinci
pulsuri in fiecare tren de pulsuri, cu energie totala de 15.5 mJ.
- Primele
experimente au fost realizate la presiune initiala Pin= 1 bar,
utilizand pentru aprindere un singur puls laser. Au fost considerate amestecuri
H2/aer cu un raport de echivalență relativ, l in domeniul 1.5 - 5.0. A fost pus in evidenta
efectul de autoaprindere (pentru lambda =
1.5), precum si cel de aprindere in doua etape, care s-a manifestat pentru un
domeniu lambda= 3.8 - 4.55. In continuare, aprinderea s-a
facut cu trenuri de pana la cinci pulsuri laser. Mentionam ca in timp ce
aprinderile cu doua, trei si patru pulsuri au adus schimbari in curbele de
presiune, acestea nu au fost evidente si pentru aprinderea cu cinci pulsuri laser.
Din acest motiv, aprinderea s-a facut cu patru pulsuri laser insa, periodic,
s-a verificat si ca nu sunt diferente in curbele de presiunea fata de
aprinderea cu trenuri de cate cinci pulsuri laser.
- Din
curbele de presiune, inregistrate pentru fiecare lambda, au fost determinate
presiunile maxime si timpii de combustie; au fost considerati trei timpi de
combustie, conform standard IP 541/06: timpul de intarziere in combustie, tMCD;
timpul principal de combustie, tMCP si timpul de la aprindere pana
la arderea totala, tEC. Analiza acestor date a aratat ca aprinderea
cu trenuri de pulsuri nu influenteaza presiunea maxima pentru amestecuri H2/aer
cu lambda= 1.5 (lambda aproape de raportul stoichiometric). Pentru intervalul lambda= 1.5 -
3.5, au fost observate scaderi in presiune (acestea fiind mici, de cateva
procente) la aprinderea cu trenuri de pulsuri, in comparatie cu aprinderea cu
un singur puls laser. Pentru amestecuri diluate, lambda= 4.0 - 5.0, aprinderea cu
trenuri de pulsuri a dus la cresteri ale presiunii maxime. Pe de alta pare,
aprinderea cu trenuri de pulsuri a condus la accelerarea procesului de
combustie, observandu-se scaderi ale timpilor tMCD si tEC
in comparatie cu aprinderea cu un singur puls laser. Au fost efectuate si
experimente de aprindere cu diferite intervale (de 120 μs, 160 μs, 200 μs si 240 μs) intre pulsurile dintr-un tren de pulsuri.
Prin aceste experimente s-a incercat sa se afle daca este un interval optim
intre pulsuri, informatie de interes pentru modelarile teoretice.
- In
continuare, aprinderea amestecurilor compustibile H2/aer (cu lambda= 2.0 -
5.0) a fost studiata la presiuni ridicate, pana la Pin= 9 bar. Din
curbele de presiune au fost determinate presiunile maxime si timpii de
combustie. Au fost evaluate domeniile de manifestare a aprinderii in doua etape
la diferite presiuni. In plus, au fost determinate limitele de aprindere in
zona cu lambda diluat. S-a constatat ca, in comparatie cu aprinderea cu un singur
puls laser, utilizarea de trenuri de pulsuri asigura aprinderea unor amestecuri
mai diluate pentru presiuni pana la Pin= 1.5 bar. Peste aceasta
presiune aprinderea cu un singur puls laser este de preferat. Spre exemplu, la
Pin= 9 bar, limita de aprindere cu un tren de patru pulsuri laser a
fost lambda= 5.3, aceasta fiind de lambda= 5.9 pentru aprinderea cu un singur puls laser.
- Au
fost facute experimente de aprindere a unor amestecuri combustibile H2/aer
(lambda= 2.0) in mai multe puncte (pana la patru puncte, folosind un laser Nd:YAG/Cr4+:YAG
cu patru fascicule) la presiune initiala Pin= 1 bar, folosind un
singur puls laser. Sunt in curs de desfasurare experimente de aprindere in mai
multe puncte cu trenuri de pulsuri laser.
- Diseminarea
rezultatelor s-a facut prin trimiterea unui manuscris pentru publicare (in revista
indexata ISI), printr-o propunere de brevet la OSIM, prin prezentarea a sase lucrari
la conferinte cu participare internationala (o prezentare de tip keynote, doua
prezentari orale si trei prezentari poster) si prin participarea la un salon de
inventica. Este in pregatire un manuscris, care va fi trimis pentru
posibila publicare intr-o revista indexata ISI.
___________________________________________________________________________________________________________________________________________________________________________
3. ETAPA
III. Ianuarie - Noiembrie
2024
___________________________________________________________________________________________________________________________________________________________________________
ARTICLES
PUBLISHED IN ISI JOURNALS
1. C.
Dumitrache, N. T. Vasile,
G. Croitoru,
2. O.-V.
Grigore and N. Pavel, “Laser ignition of hydrogen/air mixtures in a
constant-volume combustion chamber using a pulse-burst Nd:YAG/Cr4+:YAG
laser spark plug,” Opt. Express 32(17),
30344-30359 (2024). https://doi.org/10.1364/OE.532567
CONFERENCES
1.
N. T. Vasile, G. Croitoru, C. Dumitrache, and
N. Pavel, ”Multi-point, pulse-train laser ignition of methane-air
mixtures by a
high-peak power passively Q-switched Nd:YAG/Cr4+:YAG
compact laser,”
10th
EPS-QEOD EUROPHOTON Conference, 28 Aug. - 2 Sept. 2022, Hannover,
Germany;
presentation TUE-P-1.1. EPJ
Web
Conf. 267, 01002 (2022), https://doi.org/10.1051/epjconf/202226701002
2. C.
Dumitrache, G. Croitoru, N. Pavel, “Laser ignition of CH4-air
mixtures by a four-beam passively Q-switched Nd:YAG/Cr4+:YAG
laser
operating in burst mode," The
9th Tiny Integrated Laser and Laser Ignition
Conference 2023,
19-21 April 2023, Pacifico Yokohama, Yokohama, Japan, presentation
TILA-LIC2-02.
3. O. V. Grigore, A. Craciun, N.
Pavel, “Thermal analysis of a passively Q-switched Nd:YAG/Cr4+:YAG
laser
with multiple-beam output," The
9th Tiny Integrated Laser
and Laser Ignition Conference 2023, 19-21 April 2023,
Pacifico Yokohama, Yokohama, Japan, presentation TILA-LICp-05.
4.
G. Stanciu, F. Voicu, C. A. Brandus, C. E.
Tihon, S. Hau, C. Gheorghe, G. Croitoru, L. Gheorghe, N. Pavel,
”Rare-earths
doped Y2O3 laser
materials,” International Conference on
Crystal Growth and Epitaxy - ICCGE-20, 30 July - 04 August 2023,
Naples, Italy; (poster
presentation PS 2 - P30).
5. O.-V. Grigore, C. Dumitrache, G. Croitoru,
and N. Pavel, “Aspects of CH4-air mixtures laser
ignition by a
multi-point, pulse-train passively Q-switched Nd:YAG/Cr4+:YAG
laser,”
Markus Pessa International Summer School "New Frontiers in Optical
Technologies,"
7 - 11 August 2023, Tampere University, Finland (poster presentation).
6. O.
V. Grigore, N. Pavel, “Single-point, pulse-burst
mode laser-induced ignition of hydrogen-air mixtures in a
constant-volume
combustion chamber by a passively Q-switched Nd:YAG/Cr4+:YAG
laser
spark plug," Tmrees23Gr Technologies and Materials for Renewable
Energy,
Environment and Sustainability, Athens, Greece, November 27-29, 2023
(oral
presentation, online) - Best
Paper Award, European Academy for Sustainable Development.
7. N. Pavel, O.-V. Grigore, G. Stanciu, G. Croitoru,
“Characteristics
of Laser Ignition in Methane/Air and Hydrogen/Air Mixtures in a
Constant-Volume
Combustion Chamber,” 2nd
International Conference Advances in 3OM: Opto-Mechatronics, Opto-Mechanics and
Optical Metrology, 11-14 December 2023, Timisoara, Romania (paper OPT23-13,
keynote presentation). Book of Abstracts, ISSN 2810-5249.
8. O.
V. Grigore, N. Pavel, “Pulse-burst mode laser
ignition of H2/air mixtures by a single-beam passively Q-switched
Nd:YAG/Cr4+:YAG laser,"
The 10th
Tiny Integrated Laser and Laser Ignition Conference 2024, 24-26
April 2024, Pacifico Yokohama, Yokohama, Japan, presentation TILA-LIC3-03 (oral
presentation)
9. G. Stanciu, F. Voicu, C. Tihon, A.M.
Voiculescu, S. Hau, C. Gheorghe, G. Croitoru, L. Gheorghe, and N. Pavel,
”Multilayered Y2O3/RE3+:Y2O3
(RE= Nd, Yb) transparent ceramics: Fabrication process and laser performances,”
The 2nd International Conference on Laser, Plasma and Radiation - Science and
Technology (ICLPR-ST), 16-21 June 2024, Danube Delta, Crişan, Romania (P2-O5,
poster presentation).
10. O. V. Grigore, G. Croitoru, G. Stanciu, A. Craciun,
and N. Pavel, ”Laser ignition of H2/air mixtures by a high-peak
power passively Q-switched Nd:YAG/Cr4+:YAG laser,” The 2nd
International Conference on Laser, Plasma and Radiation - Science and
Technology (ICLPR-ST), 16-21 June 2024, Danube Delta, Crişan, Romania (O5, oral
presentation).
11. O. V. Grigore, G. Croitoru, G. Stanciu, N. Pavel, “Study
of multi-point laser ignition of CH4/air and H2/air mixtures
in a constant-volume combustion chamber," Tmrees24Fr International
Conference on Technologies and Materials for Renewable Energy, Environment and
Sustainability, Metz, France, July 8-10, 2024 (oral presentation, online) - Best
Paper Award, European Academy for Sustainable Development..
PATENT APPLICATIONS
1. N. Pavel, O.-V. Grigore, G. Croitoru, “Sistem Laser pentru Aprinderea Amestecurilor
Combustibile,” cerere brevet de inventie OSIM;
A/00314/21.06.2023.
https://patentimages.storage.googleapis.com/5e/ac/be/457dee77e7d317/RO137724A0.pdf
ALTE REZULTATE
1. Participare la Expozitia Internationala Specializata
“INFOINVENT”, ediţia a XVIII-a, 22-24 noiembrie 2023, Chisinau, Republica
Moldova, cu propunerea de brevet de inventie ” Sistem Laser pentru Aprinderea Amestecurilor Combustibile”. - Medalie
de Bronz; Compartimentul I: Invenţii, soiuri de plante, design industrial.
___________________________________________________________________________________________________________________________________________________________________________
Laboratory of Solid-State Quantum Electronics |