Study of explosion propagation in Study of explosion propagation in

elongated closed vesselselongated closed vessels

Duration: 01.05.2013 – 31.10.2015

Director of Project:Dr. Codina Movileanu

Mentor of Project:Dr. Domnina Razus

Postdoctoral Research Project PN-II-RU-PD-2012-3-0035Contract No. 17/26.04.2013

Financing: State budgetName of the Programme PN II:

Human Resources

Subprogram:  

Postdoctoral research project

Budget 300000 leiDuration of contract: 30 monthsContracting Authority: Executive Unit for Financing Higher

Education, Research, Development and Innovation

Contractor: “Ilie Murgulescu” Institute of Physical Chemistry 

Project Budget:Project Budget:

Budget chapter Budget chapter (expenses)(expenses)

20132013

(lei)(lei)

20120144

(lei)(lei)

20120155

(lei)(lei)

TotalTotal

(lei)(lei)

SalariesSalaries 63100 54386 27514 145000

InventoryInventory 11543 10392 5374 27309

MobilityMobility 23454.24 23900 0 47354.24

OverheadOverhead 28775.76 25525 26036 80336.76

TotalTotal 126873 114203 58924 300000

Project Summary:Project Summary:The main objective of this project is the experimental investigation of closed-vessel explosive The main objective of this project is the experimental investigation of closed-vessel explosive

combustion of fuel-air mixtures, in deflagration regime, in elongated cylindrical vessels combustion of fuel-air mixtures, in deflagration regime, in elongated cylindrical vessels

(length/diameter > 3) in order to reveal the heat losses during flame propagation and to evaluate (length/diameter > 3) in order to reveal the heat losses during flame propagation and to evaluate

their impact on the flammability parameters. In these vessels, both central and side ignitions will their impact on the flammability parameters. In these vessels, both central and side ignitions will

be performed.be performed.

The study will be realized with ethylene-air mixtures at various initial concentrations and various The study will be realized with ethylene-air mixtures at various initial concentrations and various

initial pressures, at ambient initial temperature. The objectives of the project are: (1) The initial pressures, at ambient initial temperature. The objectives of the project are: (1) The

experimental determination of the maximum explosion pressures and explosion times for experimental determination of the maximum explosion pressures and explosion times for

ethylene-air mixtures at various pethylene-air mixtures at various p00 in elongated cylindrical vessels with various L/D ratios; (2)The in elongated cylindrical vessels with various L/D ratios; (2)The

calculation of adiabatic explosion pressures for fuel-air mixtures within the flammability range at calculation of adiabatic explosion pressures for fuel-air mixtures within the flammability range at

ambient pambient p00, using available computer packages; (3) The calculation of the maximum rates of , using available computer packages; (3) The calculation of the maximum rates of

pressure rise for fuel-air mixtures with various equivalence ratios at various ppressure rise for fuel-air mixtures with various equivalence ratios at various p 00 in elongated in elongated

cylindrical vessels; (4) The experimental determination of the propagation velocity for cylindrical vessels; (4) The experimental determination of the propagation velocity for

deflagrations of ethylene-air mixtures at various initial pressures in elongated cylindrical vessels. deflagrations of ethylene-air mixtures at various initial pressures in elongated cylindrical vessels.

The knowledge of characteristic parameters of these processes allows the assessment of explosion The knowledge of characteristic parameters of these processes allows the assessment of explosion

risks for flammable mixtures in various conditions and the design of equipment and industrial risks for flammable mixtures in various conditions and the design of equipment and industrial

plants where flammable mixtures might be formed. plants where flammable mixtures might be formed.

Project Objectives:Project Objectives:

I. I. Project objectives 2013Project objectives 20131. 1. Experimental measurement of flammability parameters for stoichiometric ethylene-air Experimental measurement of flammability parameters for stoichiometric ethylene-air

mixtures in three asymmetrical closed vessels with central ignition at ambient mixtures in three asymmetrical closed vessels with central ignition at ambient pp00

and and TT00

2. 2. Examination of maximum explosion pressures and of times to reach the maximum Examination of maximum explosion pressures and of times to reach the maximum pressure as a function of asymmetry ratio R=L/Dpressure as a function of asymmetry ratio R=L/D

3. 3. Calculation of the maximum rates of pressure rise and propagation velocities from Calculation of the maximum rates of pressure rise and propagation velocities from pressure-time history and examination of their variation as a function of the pressure-time history and examination of their variation as a function of the asymmetry ratioasymmetry ratio

4. 4. Experimental measurement of flammability parameters for stoichiometric ethylene-Experimental measurement of flammability parameters for stoichiometric ethylene-air mixtures in 3 asymmetrical closed vessels with central ignition at ambient air mixtures in 3 asymmetrical closed vessels with central ignition at ambient TT00

and various initial pressuresand various initial pressures

5. 5. Computation of adiabatic flammability parametersComputation of adiabatic flammability parameters

Estimated results for 2013:

•Flammability parameters for stoichiometric ethylene-air mixtures in three

asymmetrical closed vessels with central ignition at ambient p0 and T0 ;

•Flammability parameters for for stoichiometric ethylene-air mixtures in 3

asymmetrical closed vessels with central ignition at ambient T0 and various initial

pressures .

Figura 3 – Viteze maxime de crestere a presiunii pentru explozia unui amestec stoichiometric etena-aer in doua celule cilindrice cu aprindere centrala (C3 avand L/D = 8.1; C2 avand L/D = 2.5)

0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07-4-3-2-10123456789

10

p / b

ar,

UIP

t / s

0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07

-100

0

100

200

300

400

500

600

700

800

(dp/d

t) / (bar s-1)

Figura 1 – Variatia de presiune (Δp) si semnalul sondei de ionizare (SI) inregistrate la explozia unui amestec stagnant 6.54 vol. % C2H4-aer in celula cilindrica avand raportul L/D = 1.5, la p0 = 1 bar.

0.00 0.01 0.02 0.03 0.04 0.05 0.06

0

2

4

6

8

10

2

1

p /

bar

t / s

Figura 2- Curbe presiune-timp pentru explozia initiata central a unui amestec stoichiometric etena-aer, la p0 = , T0 = 298 K in doua celule de explozie: 1- celula cilindrica C1 (L/D = 1.5); 2 - celula cilindrica C2 (L/D =2.5 )

0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.00

100

200

300

400

500

600

700

celula C4 celula C5

(dp

/dt) m

ax,

ba

r/s

p0, bar

Experimental results:

Project Objectives:Project Objectives:

II. Project objectives 2014II. Project objectives 2014

1.1. Experimental measurement of flammability parameters for ethylene-air Experimental measurement of flammability parameters for ethylene-air

mixtures with various initial concentrations in 3 asymmetrical closed mixtures with various initial concentrations in 3 asymmetrical closed

vessels with central ignition, at ambient pvessels with central ignition, at ambient p00 and T and T00;;

2.2. Experimental measurement of flammability parameters for ethylene-air Experimental measurement of flammability parameters for ethylene-air

mixtures with variable initial concentration in 3 asymmetrical closed mixtures with variable initial concentration in 3 asymmetrical closed

vessels with central ignition at ambient Tvessels with central ignition at ambient T00 and various p and various p00;;

3.3. Management of the project and dissemination of results.Management of the project and dissemination of results.

Estimated results:

Flammability parameters for ethylene-air mixtures with various initial concentrations Flammability parameters for ethylene-air mixtures with various initial concentrations

in three asymetrical closed vessels with central ignition at ambient pin three asymetrical closed vessels with central ignition at ambient p00 and T and T00 (maximum (maximum

explosion pressures and times to reach the maximum explosion pressures, maximum explosion pressures and times to reach the maximum explosion pressures, maximum

rates of pressure rise, propagation velocities);rates of pressure rise, propagation velocities);

Flammability parameters for stoichiometric ethylene-air mixtures in three asymetrical Flammability parameters for stoichiometric ethylene-air mixtures in three asymetrical

closed vessels with central ignition at ambient Tclosed vessels with central ignition at ambient T00 and various initial pressures; and various initial pressures;

Computed adiabatic flammability parameters (adiabatic explosion pressures and Computed adiabatic flammability parameters (adiabatic explosion pressures and

adiabatic flame temperatures)adiabatic flame temperatures)

Heat release profiles in stoichiometric ethylene-air flames at various initial pressures.Heat release profiles in stoichiometric ethylene-air flames at various initial pressures.

Figura 1- Presiuni de explozie masurate in celula cilindrica avand L/D = 8.1 cu aprindere centrala

Figura 2 – Timpii de explozie masurati in celula cilindrica avand L/D = 8.1 cu aprindere centrala

Figura 3 – Viteze maxime de crestere a presiunii pentru explozia unor amestecuri etena-aer in celula cilindrica avand L/D = 8.1 cu aprindere centrala

4 5 6 7 8 9

5

6

7

8

9

10

experimental adiabatic

p max, b

ar

[C2H

4], vol.%

0.0 0.6 1.2 1.810

20

30

40 6 vol. % 5 vol. % 4 vol.%

max

, sp

0, bar

0.0 0.5 1.0 1.50

100

200

300 6 vol. %5 vol. %4 vol. %

(dp/d

t)m

ax,

bar*

s-1

p0, bar

Experimental results:

Dissemination of project results:Dissemination of project results:1. 1. C. Movileanu, D. Razus and V. GosaC. Movileanu, D. Razus and V. Gosa,, Explosion of gaseous ethylene-air mixtures in closed Explosion of gaseous ethylene-air mixtures in closed

cylindrical vessels with asymmetrical ignitioncylindrical vessels with asymmetrical ignition, , International Conference of Physical International Conference of Physical ChemistryChemistry - - ROMPHYSCHEM 15ROMPHYSCHEM 15thth edition: September 11-13, 2013, Bucharest, Romania edition: September 11-13, 2013, Bucharest, Romania (Poster);(Poster);

2. Codina Movileanu , Venera Giurcan, Domnina Razus and Vasile Gosa, Flame propagation in elongated cylindrical vessels with asymmetrical ignition,  Eighth Mediterranean  Eighth Mediterranean Combustion Symposium, September 8-13, 2013 Çesme, İzmir, TurkeyCombustion Symposium, September 8-13, 2013 Çesme, İzmir, Turkey (Poster); (Poster);

3. 3. C. Movileanu, D. Razus, V.C. Movileanu, D. Razus, V. Giurcan and V. GosaGiurcan and V. Gosa, , Explosion parameters of gaseous ethylene-Explosion parameters of gaseous ethylene-air mixtures in elongated cylindrical vesselsair mixtures in elongated cylindrical vessels , PRIOCHEM IX – 24-25 oct. 2013, , PRIOCHEM IX – 24-25 oct. 2013, Bucharest, Romania (Oral communication);Bucharest, Romania (Oral communication);

4. 4. C. Movileanu, D. Razus, V.C. Movileanu, D. Razus, V. Giurcan and V. GosaGiurcan and V. Gosa, , Experimental and numerical study of Experimental and numerical study of ethylene flame propagation in enclosuresethylene flame propagation in enclosures,, French Italian Joint Combustion MeetingFrench Italian Joint Combustion Meeting: : AprilApril 23- 2423- 24, 201, 20144, , PisaPisa, , Italy (Poster);Italy (Poster);

5. 5. C. Movileanu, D. Razus, V.C. Movileanu, D. Razus, V. Giurcan and V. GosaGiurcan and V. Gosa, , Flame propagation of ethylene-air Flame propagation of ethylene-air mixtures in closed tubesmixtures in closed tubes, , 9th International Colloquium on Pulsed and Continuous 9th International Colloquium on Pulsed and Continuous Detonations, 18-24 mai 2014Detonations, 18-24 mai 2014,, Puskin, St. Petersburg, Rusia Puskin, St. Petersburg, Rusia (Oral communication); (Oral communication);

6. 6. C. Movileanu, D. Razus, V.C. Movileanu, D. Razus, V. Giurcan and V. GosaGiurcan and V. Gosa, , Presssure evolution of ethylene-air Presssure evolution of ethylene-air explosion in enclosuresexplosion in enclosures, , XXI Fluid Mechanics ConferenceXXI Fluid Mechanics Conference,, 15-1815-18 iunie iunie 2014 in Cracovia, 2014 in Cracovia, PoloniaPolonia (Poster) (Poster).

7. 7. C. Movileanu, D. Razus, V.C. Movileanu, D. Razus, V. Giurcan and V. GosaGiurcan and V. Gosa, , Study of Burning Velocity of Ethylene-Air Study of Burning Velocity of Ethylene-Air F Flame in Closed Cylindrical Vesselslame in Closed Cylindrical Vessels, , International Conference on Heat Transfer and International Conference on Heat Transfer and Fluid FlowFluid Flow, , Prague, Czech Republic, August 11-12, 2014Prague, Czech Republic, August 11-12, 2014 (Poster). (Poster).

Training of the Project Director:Training of the Project Director:

1. “2013 Princeton Combustion Summer School”, Princeton University, NJ, USA, June 2013.

2. “The Combustion Institute Summer School 2013”, Lund University, Lund Sweden, Aug. 2013.

Published papers:Published papers:

-C. Movileanu, D. Razus, V. Giurcan and V. Gosa, Pressure evolution of ethylene-air explosions in enclosures, J. Physics, Conf. Series, 08/2014, 530(1): 012014.

-C. Movileanu, D. Razus, V. Giurcan and V. Gosa, Flame propagation of ethylene-air mixtures in closed tubes, Proc. Symp. on Pulsed and Continuous Detonations, St. Petersburg, June 2014, pp. 68-72.

-C. Movileanu, D. Razus and V. Gosa, Explosion of gaseous ethylene-air mixtures in closed cylindrical vessels with asymmetrical ignition, submitted to Journal of Hazardous Materials, november 2014.