WO2013150393A1 - Chambre de mélange de jets opposés pour le mélange de fluides présentant différents débits massiques - Google Patents

Chambre de mélange de jets opposés pour le mélange de fluides présentant différents débits massiques Download PDF

Info

Publication number
WO2013150393A1
WO2013150393A1 PCT/IB2013/051380 IB2013051380W WO2013150393A1 WO 2013150393 A1 WO2013150393 A1 WO 2013150393A1 IB 2013051380 W IB2013051380 W IB 2013051380W WO 2013150393 A1 WO2013150393 A1 WO 2013150393A1
Authority
WO
WIPO (PCT)
Prior art keywords
mixing chamber
injector
injectors
jets
chamber according
Prior art date
Application number
PCT/IB2013/051380
Other languages
English (en)
Portuguese (pt)
Inventor
José Carlos BRITO LOPES
Ricardo Jorge Nogueira Dos Santos
Madalena Maria Gomes Queiroz Dias
Mohamed Ashar SULTAN MOHAMED YOUSUF
Cláudio António PEREIRA FONTE
Original Assignee
Universidade Do Porto
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Universidade Do Porto filed Critical Universidade Do Porto
Publication of WO2013150393A1 publication Critical patent/WO2013150393A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
    • B29B7/00—Mixing; Kneading
    • B29B7/74—Mixing; Kneading using other mixers or combinations of mixers, e.g. of dissimilar mixers ; Plant
    • B29B7/76—Mixers with stream-impingement mixing head
    • B29B7/7663—Mixers with stream-impingement mixing head the mixing head having an outlet tube with a reciprocating plunger, e.g. with the jets impinging in the tube
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F25/00—Flow mixers; Mixers for falling materials, e.g. solid particles
    • B01F25/20—Jet mixers, i.e. mixers using high-speed fluid streams
    • B01F25/23—Mixing by intersecting jets

Definitions

  • the present invention provides a modified opposed jet mixing method and chamber for ensuring flow regimes within said chambers that enable very short mixing times even at flow regimes characterized by low Reynolds numbers of less than 1000. Said modification relates to varying the injector areas to equalize the power of the jets.
  • This new mixing chamber and method is of particular relevance in RIM - Injection Molding Reaction technology.
  • the mixing chamber is cylindrical or parallelepiped in shape.
  • the mixing chamber has circular injectors with a common axis perpendicular to the axis of said mixing chamber.
  • the mixing chamber has rectangular injectors and their centers are aligned along a common axis that forms a right angle with the axis of said mixing chamber.
  • the mixing chamber exhibits a correction of the power balance of round jets by different jet expansion rates after exiting the injectors with diameter [d and d 2 , separated by
  • Volume and viscosity of the fluid introduced by injector 1 in the form of a medium velocity round jet V 1 , ep 2 and ju 2 are the density and viscosity of the fluid introduced by injector 2 in the form of a medium velocity round jet v 2 .
  • the mixing chamber has coupling means for measuring the static pressure difference in the injector feed lines.
  • the mixing chamber has ellipsoidal injectors having the same diameter perpendicular to the axis of the mixing chamber.
  • the mixing chamber has elongated injectors having the same depth, dimension perpendicular to the axis of the mixing chamber, and the height, injector dimension in the direction of the mixing chamber axis, is changed to match the power of the jets.
  • the mixing chamber has one end closed and the other open.
  • the mixing chamber has two open ends.
  • the mixing chamber has powers equalized by varying the area of the indicators.
  • the mixing chamber wherein the real-time control of the power ratios between the jets is performed by the value of the static pressure difference in the injector supply lines.
  • the mixing chamber has a power ratio of 1.
  • the momentum ratio of jets has been pointed out in the literature (Johnson, 2000 and Santos et al., 2002) as one of the most important operating parameters for mixing in opposite jets, and generally recognized as the parameter that determines the position of the impinging point. of the jets.
  • the momentum ratio of jets in mixers with opposite jets is defined as:
  • d is the diameter of the injector through which the jet is introduced
  • the present invention provides a modified opposed jet mixing method and chamber for ensuring flow regimes within said chambers that enable very short mixing times even at flow regimes characterized by low Reynolds numbers of less than 1000. Said modification relates to varying the injector areas to equalize the power of the jets. This new method and mixing chamber is of particular relevance in RIM - Injection Molding Technology.
  • PR where p is the density of the fluid, V is the average surface velocity of the jet and A is the injector area through which the jet is introduced. Different indices, 1 and 2, are used for the different injectors. For circular injectors the power ratio of the kinetic energy between opposite jets is:
  • d is the diameter of the injector through which the jet is introduced.
  • V is the surface velocity of the jet at the injector outlet
  • d is the injector diameter.
  • the deviation of the impinging point of the opposing jets from the midpoint between the nozzle exits depends on the Reynolds number of jet 1 and jet 2, and the ratio of kinetic energy power between opposite jets, PR, as follows.
  • D is the distance between injectors, or in the case of a cylindrical chamber the diameter of the mixing chamber, and the deviation of the nozzle tipping point from the mixing chamber is normalized by the distance from the injectors or the radius of the mixing chamber of the as follows
  • Figure 6 shows the variation of the dissipation of turbulent energy as a function of ⁇ obtained from the proof-of-concept experiments.
  • Figure 1 Section of a mixing chamber (1) from a RIM machine with two opposite jets entering the chamber through injectors 1 and 2 (2 and 3).
  • the mixing chamber comprises a cleaning piston (5) which at the end of the mold projection is lowered into the chamber. connecting the injectors (2 and 3) with the monomer recirculation circuit lines (4).
  • Figure 2 View of a mixing chamber (1) from a machine
  • Figure 3 Detail of the mixing chamber injectors (2 and 3) of Figure 2.
  • FIG. 4 Parallelepiped mixing chamber (1) with opposite jets.
  • Figure 5 Possible geometries for nozzle exits from opposite jets.
  • Figure 6 Graph of turbulent energy dissipation as a function of the offset of the data point relative to the axis of the mixing chamber.
  • the object of the invention is a method and mixing chamber of opposite jets in which the impinging point equilibrium between them is achieved by equalizing their power by varying the injector area.
  • Opposite jet mixing chambers are static mixers in which generally two fluid jets are introduced into the mixing chamber by two injectors aligned with opposite directions so that the jets collide within a chamber which may have one or more outlets.
  • Mixing chambers may be cylindrical, as in Figure 2, or parallelepiped designated T-jet chambers, as in Figure 4.
  • Injectors are generally circular in cylindrical chambers and have a common axis, generally perpendicular to the axis of the chamber. of mixing.
  • the chambers of T-jets have rectangular injectors that generally extend the entire depth of the chamber and their centers are aligned along a common axis that generally forms a right angle with the axis of the mixing chamber.
  • Other injector geometries may be considered in this invention, namely those shown in Figure 5.
  • Injectors are generally the same, and the use of opposite jet mixers is limited to applications where the mass flow rates of the two fluid streams are approximately equal.
  • To broaden the use of opposite jet mixers it has been proposed to change their areas to equalize jet moments.
  • V is the average surface velocity of the jet
  • A is the injector area through which the jet is introduced.
  • Different indices, 1 and 2 are used for the different injectors. In case both fluids have densities approximately equal the ratio between areas of in is:
  • the ratio between the opposite injector diameters is: where d is the diameter of the injector through which the jet is introduced.
  • the area variation will be made only by varying the height of the injectors, dimension h in Figure 5.
  • the relationship between the heights is:
  • the diameter of the injector 1 is given by
  • D is the diameter of the mixing chamber, or distance between injector outputs 1 and 2 and ⁇ is the viscosity of the fluids.
  • Power balance between the jets can be measured in real time by reading the static pressure difference between the nozzle feed lines.
  • the main advantage of the invention is to allow the operation of opposing jet mixers under high mixing dynamics regimes and with the nozzle tipping point centered on the mixing chamber axis even in cases where fluid streams have different flow rates. Mass.
  • This new mixing chamber and method can eliminate the use of flow restrictors and tuning of the mixer. Mixing conditions are ensured by chamber and injector geometry for each formulation or product and not by trial / error tuning. Failure to use the restrictors also has the advantage of lowering the operating pressure of the machine and the energy consumed for fluid transport.
  • the average fluid velocity in the injector is 190m / s and the Reynolds number for the net polyol current is 150.
  • the power ratio is:
  • This chamber geometry will keep the PR value approximately equal to one for other flow values. provided that the ratio between the mass flow rates is the same and the ratio between the polyol and isocyanate density values remains approximately constant.
  • the same fluids are used in the injector sizing example in a 10mm diameter cylindrical mixing chamber with opposite opposite injectors, applying the formula with the power ratio correction due to different jet opening rates at different Reynolds numbers.
  • the jets impinge on the axis of the mixing chamber.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Injection Moulding Of Plastics Or The Like (AREA)

Abstract

La présente invention concerne une chambre de mélange de jets opposés (1) modifiés pour garantir des régimes d'écoulement à l'intérieur desdites chambres, permettant d'obtenir des temps de mélange très courts, y compris dans des régimes d'écoulement caractérisés par de faibles nombres de Reynolds, inférieurs à 1000. La chambre de mélange comprend un piston de nettoyage (5) qui, à la fin de l'injection du moule, est descendu sur la chambre de manière à relier les injecteurs (2 et 3) aux conduits du circuit de recirculation de monomères (4). Ladite modification est liée à la variation des zones des injecteurs (2 et 3) pour égaliser les puissances des jets. Cette chambre de mélange trouve une application particulière dans la technologie RIM - moulage par injection-réaction.
PCT/IB2013/051380 2012-02-20 2013-02-20 Chambre de mélange de jets opposés pour le mélange de fluides présentant différents débits massiques WO2013150393A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
PT106166A PT106166A (pt) 2012-02-20 2012-02-20 Câmara de mistura de jatos opostos para mistura de fluidos com diferentes débitos mássicos
PT106166 2012-02-20

Publications (1)

Publication Number Publication Date
WO2013150393A1 true WO2013150393A1 (fr) 2013-10-10

Family

ID=48093038

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2013/051380 WO2013150393A1 (fr) 2012-02-20 2013-02-20 Chambre de mélange de jets opposés pour le mélange de fluides présentant différents débits massiques

Country Status (2)

Country Link
PT (1) PT106166A (fr)
WO (1) WO2013150393A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2597422A (en) * 1948-09-11 1952-05-20 Little Inc A Process of forming dispersions
US3706515A (en) 1970-02-20 1972-12-19 Krauss Maffei Ag Device for feeding flowable material to a mold cavity
US4473531A (en) 1981-04-28 1984-09-25 Regents Of The University Of Minnesota Rim mixhead with high pressure recycle
WO2005097477A1 (fr) * 2004-04-05 2005-10-20 Faculdade De Engenharia Da Universidade Do Porto Procede de production de matieres plastiques par moulage par injection et reaction, et dispositif a tete de melange correspondant

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1139885B (it) * 1981-12-01 1986-09-24 Impianti Oms Spa Testa di iniezione ad alta pressione particolarmente per materie plastiche

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2597422A (en) * 1948-09-11 1952-05-20 Little Inc A Process of forming dispersions
US3706515A (en) 1970-02-20 1972-12-19 Krauss Maffei Ag Device for feeding flowable material to a mold cavity
US4473531A (en) 1981-04-28 1984-09-25 Regents Of The University Of Minnesota Rim mixhead with high pressure recycle
WO2005097477A1 (fr) * 2004-04-05 2005-10-20 Faculdade De Engenharia Da Universidade Do Porto Procede de production de matieres plastiques par moulage par injection et reaction, et dispositif a tete de melange correspondant

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
JOHNSON, D. A.: "Experimental and Numerical Examination of Confined Laminar Opposed Jets. Part II Momentum Balancing.", INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER, vol. 27, no. 4, 2000, pages 455 - 463
SANTOS, R.J.; TEIXEIRA, A.M.; COSTA, M.R.P.F.N.; LOPES, J.C.B: "Operational and Design Study of RIM Machines", INTERNATIONAL POLYMER PROCESSING, vol. 17, no. 4, 2002, pages 387 - 394

Also Published As

Publication number Publication date
PT106166A (pt) 2013-08-20

Similar Documents

Publication Publication Date Title
RU2007137436A (ru) Твердые частицы, способ и устройство для их изготовления
BR112013032863B1 (pt) Sistema de distribuição de fase múltipla, trocador de calor submarino e um método de controle de temperatura para hidrocarbonetos
US10722860B2 (en) Mixing reactor and related process
CN103372326A (zh) 用于海上气/液接触塔的分区分配器塔盘
Ghorbani et al. Facile hydrodynamic cavitation ON CHIP via cellulose nanofibers stabilized perfluorodroplets inside layer-by-layer assembled SLIPS surfaces
JP6354341B2 (ja) 溶融金属への旋回流付与方法
CN103372366A (zh) 用于海上气/液接触塔的分配器塔盘
WO2013150393A1 (fr) Chambre de mélange de jets opposés pour le mélange de fluides présentant différents débits massiques
Johnson Experimental and numerical examination of confined laminar opposed jets part I. Momentum imbalance
JP2013230481A5 (fr)
Lysenko et al. Stability of supersonic boundary layer under the influence of heavy gas injection: experimental study
JP2010051959A (ja) 流体流れを分割するための方法
KR20160079428A (ko) 다수 유체 미립자 분무용 노즐 어셈블리
ITMI20081063A1 (it) Gruppo e metodo di trattamento di una sostanza a comportamento liquido, in particolare vino, stoccata in un serbatoio
JP4722840B2 (ja) ２相ストリームを所望の気体／液体比を有する２つ以上のストリームに分割するためのデバイス
McClintic et al. Near-hole thermal field measurements for round compound angle film cooling holes fed by cross-flow
JP2017051998A (ja) 金属の連続鋳造装置、及び、金属の連続鋳造方法
CN206369373U (zh) 制冷系统及其分液器
JP6303796B2 (ja) 貯留槽内低温液体の混合方法及び装置
CN105170069A (zh) 一种塔式气液接触设备均匀布气装置及其用途
JPH0664691A (ja) 流体の分配方法及び流体分配器
CN207680387U (zh) 一种利于多组分气体充分混合的装置
CN206483446U (zh) 一种卧式流化床用多孔板
Kebriaee et al. Experimental Study of Primary Atomization in Triple Co-Planar and Non-Planar Impinging Jets
CN204034676U (zh) 双鱼形反应器

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13716053

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 13716053

Country of ref document: EP

Kind code of ref document: A1