Unsteady Three-Dimensional Computations of the Penetration Length and Mixing Process of Various Single High-Speed Gas Jets for Engines

Remi Konagaya, Ken Naitoh, Kohta Tsuru, Yasuo Takagi, Yuji Mihara

    Research output: Contribution to journalArticle

    1 Citation (Scopus)

    Abstract

    For various densities of gas jets including very light hydrogen and relatively heavy ones, the penetration length and diffusion process of a single high-speed gas fuel jet injected into air are computed by performing a large eddy simulation (LES) with fewer arbitrary constants applied for the unsteady three-dimensional compressible Navier-Stokes equation. In contrast, traditional ensemble models such as the Reynolds-averaged Navier-Stokes (RANS) equation have several arbitrary constants for fitting purposes. The cubic-interpolated pseudo-particle (CIP) method is employed for discretizing the nonlinear terms. Computations of single-component nitrogen and hydrogen jets were done under initial conditions of a fuel tank pressure of gas fuel = 10 MPa and back pressure of air = 3.5 MPa, i.e., the pressure level inside the combustion chamber after piston compression in the engine. An important point of the present study is to obtain clear evidence for Hamamoto's experimental data that the penetration length of a light hydrogen gas jet of low density is nearly the same as that of relatively heavy gas jets such as nitrogen or carbon dioxide. It is confirmed that the computed penetration lengths of hydrogen and nitrogen gas jets injected into air are nearly the same, although hydrogen has very small inertia due to its low density. It is also stressed that computational results agree fairly well with Hamamoto's empirical data on penetration lengths and diffusion area in the direction normal to the jet axis. Moreover, computations based on the present LES also clarify a physical mechanism underlying combustion instability in engine experiments conducted by Takagi et al., although the RANS is relatively difficult to reveal instability of unsteady flow field.

    Original languageEnglish
    JournalSAE Technical Papers
    Volume2017-March
    Issue numberMarch
    DOIs
    Publication statusPublished - 2017 Mar 28

    Fingerprint

    Engines
    Gases
    Hydrogen
    Gas fuels
    Large eddy simulation
    Nitrogen
    Navier Stokes equations
    Air
    Fuel tanks
    Density of gases
    Unsteady flow
    Combustion chambers
    Pistons
    Flow fields
    Carbon dioxide
    Experiments

    ASJC Scopus subject areas

    • Automotive Engineering
    • Safety, Risk, Reliability and Quality
    • Pollution
    • Industrial and Manufacturing Engineering

    Cite this

    Unsteady Three-Dimensional Computations of the Penetration Length and Mixing Process of Various Single High-Speed Gas Jets for Engines. / Konagaya, Remi; Naitoh, Ken; Tsuru, Kohta; Takagi, Yasuo; Mihara, Yuji.

    In: SAE Technical Papers, Vol. 2017-March, No. March, 28.03.2017.

    Research output: Contribution to journalArticle

    @article{1b4eb2e89040481485205f247755b3c9,
    title = "Unsteady Three-Dimensional Computations of the Penetration Length and Mixing Process of Various Single High-Speed Gas Jets for Engines",
    abstract = "For various densities of gas jets including very light hydrogen and relatively heavy ones, the penetration length and diffusion process of a single high-speed gas fuel jet injected into air are computed by performing a large eddy simulation (LES) with fewer arbitrary constants applied for the unsteady three-dimensional compressible Navier-Stokes equation. In contrast, traditional ensemble models such as the Reynolds-averaged Navier-Stokes (RANS) equation have several arbitrary constants for fitting purposes. The cubic-interpolated pseudo-particle (CIP) method is employed for discretizing the nonlinear terms. Computations of single-component nitrogen and hydrogen jets were done under initial conditions of a fuel tank pressure of gas fuel = 10 MPa and back pressure of air = 3.5 MPa, i.e., the pressure level inside the combustion chamber after piston compression in the engine. An important point of the present study is to obtain clear evidence for Hamamoto's experimental data that the penetration length of a light hydrogen gas jet of low density is nearly the same as that of relatively heavy gas jets such as nitrogen or carbon dioxide. It is confirmed that the computed penetration lengths of hydrogen and nitrogen gas jets injected into air are nearly the same, although hydrogen has very small inertia due to its low density. It is also stressed that computational results agree fairly well with Hamamoto's empirical data on penetration lengths and diffusion area in the direction normal to the jet axis. Moreover, computations based on the present LES also clarify a physical mechanism underlying combustion instability in engine experiments conducted by Takagi et al., although the RANS is relatively difficult to reveal instability of unsteady flow field.",
    author = "Remi Konagaya and Ken Naitoh and Kohta Tsuru and Yasuo Takagi and Yuji Mihara",
    year = "2017",
    month = "3",
    day = "28",
    doi = "10.4271/2017-01-0817",
    language = "English",
    volume = "2017-March",
    journal = "SAE Technical Papers",
    issn = "0148-7191",
    publisher = "SAE International",
    number = "March",

    }

    TY - JOUR

    T1 - Unsteady Three-Dimensional Computations of the Penetration Length and Mixing Process of Various Single High-Speed Gas Jets for Engines

    AU - Konagaya, Remi

    AU - Naitoh, Ken

    AU - Tsuru, Kohta

    AU - Takagi, Yasuo

    AU - Mihara, Yuji

    PY - 2017/3/28

    Y1 - 2017/3/28

    N2 - For various densities of gas jets including very light hydrogen and relatively heavy ones, the penetration length and diffusion process of a single high-speed gas fuel jet injected into air are computed by performing a large eddy simulation (LES) with fewer arbitrary constants applied for the unsteady three-dimensional compressible Navier-Stokes equation. In contrast, traditional ensemble models such as the Reynolds-averaged Navier-Stokes (RANS) equation have several arbitrary constants for fitting purposes. The cubic-interpolated pseudo-particle (CIP) method is employed for discretizing the nonlinear terms. Computations of single-component nitrogen and hydrogen jets were done under initial conditions of a fuel tank pressure of gas fuel = 10 MPa and back pressure of air = 3.5 MPa, i.e., the pressure level inside the combustion chamber after piston compression in the engine. An important point of the present study is to obtain clear evidence for Hamamoto's experimental data that the penetration length of a light hydrogen gas jet of low density is nearly the same as that of relatively heavy gas jets such as nitrogen or carbon dioxide. It is confirmed that the computed penetration lengths of hydrogen and nitrogen gas jets injected into air are nearly the same, although hydrogen has very small inertia due to its low density. It is also stressed that computational results agree fairly well with Hamamoto's empirical data on penetration lengths and diffusion area in the direction normal to the jet axis. Moreover, computations based on the present LES also clarify a physical mechanism underlying combustion instability in engine experiments conducted by Takagi et al., although the RANS is relatively difficult to reveal instability of unsteady flow field.

    AB - For various densities of gas jets including very light hydrogen and relatively heavy ones, the penetration length and diffusion process of a single high-speed gas fuel jet injected into air are computed by performing a large eddy simulation (LES) with fewer arbitrary constants applied for the unsteady three-dimensional compressible Navier-Stokes equation. In contrast, traditional ensemble models such as the Reynolds-averaged Navier-Stokes (RANS) equation have several arbitrary constants for fitting purposes. The cubic-interpolated pseudo-particle (CIP) method is employed for discretizing the nonlinear terms. Computations of single-component nitrogen and hydrogen jets were done under initial conditions of a fuel tank pressure of gas fuel = 10 MPa and back pressure of air = 3.5 MPa, i.e., the pressure level inside the combustion chamber after piston compression in the engine. An important point of the present study is to obtain clear evidence for Hamamoto's experimental data that the penetration length of a light hydrogen gas jet of low density is nearly the same as that of relatively heavy gas jets such as nitrogen or carbon dioxide. It is confirmed that the computed penetration lengths of hydrogen and nitrogen gas jets injected into air are nearly the same, although hydrogen has very small inertia due to its low density. It is also stressed that computational results agree fairly well with Hamamoto's empirical data on penetration lengths and diffusion area in the direction normal to the jet axis. Moreover, computations based on the present LES also clarify a physical mechanism underlying combustion instability in engine experiments conducted by Takagi et al., although the RANS is relatively difficult to reveal instability of unsteady flow field.

    UR - http://www.scopus.com/inward/record.url?scp=85019014302&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=85019014302&partnerID=8YFLogxK

    U2 - 10.4271/2017-01-0817

    DO - 10.4271/2017-01-0817

    M3 - Article

    VL - 2017-March

    JO - SAE Technical Papers

    JF - SAE Technical Papers

    SN - 0148-7191

    IS - March

    ER -