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A P Roskilly - One of the best experts on this subject based on the ideXlab platform.

  • design modelling and validation of a linear joule engine generator designed for renewable energy sources
    Energy Conversion and Management, 2018
    Co-Authors: Boru Jia, Christopher Lawrence, Andrew Smallbone, A P Roskilly
    Abstract:

    Abstract The Linear Joule Engine Generator (LJEG) incorporates the Joule Engine technology and the permanent magnet linear alternator design, which is a promising power generation device for the applications of range extenders for electric vehicles, Combined Heat and Power (CHP) systems, or as a stand-alone power unit. It combines the advantages from both a Joule Engine and a linear alternator, i.e. high efficiency, compact in size, and flexible to renewable energy integration, etc. In this paper, the background and recent developments of the LJEGs are summarised. A detailed 0-dimentional numerical model is described for the evaluation of the system dynamics and thermodynamic characteristics. Model validation is conducted using the test data obtained from both a reciprocating Joule Engine and a LJEG prototype, which proved to be in good agreement with the simulation results. The fundamental operational characteristics of the system were then explained using the validated numerical model. It was found that the Piston Displacement profile has certain similarity with a sinusoidal wave function with an amplitude of 51.0 mm and a frequency of 13 Hz. The electric power output from the linear alternator can reach 4.4 kW e . The engine thermal efficiency can reach above 34%, with an electric generating efficiency of 30%.

  • experimental study of the operation characteristics of an air driven free Piston linear expander
    Applied Energy, 2017
    Co-Authors: Yaodong Wang, Boru Jia, Lin Chen, A P Roskilly
    Abstract:

    Free-Piston engine is a kind of linear internal combustion engine, and shows advantages on simple mechanical structure, low frictional losses, high thermal efficiency and operational flexibility. In this research, an experimental test rig of a dual-Piston air-driven free-Piston linear expander (FPLE) is established using the FPE concept. A linear generator is used to convert the mechanical work of the Pistons into electricity during the expansion process. The Piston dynamics, the output voltage of the generator, and the expander operation frequency, as well as the system energy conversion efficiency are identified. It is observed that the Piston Displacement profile is similar with a sinusoidal wave. The Piston is found to run at relative high speed during the middle stroke, and peak velocity is usually achieved when the Piston approaches the middle stroke. The output voltage of the generator is sensitive with the Piston velocity. With higher driven pressure, the expander frequency is higher. The energy conversion efficiency increases with higher driven pressure and can reach up to 55% with a driven pressure of 3.75bar. This research presents a fundamental analysis of a FPLE prototype, which can be used as a guidance for the future design of this FPLE type.

  • a fast response free Piston engine generator numerical model for control applications
    Applied Energy, 2016
    Co-Authors: Andrew Smallbone, Boru Jia, Huihua Feng, Guohong Tian, Zhengxing Zuo, A P Roskilly
    Abstract:

    Abstract This paper presents a linearization of the dynamic equation for a free-Piston engine generator (FPEG), and simplifies it to a one-degree forced vibration system with viscous damping. The analogy between a mass-spring damper and a FPEG system is expressed, and the solution to the vibration system is solved. The model was successfully validated with respect to experimental data obtained from a prototype. The simulated Piston Displacement during steady operation showed similar trends with the test results and the error of the Displacement amplitude was controlled within 3%. The state-space equations and the transfer function of the system are obtain using the fast response numerical model. An example of model application in the real FEPG control system was provided. Compared to the previous numerical model with differential approaches, the solving time of the proposed fast response model can be significantly reduced. The simplicity and flexibility of the proposed model make it feasible to be implemented to several computing software, i . e . Matlab, AMESim, Labview, Dymola et al. It can be easily implemented to real-time Hardware-in-the-Loop (HIL) simulation model for the future Piston dynamic control system development. In addition, since it reveals how an FPEG operates in a resonant principle, the model is useful for parameter selection in the FPEG design process.

Norman M. Wereley - One of the best experts on this subject based on the ideXlab platform.

  • nondimensional analysis of electrorheological dampers using an eyring constitutive relationship
    Journal of Intelligent Material Systems and Structures, 2005
    Co-Authors: Young-tai Choi, Lionel Bitman, Norman M. Wereley
    Abstract:

    This study presents nondimensional analysis of an Eyring constitutive model to describe the field-dependent behavior of an electrorheological (ER) damper. An ER damper having a damping level comparable to a shock absorber for a small-sized passenger car damper is manufactured, and its performance is modeled using the Eyring model. To accurately identify the rheological parameters of the Eyring model, a parameter identification method is used. The force versus Piston Displacement and velocity behavior of the ER damper are experimentally measured with respect to the applied electric field and excitation frequency. To validate the Eyring model, the experimental results are compared to the predictions of the damping force versus Piston Displacement and velocity behaviors for four different applied fields and excitation frequencies tested. In addition, a set of nondimensional variables to characterize preyield and postyield behaviors of ER or MR fluids are proposed and nondimensional analysis for the Eyring mo...

  • electrorheological damper analysis using an eyring constitutive relationship
    Journal of Intelligent Material Systems and Structures, 2002
    Co-Authors: Lionel Bitman, Young-tai Choi, Norman M. Wereley
    Abstract:

    We validate and assess the applicability of an Eyring constitutive model. The Bingham plastic model has a zero shear rate discontinuity, which leads to inaccuracies in modeling and simulation, and is characterized by two rheological constants for a constant field: yield stress and postyield viscosity. The Eyring model has a smooth transition through the zero shear rate condition, and also has two rheological constants for a constant field. An electrorheological (ER) damper having a damping level comparable to a shock absorber for a small-sized passenger car damper is manufactured, and its performance is predicted using the Eyring model. To accurately identify the rheological parameters of the Eyring model, a parameter identification method was used. The damping force versus Piston Displacement and velocity behaviors of the ER damper are experimentally measured with respect to applied electric field and excitation frequency. To validate the Eyring model, the experimental results are compared with predictions in the damping force versus Piston Displacement and velocity behaviors.

Boru Jia - One of the best experts on this subject based on the ideXlab platform.

  • design modelling and validation of a linear joule engine generator designed for renewable energy sources
    Energy Conversion and Management, 2018
    Co-Authors: Boru Jia, Christopher Lawrence, Andrew Smallbone, A P Roskilly
    Abstract:

    Abstract The Linear Joule Engine Generator (LJEG) incorporates the Joule Engine technology and the permanent magnet linear alternator design, which is a promising power generation device for the applications of range extenders for electric vehicles, Combined Heat and Power (CHP) systems, or as a stand-alone power unit. It combines the advantages from both a Joule Engine and a linear alternator, i.e. high efficiency, compact in size, and flexible to renewable energy integration, etc. In this paper, the background and recent developments of the LJEGs are summarised. A detailed 0-dimentional numerical model is described for the evaluation of the system dynamics and thermodynamic characteristics. Model validation is conducted using the test data obtained from both a reciprocating Joule Engine and a LJEG prototype, which proved to be in good agreement with the simulation results. The fundamental operational characteristics of the system were then explained using the validated numerical model. It was found that the Piston Displacement profile has certain similarity with a sinusoidal wave function with an amplitude of 51.0 mm and a frequency of 13 Hz. The electric power output from the linear alternator can reach 4.4 kW e . The engine thermal efficiency can reach above 34%, with an electric generating efficiency of 30%.

  • experimental study of the operation characteristics of an air driven free Piston linear expander
    Applied Energy, 2017
    Co-Authors: Yaodong Wang, Boru Jia, Lin Chen, A P Roskilly
    Abstract:

    Free-Piston engine is a kind of linear internal combustion engine, and shows advantages on simple mechanical structure, low frictional losses, high thermal efficiency and operational flexibility. In this research, an experimental test rig of a dual-Piston air-driven free-Piston linear expander (FPLE) is established using the FPE concept. A linear generator is used to convert the mechanical work of the Pistons into electricity during the expansion process. The Piston dynamics, the output voltage of the generator, and the expander operation frequency, as well as the system energy conversion efficiency are identified. It is observed that the Piston Displacement profile is similar with a sinusoidal wave. The Piston is found to run at relative high speed during the middle stroke, and peak velocity is usually achieved when the Piston approaches the middle stroke. The output voltage of the generator is sensitive with the Piston velocity. With higher driven pressure, the expander frequency is higher. The energy conversion efficiency increases with higher driven pressure and can reach up to 55% with a driven pressure of 3.75bar. This research presents a fundamental analysis of a FPLE prototype, which can be used as a guidance for the future design of this FPLE type.

  • a fast response free Piston engine generator numerical model for control applications
    Applied Energy, 2016
    Co-Authors: Andrew Smallbone, Boru Jia, Huihua Feng, Guohong Tian, Zhengxing Zuo, A P Roskilly
    Abstract:

    Abstract This paper presents a linearization of the dynamic equation for a free-Piston engine generator (FPEG), and simplifies it to a one-degree forced vibration system with viscous damping. The analogy between a mass-spring damper and a FPEG system is expressed, and the solution to the vibration system is solved. The model was successfully validated with respect to experimental data obtained from a prototype. The simulated Piston Displacement during steady operation showed similar trends with the test results and the error of the Displacement amplitude was controlled within 3%. The state-space equations and the transfer function of the system are obtain using the fast response numerical model. An example of model application in the real FEPG control system was provided. Compared to the previous numerical model with differential approaches, the solving time of the proposed fast response model can be significantly reduced. The simplicity and flexibility of the proposed model make it feasible to be implemented to several computing software, i . e . Matlab, AMESim, Labview, Dymola et al. It can be easily implemented to real-time Hardware-in-the-Loop (HIL) simulation model for the future Piston dynamic control system development. In addition, since it reveals how an FPEG operates in a resonant principle, the model is useful for parameter selection in the FPEG design process.

Tkachenko L. - One of the best experts on this subject based on the ideXlab platform.

  • Dynamics of Tobacco Smoke under Resonant Oscillations in a Closed Tube
    2020
    Co-Authors: Gubaidulli D., Zaripov R., Tkachenko L., Shaidulli L.
    Abstract:

    © 2019, Pleiades Publishing, Ltd. Abstract: The dynamics of tobacco smoke is studied experimentally with nonlinear oscillations in a closed tube. The oscillations of a polydisperse gas suspension at a basic frequency are excited by a flat Piston in the transition regime to shock waves by via a vibration test rig. The effect of the oscillation amplitude and the height of a tube filled with tobacco smoke on the rate of its coagulation and sedimentation is studied. Different cases of smoke-filled tubes are considered: full, three-quarter, half, and quarter fillings. The concentration of tobacco smoke decreases monotonically in time, which is associated with particle coagulation and sedimentation. This process is accelerated by several hundred times as compared with natural sedimentation. The dependence of the coagulation and sedimentation of tobacco smoke on the height of tube filling is nonmonotonic and reaches a minimum with a half-filled tube. The change in the amplitude of Piston Displacement significantly influences the coagulation and sedimentation rate of tobacco smoke only with a full tube. This is associated with the generation of acoustic flows in the form of toroidal vortices in the tube

  • Experimental study of coagulation and sedimentation of gas-particle suspension in closed tube under transfer to the shock-wave regime
    2020
    Co-Authors: Gubaidullin D., Zaripov R., Tkachenko L., Shaidullin L.
    Abstract:

    © 2017, Pleiades Publishing, Ltd. The peculiarities of efficient coagulation and sedimentation of fine-dispersed gas-particle suspension are investigated experimentally at oscillations near the first eigenfrequency in a closed tube at transfer to the shock-wave regime under low excitement amplitudes. We obtain the temporal oscillograms of the gasparticle suspension pressure near the Piston: in the resonance, the oscillograms are close to bursting but retain a continuous mode. The dependences are obtained for coagulation and sedimentation duration on the Piston Displacement amplitude and frequency

  • Nonlinear oscillations of gas in an open tube near the resonance frequency in the shock-free mode
    2020
    Co-Authors: Tkachenko L., Sergienko M.
    Abstract:

    © Published under licence by IOP Publishing Ltd. The forced oscillations of gas in an open tube, excited by harmonical oscillations of Piston in the shock-free mode were investigated near the first first eigenfrequencies. An expression for the pressure oscillations of gas was obtained for the tube with unrounded end without flange. The amplitude impact of Piston Displacement on the oscillations of pressure and velocity of the secondary flow of gas was investigated. The comparison of theoretical calculations with experimental data was executed. The effect of secondary flow on the particle drift along the tube axis with acoustic oscillations of gas was shown

  • Resonant oscillations of a gas in an open tube in the shock-free wave mode
    2020
    Co-Authors: Tkachenko L., Sergienko M.
    Abstract:

    © 2016, Pleiades Publishing, Ltd. Nonlinear gas oscillations excited in an open tube by a flat Piston at one of the tube ends are studied. The sinusoidal Piston oscillations in the shock-free wave mode are created by a vibration exciter near the first eigenfrequency. Expressions for gas pressure oscillations are obtained for a tube with a nonrounded end without a flange and secondary flow velocity components. The influence of the Piston Displacement amplitude on the pressure range and secondary flow velocity of gas is studied. The theoretical calculations of the gas pressure are compared with experimental data. An estimate for the velocity of particle motion along the tube axis is presented with calculated values of the secondary flow velocity

  • Resonance oscillations of an aerosol in a tube with a diaphragm in the shock free-wave mode
    2020
    Co-Authors: Gubaidullin D., Zaripov R., Tkachenko L.
    Abstract:

    © 2014, Pleiades Publishing, Ltd. The results of experimental investigations of nonlinear oscillations of a finely dispersed aerosol in a tube with a diaphragm in the shock free-wave mode in the vicinity of resonance frequencies are presented. The frequency dependences of the peak-to-peak amplitude of aerosol pressure oscillations upon different internal diameters of the diaphragm are found. The time dependences of the numerical concentration of the oscillating aerosol droplets are presented. The effect of the frequency and amplitude of Piston Displacement and the influence of the diaphragm internal diameter on the aerosol clearing time are studied. It is shown that the clearing process of an oscillating aerosol is 5–10 times more efficient than natural deposition of aerosol

Lionel Bitman - One of the best experts on this subject based on the ideXlab platform.

  • nondimensional analysis of electrorheological dampers using an eyring constitutive relationship
    Journal of Intelligent Material Systems and Structures, 2005
    Co-Authors: Young-tai Choi, Lionel Bitman, Norman M. Wereley
    Abstract:

    This study presents nondimensional analysis of an Eyring constitutive model to describe the field-dependent behavior of an electrorheological (ER) damper. An ER damper having a damping level comparable to a shock absorber for a small-sized passenger car damper is manufactured, and its performance is modeled using the Eyring model. To accurately identify the rheological parameters of the Eyring model, a parameter identification method is used. The force versus Piston Displacement and velocity behavior of the ER damper are experimentally measured with respect to the applied electric field and excitation frequency. To validate the Eyring model, the experimental results are compared to the predictions of the damping force versus Piston Displacement and velocity behaviors for four different applied fields and excitation frequencies tested. In addition, a set of nondimensional variables to characterize preyield and postyield behaviors of ER or MR fluids are proposed and nondimensional analysis for the Eyring mo...

  • electrorheological damper analysis using an eyring constitutive relationship
    Journal of Intelligent Material Systems and Structures, 2002
    Co-Authors: Lionel Bitman, Young-tai Choi, Norman M. Wereley
    Abstract:

    We validate and assess the applicability of an Eyring constitutive model. The Bingham plastic model has a zero shear rate discontinuity, which leads to inaccuracies in modeling and simulation, and is characterized by two rheological constants for a constant field: yield stress and postyield viscosity. The Eyring model has a smooth transition through the zero shear rate condition, and also has two rheological constants for a constant field. An electrorheological (ER) damper having a damping level comparable to a shock absorber for a small-sized passenger car damper is manufactured, and its performance is predicted using the Eyring model. To accurately identify the rheological parameters of the Eyring model, a parameter identification method was used. The damping force versus Piston Displacement and velocity behaviors of the ER damper are experimentally measured with respect to applied electric field and excitation frequency. To validate the Eyring model, the experimental results are compared with predictions in the damping force versus Piston Displacement and velocity behaviors.