Using a quasi-static model, it was found that the mass centre of the liquid trajectory is the same as the length-width ratio of the ellipse of the tank. According to the principle of mechanical equivalence, two types of equivalent mechanical models of liquid sloshing in a tank were established, and the relevant parameters of the two models were derived. The simulation results show that the two models can more accurately describe the linear motion of liquid sloshing. The fluid dynamics simulation results of tank liquid vibration frequency division were compared with those obtained using ANSYS Fluent software under similar conditions; it was concluded that the model is more suitable for a liquid vibration frequency range. A simulated test bench was used to verify the two models; the results show the pendulum model is more suitable.

This paper is presented a new alternative technique by combination of state-dependent Riccati equation (SDRE) and sliding mode to overcome the problem of state estimation of chronic myelogenous leukaemia (CML). CML is one of the most common forms of cancer treated with children. The huge number of immune cells impairs the ability of these cells and cause defectiveness of medulla ossium ability to make red blood cells and platelets. Adopting SDRE technique in line with sliding mode observer could help us to achieve an optimum observer gain which prevent and reduce the observer system excitation and makes better estimation in CML dynamical model. SDRE technique brings certain non-linear parts of the system to a seemingly linear structure and avoids linearisation which reduces the accuracy of system. On the other hand, sliding mode applied to estimate disturbances. Combination of these techniques makes a better observer which benefit from both techniques features.

Given that material handling in manufacturing systems is very important, many organisations use automatic guided vehicle (AGV). In recent years, many organisations have intended to have access to an optimal scheduling plan for their manufacturing and transportation system. For this reason, a mathematical model is proposed in this study for scheduling of the production process and AGV's allocation. Production time in any process, setup time, loaded/unloaded trip duration, parking spaces, and the discharge time and loading of products at each workstation are considered in the proposed model. Finally, a numerical example is used to explore the proposed model and it will be solved using GAMS software.

Vehicle transmission system transfers torque and speed from the power source to drive wheels. Continuously variable transmission (CVT) system offers smooth ratio transition where it improves acceleration performance and reduces fuel consumption. Currently, most of the CVT system is actuated by the internal hydraulic circuit where compressibility of oil introduces non-linearity to the system causing difficulty in controlling CVT response. Therefore, a new free-hydraulic CVT system is developed to overcome the shortcomings in existing CVT. The proposed CVT system is designed based on belt-driven type which consists of two sets of variable pulley. Each set of variable pulleys is actuated by an electric motor using slider crank mechanism. The mathematical modelling of CVT mechanism is developed by using Lagrange formulation. The results from this study show that the simulation model of CVT mechanism can produce good performance behaviour in following desired radius position of the real CVT mechanism.

Microgrid system based on multi-machine parallel connection has complex structure and various connection modes. In the process of grid-connected splitting, because of the frequency and voltage deviation between sub-microgrid, it will produce large electric power at the PCC point, which will impact the multi-machine microgrid system and affect the dynamic stability of the system. In order to solve the problem of control accuracy and dynamic stability in this such kind of process, considering the voltage drop and voltage phase angle offset of long-distance lines, an improved droop control method is proposed based on the parallel structure of multiple microgrid, the droop control accuracy is optimised, at the same time the corresponding small signal model is established for parameter optimisation, and the simulation model of improved droop control is established on MATLAB/Simulink. The simulation results verify the rationality and effectiveness of the improved control strategy.

Work presented deals with a new mechanism for particle size-separation based on differential grouping induced by a controlled oscillating flow field. This separation by size may be used for coagulation of like-sized particles. Flow oscillations are induced by a pulsating sphere. The dynamics of particles immersed in such a flow field and their trajectories are analysed mathematically based on perturbation analysis. It is shown that in proximity to the sphere, particle trajectories display strong dependence on particle size (through particle Stokes number), far more so than on initial position. Grouping behaviour is observed under specific operating conditions, and this suggests feasibility of applications in filtration systems, as well as for size-based separation.

Radiation and transpiration are important physical phenomena in greenhouses. In this paper, we present a 3D computational fluid dynamics (CFD) simulation of a system model of a small greenhouse to investigate heat fluxes due to radiation and transpiration. The system model of the greenhouse includes incoming radiation by the sun, radiation heat transfer exchange with the surrounding, convection heat transfer, an active ventilation, open windows, a porous media modelling tomato crop, and a transpiration model coupled to the porous medium of the tomato crop. All simulations were performed transient; modelling the global location of the city of Venlo in the Netherlands with the moving sun. The fine five million cell mesh allowed a high spatial discretisation which, together with a moderate time discretisation, showed details in transpiration and radiation absorption inside the crop as well as details of the humidity distribution inside and around the tomato crop.

Solar drying is used to reduce post-harvest losses. An indirect solar dryer with oriented air is presented. It provides the ability to store energy. This work predicts the outlet temperature at the collector in the single-face and bifacial modes of collector. The heat balance applied to each element is determined taking into account the temporal term which characterises storage in the material. The simulation is done using Matlab software. Both models of the collector are validated by comparing the experimental and theoretical curves. The results show that the two curves of outlet temperatures have the same profile when the global heat transfer coefficient loss is 2.94 W.m−2.K−1, the contact resistance between the absorber and the insulator is 0.025 W−1.m2.K and the velocity is 0.2 m.s−1. The contact resistance has a significant influence on the outlet air temperature but not accessible for controlling temperature compared to the velocity.

International audience

This paper presents our recent progress in the modelling of automotive fuel droplet heating and evaporation processes in conditions close to those in direct-injection internal-combustion engines. Three types of automotive-fuels are considered: biodiesel, diesel and gasoline fuels. Modelling of biodiesel fuel droplets is based on the application of the discrete component (DC) model. A distinctive feature of this model is that it is based on the analytical solutions to the transient heat conduction and species diffusion equations in the liquid phase, taking into account the effects of recirculation. The application of the DC model to fossil fuels (containing potentially hundreds of components), however, is computationally expensive. The modelling of these fuels is based on the recently introduced multi-dimensional quasi-discrete (MDQD) model. This model replaces a large number of components in diesel and gasoline fuels with a much smaller number of quasi-components/components without losing the main features of the original DC model. The MDQD model is shown to accurately predict droplet temperatures and evaporation times and to be much more computationally efficient than the DC model. The main features of these models and their applications to three types of automotive fuel droplets are summarised and discussed.