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This state of art investigation report explains the limitations of Rosin-Rammler approach in comparison with breakup approach. The injection phenomenon of a commercial injector is simulated at various injection pressures, with Heptane (C7H16) in a spray bomb. It is observed that Breakup approach is better suitable in terms of correlation for spray modelling than the Rosin-Rammler approach when the injection pressures are 10 and 20 MPa, the SMD correlation shows also a good correlation at these pressures. At 4 MPa, correlation is a bit poorer, which is coherent as break-up models are best suited to high injection pressures configurations. Also, in each approach the primary dependent parameters are fine-tuned and their effects are discussed.

This paper presents development and verification of an analytical model for a standalone performance study of mini-channel evaporator controlled with thermostatic expansion valve (TXV) for R134a mobile air-conditioning system. The analytical model was developed and validated using MATLAB program. In the existing literatures, studies of analytical evaporator model integrated with TXV for standalone performance was very limited. Effort has been considered to integrate TXV and evaporator model i.e. when there is a change in air flow rate, TXV adjusts refrigerant mass flow rate based on heat load and operating superheat. The developed analytical model emphasize on prediction of refrigerant mass flow rate, heat transfer and refrigerant side pressure drop characteristics. In-tube refrigerant flow was divided into two-phase region and superheated region, considering both dry and wet condition of effectiveness - NTU method.

Electromagnetic brakes are found in a variety of applications. They offer tremendous advantages including: absence of fading, high braking torque and controllability. However they suffer from decreasing torque at low and high speeds. In this study, a novel concept of permanent magnet eddy-current brake is proposed that maintains a flat braking torque profile over a broad speed range. The principle is analytically investigated and numerically validated through finite element simulations using MAXWELL. It is demonstrated that a usably flat braking torque profile can be achieved by altering the path of eddy-currents by magnetic field orientation, thereby affecting the apparent rotor resistance.

This paper is focused on the experimental and numerical investigation of tumble motion on a single cylinder optical engine on three important parameters like engine load conditions, engine speed and level of tumble. Experiments are conducted in an optical engine and the velocity fields are measured with the aid of advanced particle image velocimetry (PIV) measurement technique. For simulation, multiple cases were considered to develop the numerical process for transient in-cylinder aerodynamics to capture the tumble motion and turbulence level in a Spark Ignited (SI) engine. The simulation results, velocity fields of each case were directly compared with the corresponding test results for different crank positions of the engine. On comparison, a good agreement between the measurement and the simulation is obtained for different configurations.

The main objective of this study is to determine the appropriate boundary conditions for the distribution of droplet sizes, speed of the fuel settling at the nozzle of the injector and droplet penetration by numerical simulation using STARCD for a 3-holes injector of ULC-GE. In this study, the Eulerian- Lagrangian approach has been used to model the multiphase domain. A new strategy has been adapted to model droplet initial conditions using the Rosin-Rammler distribution, which is determined by measurement of the Sauter Mean Diameter D₃₂ and the De Brouckere Mean Diameter D₄₃ by the MALVERN method. Further, these droplets undergo the phenomenon of atomization by secondary break-up method and evaporation in the Eulerian domain. The numerical model has been used to evaluate the effects of different initial condition of droplets by changing the discharge coefficient of the nozzle, and the initial droplet size distribution at the nozzle tip.