Flow in a generic ventral nozzle system was studied experimentally and analytically with a block version of the PARC3D computational fluid dynamics program (a full Navier-Stokes equation solver) in order to evaluate the program's ability to predict system performance and internal flow patterns. For the experimental work a one-thirdsize model tailpipe with a single large rectangular ventral nozz...

Performance and emission characteristics of compression ignition engines depend strongly on inner nozzle flow and spray behavior. These processes control the fuel air mixing, which in turn is critical for the combustion process. The differences in the physical properties of petrodiesel and biodiesel are expected to significantly alter the inner nozzle flow and spray structure and, thus, the per...

The efficiency and emissions of internal combustion (IC) engines are closely tied to the formation of the combustible air-fuel mixture. Direct-injection engines have become more common due to their increased practical flexibility and efficiency, and sprays dominate mixture formation in these engines. Spray formation, or rather the transition from a cylindrical liquid jet to a field of isolated ...

Abstract:-The FSAE guidelines state that it is mandatory for each and every car participating in the said event to have a single circular 20mm restrictor in the intake system. All the air flowing to the engine must pass through this restrictor. Conventionally, a Venturi Nozzle is used as a restrictor. In our research, we have proposed two Nozzles: De-Laval Nozzle and Bell Nozzle as an alternati...

The goal of this research project was to further the development of an electromechanically controlled variable-orifice nozzle by creating an electronic control system and then evaluating that system based on step and ramp inputs. The control system was developed in a programming environment that combined an electronic data acquisition system and actuator with pressure and flow sensors. A propor...

In this study, we numerically examine thrust performance of the linear aerospike nozzle micro-thruster for various nozzle spike lengths and flow parameters in order to identify optimal geometry(s) and operating conditions. Decomposed hydrogen-peroxide is used as the monopropellant in the studies. Performance is characterized for different flow rates (Reynolds numbers) and aerospike lengths, and...

This work consists of studying the effect of needle motion of typical single-hole injectors on spray characteristics. Three-dimensional moving mesh simulations have been carried out to calculate the injection process of cylindrical and conical geometries. The CFD analysis includes a numerical model which simulates the effect of cavitation. Results show that the flow within the nozzle and at the...

The valve mass flux Gv is the calculated value for an ideal (isentropic) nozzle Gn from an appropriate model, multiplied by a discharge coefficient Kd, which accounts for any discrepancies between the (ideal) nozzle model and flow in a real nozzle, as well as any differences between the flow in the nozzle and the actual valve: Gv = Kd Gn (2) As shown in Figure 1, there are obvious similarities ...

The main task of the engine 3D CFD simulation is to support combustion design development. New combustion concepts (e.g. Low Temperature Combustion, HCCI, multiple injection strategies ...) can be analyzed and predicted by detailed thermo-dynamical computation. To achieve this aim many simulation tools are needed: each of them should be capable of reproducing the sensitivities of combustion des...