Design of a blow off valve for turbocharged engine applications

On a turbo engine, the Blow of Valve (BOV) is used to relieve the pressure from the turbo output when the throttle is closed. Without the BO y, when the throttle is closed the turbo is suddenly trying to pump air against a closed throttle plate. This creates pressure spike in the turbo output hose and will send back the pressure to the turbine and can damage the turbo engine. When the throttle is opened again, the turbo has to spin up again, creating turbo lag. So, the present of the BOY will opened when the throttle is closed and pressurized the pressure spike to the air to avoid those phenomena. So, good flow of the air inside the BOV is important, the air will smoothly pressurized to the atmosphere if there is no back pressure inside the system. Computer aided design (CAD) and computational fluid dynamic (CFD) software were used as a tool for the design. This design is the improvement of the aftermarket design. The piston surface, size of vent, inlet ports, outlet ports, and also spring plays the role in the BOy. The design analyzed using CFD so can see the flow trajectories of the air inside the BOy

Preliminary Sub-Systems Design Integrated in a Multidisciplinary Design Optimization Framework

The aircraft design is a complex subject since several and completely different design disciplines are involved in the project. Many efforts are made to harmonize and optimize the design trying to combine all disciplines together at the same level of detail. Within the ongoing AGILE (Horizon 2020) research, an aircraft MDO (Multidisciplinary Design Optimization) process is setting up connecting several design tools and competences together. Each tool covers a different design discipline such as aerodynamics, structure, propulsion and systems. This paper focuses on the integration of the sub-system design discipline with the others in order to obtain a complete and optimized aircraft preliminary design. All design parameters used to integrate the sub-system branch with the others are discussed as for their redefinition within the different detail level of the design

Development and Validation of on-board systems control laws

Purpose - The purpose of this paper is to describe the tool and procedure developed in order to design the control laws of several UAV (Unmanned Aerial Vehicle) sub-systems. The authors designed and developed the logics governing: landing gear, nose wheel steering, wheel braking, and fuel system. Design/methodology/approach - This procedure is based on a general purpose, object-oriented, simulation tool. The development method used is based on three-steps. The main structure of the control laws is defined through flow charts; then the logics are ported to ANSI-C programming language; finally the code is implemented inside the status model. The status model is a Matlab-Simulink model, which uses an embedded Matlab-function to model the FCC (Flight Control Computer). The core block is linked with the components, but cannot access their internal model. Interfaces between FCCs and system components in the model reflect real system ones. Findings - The user verifies systems' reactions in real time, through the status model. Using block-oriented approach, development of the control laws and integration of several systems is faster. Practical implications - The tool aims to test and validate the control laws dynamically, helping specialists to find out odd logics or undesired responses, during the pre-design. Originality/value - The development team can test and verify the control laws in various failure scenarios. This tool allows more reliable and effective logics to be produced, which can be directly used on the system

Integration of on-board systems preliminary design discipline within a collaborative 3rd generation MDO framework

The integration of the on-board systems design discipline in a collaborative Multidisciplinary Design and Optimization (MDO) framework is presented in this paper. The collaborative MDO framework developed within the context of the EU funded H2020 AGILE project is selected as reference. The technologies developed or made available in the context of the AGILE project are employed for the integration within the MDO framework of ASTRID, an on-board systems design tool owned by Politecnico di Torino. The connection of the tool with a common namespace (i.e. CPACS) and its implementation within two Process Integration and Design Optimization (PIDO) environments are described. An application study is eventually presented, showing the benefits and the potentialities of the integration of the on-board systems design discipline within a collaborative MDO framework

Hypothesis for Hypersonic Flight development

The aim of this work is to promote the hypersonic flight in order to improve both the affordability of the access to space and the terrestrial flight transportation increasing flight range and reducing flight time. A strategic air vehicle is envisaged partially employing state-of-the-art technologies focusing on configuration and feasibility studies. The purpose is obviously to indicate the technologies on which concentrating the design efforts. To enable the development of future spacecraft, it is believed that the effort have to focused on the development, at low cost, of new technology demonstrator aircraft based on suborbital “tourism spacecraft” and fighter aircraft. An important goal would be the development of small and affordable aircraft able to perform the hypersonic cruise

Effect of the application of an electric field on the performance of a two-phase loop device: Preliminary results

In the last decade, the continuous development of electronics has pointed out the need for a change in mind with regard to thermal management. In the present scenario, Pulsating Heat Pipes (PHPs) are novel promising two-phase passive heat transport devices that seem to meet all present and future thermal requirements. Nevertheless, PHPs governing phenomena are quite unique and not completely understood. In particular, single closed loop PHPs manifest several drawbacks, mostly related to the reduction of device thermal performance and reliability, i.e. the occurrence of multiple operational quasi-steady states. The present research work proposes the application of an electric field as a technique to promote the circulation of the working fluid in a preferential direction and stabilize the device operation. The tested single closed loop PHP is made of a copper tube with an inner tube diameter equal to 2.00 mm and filled with pure ethanol (60% filling ratio). The electric field is generated by a couple of wire-shaped electrodes powered with DC voltage up to 20 kV and laid parallel to the longitudinal axis of the glass tube constituting the adiabatic section. Although the electric field intensity in the working fluid region is weakened both by the polarization phenomenon of the working fluid and by the interposition of the glass tube, the experimental results highlight the influence of the electric field on the device thermal performance and encourage the continuation of the research in this direction

A Modular Rack for Shared Thermo-Fluid Dynamics Experiments in Reduced Gravity Environment

Abstract Parabolic flights represent an important tool for short space-related experiments under reduced gravity conditions. During the ballistic flight manoeuvres, the investigators have the possibility to operate their experiments, in a laboratory-like environment, where the level of gravity subjected to the experiments repetitively in a series of periods of reduced gravity, preceded and followed by periods of hypergravity. Aboard large aircraft, the duration of this phases varies from approximately 20 s for a 0g flight up to up to 32 s for a Martian g level. A parabolic flight rack able to host experiments concerning thermo-fluid dynamics, has been designed, realized and qualified during the ESA 66th Parabolic Flight Campaign. This microgravity research platform, is the first UK facility available for such investigations, providing a data acquisition system, cooling system and heating system compliant with Novespace requirements

SINGLE LOOP PULSATING HEAT PIPE WITH NON-UNIFORM HEATING PATTERNS: FLUID INFRARED VISUALIZATION AND PRESSURE MEASUREMENTS

Abstract. A novel Single Loop Pulsating Heat Pipe (SLPHP) filled at 60% filling ratio with pure ethanol, with an inner diameter of 2mm is tested in Bottom Heated mode varying the heating power. The system is designed with two sapphire tubes mounted between the evaporator and the condenser allowing simultaneous fluid flow high-speed visualizations and IR analysis. Furthermore, two highly accurate pressure transducers carry out local pressure measurements just at the ends of one of the sapphire inserts. Additionally, three heating elements are controlled independently, in such a way to heat up the device varying the distribution of the heating location at the evaporator. It is found that peculiar heating distributions promote the slug/plug flow motion in a preferential direction, increasing the overall performance of the device. Pressure measurements point out that the flow patterns are strictly related to the pressure drop between the evaporator and the condenser. Furthermore, the IR visualization highlights interesting phenomena related to the liquid film dynamics during the device operations, which represent a very useful information for future numerical modeling of Pulsating Heat Pipes