This paper describes the application of the general purpose SINDA/FLUINT thermohydraulic analyzer to the modeling of vapor compression (VC) cycles such as those commonly used in automotive climate control and building HVAC systems. The software is able to simulate transient operation of vapor compression cycles, predicting pressures, coefficients of performance, and condenser/evaporator liquid ...

Over the last 10 years the electrical propulsion fleet grew three times faster than the world fleet. This paper provides an overlook of the main drivers supporting this impressive growth and explores supporting drivers for future growth. The paper also explores two emerging technologies in electrical propulsion and distribution and how these influence ship design: DC distribution and energy sto...

Extensively used in modern gas turbine engines various applications, ranging from aerospace, marine and terrestrial propulsion to power generation pumping, the axial flow turbines have been continuously updated are now capable of high performances reliability. One drawback that has not yet resolved is poor performance at lower- than-nominal regimes. To solve these shortcomings, a new method imp...

Studies of manual wheelchair propulsion often assume bilateral symmetry to simplify data collection, processing, and analysis. However, the validity of this assumption is unclear. Most investigations of wheelchair propulsion symmetry have been limited by a relatively small sample size and a focus on a single propulsion condition (e.g., level propulsion at self-selected speed). The purpose of th...

Objective. To compare the energy expenditure of two types of manual wheelchair propulsion. Design. Experimental and comparative design using matched controls. Background. A new manual wheelchair propulsion technique is proposed to minimize the overload exerted on the upper limb during the classical propulsion. The energy cost and other parameters of this new propulsion technique were evaluated....

Abstract Launcher reusability is the most effective way of reducing access to space costs, but remains a great technical challenge for European aerospace industry. One challenges lies in recovery GNC strategy and algorithms, particular those powered-landing phase, which must enable precise landing with low fuel margins significant dispersions. While state-of-the-art solutions Navigation control...

Abstract In this study, a theoretical and numerical framework for simulating transcritical flows under variety of conditions interest aerospace propulsion applications is presented. A real-fluid multicomponent multiphase thermodynamic model, based on cubic equation state (EoS) vapor–liquid equilibrium (VLE) assumptions, presented to describe mixtures properties. The versatility model reported s...

In recent years, interest in the use of multi-phase (more than three-phase) dc/ac inverters applications such as electric vehicles, traction, more aircraft, ship propulsion, aerospace applications, etc. has been increasing day by day. The paper presents Discontinuous Space Vector Pulse Width Modulation (DSVPWM) technique for control a five-phase two-level inverter. DSVPWM algorithm uses zero, m...

During wheelchair propulsion, in order to apply power to the pushrim effectively, shoulder and trunk stabilization is needed to control arm movements and the consequent transfer of power from the limbs through to the pushrim. Available trunk control may be one of the most important force-generating mechanisms during wheelchair propulsion, particularly when an individual is fatigued or propellin...

Photofission enables a unique capability for the domain of non-chemical space propulsion. An ultra-intense laser enables the capacity to induce nuclear fission through the development of bremsstrahlung photons. A fundamental architecture and performance analysis of a photofission pulsed space propulsion system through the operation of an ultra-intense laser is presented. A historical perspectiv...