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The present paper shows the main characteristic of a numerical simulation tool, developed in the framework of the European H2020 project MAHEPA, to estimate optimal flight performance of a generic aircraft featuring a Hybrid powertrain. The purpose of the study is to determine optimal flight trajectories together with optimal power controls when a powertrain with multi-energy or multi-power sources (as the case of a generic hybrid one) is considered. For this purpose a complete new software has been developed, which is composed by three main parts: a mission performance “analyser” where the system dynamics of the problem is determined and it solves the aircraft Equation of Motion; a powertrain simulator that determines the operating conditions of the powertrain components and it ultimately computes the consumption of each energy source; a numerical algorithm that optimizes the aircraft control variables to determine both the optimum flight trajectory and the power management according to a certain objective functions and a variety of constraints. Different study cases are discussed when two existing flying hybrid aircraft are considered: a Hybrid-Electric (HE) Pipistrel Panthera aircraft and a Fuel-Cell hybrid (FCH) Pipistrel HY4. Results are presented also depending on the capability to simulate the entire mission as a whole (Single-Phase approach) as well as through the distinction of different flight segments as in the case of the Multi-Phase approach. In addition, two different resolution algorithms are tested in order to evaluate what are the aspects that might dictate the selection of the most suitable one., Flight Performance and Propulsion

Gout is the most prevalent form of inflammatory arthritis, with a strong impact on individual health and healthcare systems. This article reviews clinical and experimental evidences about gout emerged throughout the 2019. Starting with an epidemiological analysis, the review explores new insights on genetic factors influencing the development of gout flare, pathogenetic mechanisms, risk factors for the disease and comorbidities. An overview on pharmacological therapies and recent knowledge on the impact of lifestyle and dietary habits are also included. Finally, the review contains a novel section on animal models, which reflects the renewed interest of researchers in the acute process triggered by monosodium urate crystals.

With the current advances in aircraft design and Lithium-Ion batteries, electric aircraft are expected to serve as a replacement for conventional, short-range aircraft. This paper addresses the main operational challenges for short-range flights operated with electric aircraft: determining the investment needs for a fleet of electric aircraft, and the logistics of charging stations and swap batteries required to support these flights. A mixed-integer linear program with two phases is proposed. In the first phase, a schedule for flight and battery recharge is developed for a fleet of electric aircraft. In the second phase, optimal times for battery charging are determined, together with an optimal sizing of the number of charging stations and swap batteries. We illustrate our model for short-range flights to and from an European airport and for an electric aircraft designed based on the operational characteristics of a conventional, narrow-body aircraft., Aerospace Transport & Operations, Flight Performance and Propulsion

A unified approach to aircraft mission performance assessment is presented in this work. It provides a detailed and flexible formulation to simulate a complete commercial aviation mission. Based on optimal control theory, with consistent injection of rules and procedures typical of aeronautical operations, it relies on generalized mathematical and flight mechanics models, thereby being applicable to aircraft with very distinct configurations. It is employed for an extensive evaluation of the performance of a conventional commercial aircraft, and of an unconventional box-wing aircraft, referred to as the PrandtlPlane. The PrandtlPlane features redundant control surfaces, and it is able to employ Direct Lift Control. To demonstrate the versatility of the performance evaluation approach, the mission-level benefits of using Direct Lift Control as an unconventional control technique are assessed. The PrandtlPlane is seen to be competitive in terms of its fuel consumption per passenger per kilometer. However, this beneficial fuel performance comes at the price of slower flight. The benefits of using Direct Lift are present but marginal, both in terms of fuel consumption and flight time. Nonetheless, enabling Direct Lift Control results in a broader range of viable trajectories, such that the aircraft no longer requires cruise-climb for maximum fuel economy., Flight Performance and Propulsion