The Impact of the Physiological Characteristics of Perishables on Aircraft Environmental Control Systems

1968 ◽  
Author(s):  
D. M. Taylor
Keyword(s):  
Control Systems ◽  
Environmental Control ◽  
Physiological Characteristics ◽  
The Impact

Design and Analysis of an Aircraft Thermal Management System Linked to a Low-Bypass Ratio Turbofan Engine

2021 ◽  
Author(s):  
Robert A. Clark ◽  
Mingxuan Shi ◽  
Jonathan Gladin ◽  
Dimitri Mavris
Keyword(s):  
Thermal Management ◽  
Management System ◽  
Environmental Control ◽  
Cooling System ◽  
Heat Transfer Fluid ◽  
Turbofan Engine ◽  
Thermal Management System ◽  
Air Stream ◽  
The Impact ◽  
Bypass Ratio

Abstract The design of an aircraft thermal management system (TMS) that is capable of rejecting heat loads into the bypass stream of a typical low-bypass ratio turbofan engine, or a ram-air stream, is investigated. The TMS consists of an air cycle system (ACS), which is similar to the typical air cycle machines (ACMs) used on current aircraft, both military and commercial. This system turbocharges compressor bleed air and uses heat exchangers in a ram air stream or the engine bypass stream to cool the engine bleed air prior to expanding it to low temperatures suitable for heat rejection. In this study, a simple low-bypass ratio afterburning turbofan engine was modeled in NPSS to provide boundary conditions to the TMS system throughout the flight envelope of a typical military fighter aircraft. The engine was sized to produce sea level static (SLS) thrust roughly equivalent to that of an F-35-class engine. Two different variations of the TMS system, a ram air cooled and a bypass air cooled, were sized to handle a given demanded aircraft heat load, which might include environmental control system (ECS) loads, avionics cooling loads, weapons system loads, or other miscellaneous loads. The architecture and modeling of the TMS is described in detail, and the ability of the sized TMS to reject these demanded aircraft loads throughout several key off-design points was analyzed, along with the impact of ACS engine bleeds on engine thrust and fuel consumption. A comparison is made between the cooling capabilities of the ram-air stream versus the engine bypass stream, along with the benefits and drawbacks of each cooling stream. It is observed that the maximum load dissipation capability of the TMS is tied directly to the amount of engine bleed flow, while the level of bleed flow required is set by the temperature conditions imposed by the aircraft cooling system and the heat transfer fluid used in the ACS thermal transport bus. Furthermore, the higher bypass stream temperatures significantly limit the thermodynamic viability and capability of a TMS designed with bypass air as the ultimate heat sink. The results demonstrate the advantage that adaptive, variable cycle engines (VCEs) may have for future military aircraft designs, as they combine the best features of the two TMS architectures that were studied here.

Smart-device environmental control systems: experiences of people with cervical spinal cord injuries

2017 ◽  
Vol 13 (8) ◽  
pp. 724-730
Author(s):  
Bethany Hooper ◽  
Michele Verdonck ◽  
Delena Amsters ◽  
Michelle Myburg ◽  
Emily Allan
Keyword(s):  
Spinal Cord ◽  
Control Systems ◽  
Spinal Cord Injuries ◽  
Environmental Control ◽  
Cervical Spinal Cord ◽  
Smart Device

scholarly journals The role and tasks of the internal audit and audit committee as bodies supporting effective corporate governance in insurance sector institutions in Poland

2012 ◽  
Vol 3 (4) ◽  
pp. 23-39 ◽  
Author(s):  
Elżbieta Izabela Szczepankiewicz
Keyword(s):  
Control Systems ◽  
Internal Control ◽  
Audit Committee ◽  
Economic Recession ◽  
Internal Audit ◽  
Financial Supervision ◽  
Insurance Sector ◽  
Internal Control System ◽  
The Impact ◽  
Effective Supervision

Faced with the risk of consecutive waves of financial crisis and economic recession, government committees, financial supervision authorities and financial institutions themselves – both in Poland and worldwide – have launched a number of measures to make the supervision of insurance sector institutions more effective, particularly in aspects related to efficient risk management and internal control. The article describes the impact of the amendment of laws and other regulations on the development of the present internal control systems in insurance sector institutions. It draws attention to the need for a new structure of the internal control system, and the role and purpose of the internal audit and the audit committee as the bodies supporting effective supervision in insurance undertakings and reinsurance undertakings.

scholarly journals Q-Learning Neural Controller for Steam Generator Station in Micro Cogeneration Systems

Energies ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 5334
Author(s):  
Krzysztof Lalik ◽  
Mateusz Kozek ◽  
Szymon Podlasek ◽  
Rafał Figaj ◽  
Paweł Gut
Keyword(s):  
Numerical Model ◽  
Control Systems ◽  
Steam Generator ◽  
Full Range ◽  
Combustion Process ◽  
Liquid Fuels ◽  
Control Algorithms ◽  
Exhaust Gas ◽  
Gas Temperature ◽  
The Impact

This article presents the results of the optimization of steam generator control systems powered by mixtures of liquid fuels containing biofuels. The numerical model was based on the results of experimental research of steam generator operation in an open system. The numerical model is used to build control algorithms that improve performance, increase efficiency, reduce fuel consumption and increase safety in the full range of operation of the steam generator and the cogeneration system of which it is a component. In this research, the following parameters were monitored: temperature and pressure of the circulating medium, exhaust gas temperature, oxygen content in exhaust gas, percentage control of oil burner power. Two methods of controlling the steam generator were proposed: the classic one, using the PID regulator, and the advanced one, using artificial neural networks. The work shows how the model is adapted to the real system and the impact of the control algorithms on the efficiency of the combustion process. The example is considered for the implementation of advanced control systems in micro-, small- and medium-power cogeneration and trigeneration systems in order to improve their final efficiency and increase the profitability of implementation.

scholarly journals Fortnightly review: Environmental control systems for people with a disability: an update

BMJ ◽  
1997 ◽  
Vol 315 (7105) ◽  
pp. 409-412 ◽  
Author(s):  
D J Wellings ◽  
J Unsworth
Keyword(s):  
Control Systems ◽  
Environmental Control
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