Modeled impacts of stratospheric ozone and water vapor perturbations with implications for high-speed civil transport aircraft

1995 ◽  
Vol 100 (D4) ◽  
pp. 7381-7396 ◽  
Author(s):  
David Rind ◽  
Patrick Lonergan
Keyword(s):  
Water Vapor ◽  
High Speed ◽  
Stratospheric Ozone ◽  
Transport Aircraft

Propelling Nozzle Research

1964 ◽  
Vol 68 (647) ◽  
pp. 717-727 ◽  
Author(s):  
W. G. E. Lewis
Keyword(s):  
High Speed ◽  
High Performance ◽  
Research Programme ◽  
Static Tests ◽  
Transport Aircraft ◽  
Supersonic Transport ◽  
Design Behaviour ◽  
Base Bleed ◽  
Critical Phases ◽  
The Ideal

SummaryThe current interest in supersonic transport aircraft makes it appropriate to consider the problems of propulsion nozzle systems for high speed flight. The discussion will be confined mainly to this field of activity.In the absence of external drag and weight factors, the ideal configuration to maintain optimum thrust at all flight speeds would employ a mechanically variable area ratio nozzle. By such means the jet flow could be fully and properly expanded at all times.A practical design to accommodate such variations is inherently complex, and so an alternative solution using aerodynamic techniques has been sought. It is necessary to remember that the success of whatever method is eventually chosen must rest on its ability to combine a high performance at cruise with very small loss during other critical phases of the flight plan.This paper describes some of the results of a nozzle research programme aimed primarily at solving the above problem, with an attempt to explain the philosophy behind the aerodynamic techniques tried. Some discussion is given of the experimental difficulties in establishing a sufficiently accurate standard of measurement for design point performance. In a few chosen configurations experimental results have been extensively backed by theoretical studies.The need to demonstrate off-design behaviour in the presence of an external flow field is stressed, with special reference to the misleading results often obtained from static tests.Finally, some attention is given to the question of base bleed, with its repercussions on the installation of the propulsion nozzle in an aircraft.

scholarly journals Ground-based remote sensing of thin clouds in the Arctic

2012 ◽  
Vol 5 (6) ◽  
pp. 8653-8699 ◽  
Author(s):  
T. J. Garrett ◽  
C. Zhao
Keyword(s):  
Water Vapor ◽  
Thermal Emission ◽  
Stratospheric Ozone ◽  
Microwave Radiometer ◽  
Single Layer ◽  
Primary Source ◽  
The Arctic ◽  
Liquid Water Path ◽  
Water Path ◽  
Microphysical Properties

Abstract. This paper describes a method for using interferometer measurements of downwelling thermal radiation to retrieve the properties of single-layer clouds. Cloud phase is determined from ratios of thermal emission in three "micro-windows" where absorption by water vapor is particularly small. Cloud microphysical and optical properties are retrieved from thermal emission in two micro-windows, constrained by the transmission through clouds of stratospheric ozone emission. Assuming a cloud does not approximate a blackbody, the estimated 95% confidence retrieval errors in effective radius, visible optical depth, number concentration, and water path are, respectively, 10%, 20%, 38% (55% for ice crystals), and 16%. Applied to data from the Atmospheric Radiation Measurement program (ARM) North Slope of Alaska – Adjacent Arctic Ocean (NSA-AAO) site near Barrow, Alaska, retrievals show general agreement with ground-based microwave radiometer measurements of liquid water path. Compared to other retrieval methods, advantages of this technique include its ability to characterize thin clouds year round, that water vapor is not a primary source of retrieval error, and that the retrievals of microphysical properties are only weakly sensitive to retrieved cloud phase. The primary limitation is the inapplicability to thicker clouds that radiate as blackbodies.

Control of Machining Process for Titanium Alloy Based on Green Cooling and Lubricating Technology

2012 ◽  
Vol 580 ◽  
pp. 7-11
Author(s):  
Yue Zhang ◽  
Li Han ◽  
You Jun Zhang ◽  
Xi Chuan Zhang
Keyword(s):  
Titanium Alloy ◽  
Water Vapor ◽  
High Speed ◽  
Cutting Temperature ◽  
Small Diameter ◽  
Machining Process ◽  
Machined Surface ◽  
Cutting Zone ◽  
Cutting Experiments ◽  
Special Control

The machining process of titanium alloys always need special control by using coolant and lubricant as it is one of the difficult-to-cut materials. The cutting experiments are carried out based on green cooling and lubricating technology. To achieve green cutting of titanium alloy Ti-6Al-4V with water vapor cooling and lubricating, a minitype generator is developed. Compared to dry and wet cutting, the using of water vapor decreases the cutting force and the cutting temperature respectively; enhances the machined surface. And it can help to chip forming and breaking. Water vapor application also improves Ti-6Al-4V machinability. The excellent cooling and lubricating action of water vapor could be summarized that water molecule has polarity, small diameter and high speed, can be easily and rapidly to proceed adsorption in the cutting zone. The results indicate that the using of water vapor has the potential to attain the green cutting of titanium alloy.

ACTION OF HIGH SPEED ELECTRONS ON METHANE, OXYGEN AND CARBON MONOXIDE

1930 ◽  
Vol 3 (3) ◽  
pp. 241-251 ◽  
Author(s):  
J. C. McLennan F.R.S. ◽  
J. V. S. Glass B.A.
Keyword(s):  
Carbon Dioxide ◽  
Carbon Monoxide ◽  
Water Vapor ◽  
Formic Acid ◽  
Total Pressure ◽  
High Speed ◽  
Reaction Rate ◽  
First Order ◽  
Gaseous Products ◽  
Retarding Effect

This paper deals with the action of cathode rays on gases and gas mixtures. Methane, methane-oxygen mixtures, carbon monoxide and carbon monoxide-oxygen mixtures were examined. Methane gave small percentages of hydrogen and ethane. Methane and oxygen mixtures gave as gaseous products, carbon monoxide, carbon dioxide and hydrogen, the only other products being water and formic acid. The relative proportions of the products do not vary widely under a wide variation of conditions.The reaction was found to be of the first order with respect to pressure. The reaction rate increases linearly with the voltage up to a certain value, after which it becomes nearly independent of the voltage.The action of cathode rays on carbon monoxide produces carbon dioxide and a solid brown suboxide which is extremely soluble in water, and its composition corresponds to a formula (C3O)n. If the carbon monoxide is moist, no visible amount of solid or liquid is found and there is less carbon dioxide.Carbon monoxide-oxygen mixtures under the action of cathode rays form carbon dioxide. Presence of water vapor has a retarding effect on the reaction. For mixtures of the same composition the reaction rate is proportional to the total pressure. For dry mixtures the product increases with the carbon monoxide present; when moist it is much less, and independent of the carbon monoxide.

Volcanically induced stratospheric water vapor changes

2020 ◽  
Author(s):  
Clarissa Kroll ◽  
Alon Azulay ◽  
Hauke Schmidt ◽  
Claudia Timmreck
Keyword(s):  
Water Vapor ◽  
Stratospheric Ozone ◽  
Statistical Significance ◽  
Volcanic Eruptions ◽  
Internal Variability ◽  
Radiation Budget ◽  
Volcanic Plume ◽  
Indirect Pathway ◽  
Maximum Increase ◽  
Stratospheric Water Vapor

<p><span>Stratospheric water vapor (SWV) is important not only for stratospheric ozone chemistry but also due to its influence on the atmospheric radiation budget.</span></p><p><span>After volcanic eruptions, SWV is known to increase due to two different mechanisms: First, water within the volcanic plume is directly injected into the stratosphere during the eruption itself. Second, the volcanic aerosols lead to a warming of the lower stratosphere including the tropopause layer. The increased temperature of the cold point allows an increased water vapor transit from the troposphere to the stratosphere. Not much is known about this process as it is obscured by internal variability and observations are scare.</span></p><p><span>To better understand the increased SWV entry via the indirect pathway after volcanic eruptions we employ a suite of large volcanically perturbed ensemble simulations of the MPI-ESM1.2-LR for five different eruptions strengths (2.5 Mt, 5 Mt, 10 Mt, 20 Mt and 40 Mt sulfur). Each ensemble consists of 100 realizations for a time period of 3 years.</span></p><p><span>Our work mainly focuses on the tropical tropopause layer (TTL) quantifying changes in relevant parameters such as the atmospheric temperature profile and the consequent increase in SWV. A maximum increase of up to 4 ppmm in the first two years after the eruption is found in the case of the 40 Mt eruption. Furthermore the large ensemble size additionally allows for an analysis of the statistical significance and influence of variability, showing that SWV increases can already be detected for the 2.5 Mt eruption in the ensemble mean, for single ensemble members the internal variability dominates the SWV entry up to an eruption strength of 10 Mt to 20 Mt depending on the season and time after the eruption. The study is complemented by investigations using the 1D radiative convective equilibrium model konrad to understand the radiative effects of the SWV increase.</span></p>

What we do with Human Factors Data and Theory: A Flight Deck Design Philosophy for the High Speed Civil Transport Aircraft

1994 ◽  
Vol 38 (16) ◽  
pp. 1003-1007
Author(s):  
K. Michael Dresel ◽  
David D. T. Pepitone
Keyword(s):  
High Speed ◽  
System Development ◽  
Current System ◽  
Lessons Learned ◽  
Flight Crew ◽  
Transport Aircraft ◽  
Design Philosophy ◽  
Flight Deck Design ◽  
Human Operators ◽  
Flight Deck

This paper reports on the results and lessons learned from constructing a design philosophy for a new aircraft. The High Speed Civil Transport aircraft is the next-generation supersonic transport, planned for initial operating capability in 2005. Current objectives for the aircraft include cruise speeds of Mach 2.4, ability to take off and land in low visibility, and restricted forward vision. These objectives necessitate consideration of major changes in some of the functions currently allocated to the human flight crew. An explicit design philosophy was defined as the first step in ensuring that system development proceeded with clear emphasis on supporting the human operators in accomplishing the goals of transporting their passengers and cargo safely, comfortably, efficiently and on schedule. This paper discusses the development and details of the integrated flight deck design philosophy that will be used to guide the development of a High Speed Civil Transport flight deck. The paper describes • the goals, scope and benefits of the flight deck design philosophy; • the effect on the current system development process; • the method used to produce the design philosophy; • examples of the philosophy and guideline statements, with rationale; • and finally, suggestions for improving the transfer of basic and applied research into the system design process.

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