We employ ratio-based, deterministic, and stochastic frontier approaches to investigate fuel efficiency among 15 large jet operators (mainline airlines) in the U.S. Given the hub-andspoke routing structure and the consequent affiliation between mainline and regional carriers, we consider not only fuel efficiency of individual mainline airlines, but also the joint efficiency of each mainline and...

Nonpremixed jet flames of dimethyl ether (DME) were studied both experimentally and theoretically to investigate flame liftoff near unity Schmidt number. It was found experimentally that although the DME nonpremixed flames have a Schmidt number larger than unity it cannot be lifted directly by increasing the flow rate. Lifted flames can only be established by igniting the mixture in a narrow re...

As a result of jet fuel oxidation, insoluble sediments, called resins or high-temperature deposits, are formed. They significantly reduce the chemmotological reliability aircraft engine system units, i.e., metering equipment, fuel-oil coolers, fine filters, etc. The main factors that intensify oxidation processes quality and meeting specifications as well its temperature. In this regard, aviati...

The application of jet fuel in gas turbines and diesel engines adheres to the Army’s single-fuel forward policy, streamlining supply chains. To ensure precise engine combustion numerical studies, surrogate fuels mechanisms should faithfully replicate real properties traits. In this work, a new four-component containing 39.05% n-dodecane/21.79% isocetane/11.49% decalin/27.67% toluene by mole fra...

A variety of different types of actuators have been previously investigated as flow control devices. Potential applications include the control of boundary layer separation in external flows, as well as jet engine inlet and diffuser flow control. The operating principles for such devices are typically based on either mechanical deflection of control surfaces (which include MEMS flap devices), m...

A novel approach to protecting jet fuel against the effects of water contamination is predicated upon the coupling of the rapid hydrolysis reactions of lipophilic cyclic geminal ethers, with the concomitant production of a hydrophilic acyclic hydroxyester with de-icing properties (Fuel Dehydrating Icing Inhibitors - FDII). To this end, a kinetic appraisal of the hydrolysis reactions of represen...

The problem of breakup of a liquid fuel in a crossflow finds relevance in applications such as lean premixed prevaporized (LPP) ducts, afterburners for gas turbines and combustors for ramjets and scramjets. Combustion efficiency and pollutant formation are directly determined by the efficient mixing of the fuel/air mixture, which is in turn controlled by the breakup of the fuel jet. Liquid jet ...

Methyl-decanoate (MD) is an important surrogate fuel component representing the methyl-ester fraction in biodiesel. In recent years different experimental studies using MD as fuel were reported; detailed as well as reduced mechanisms were developed for both improving our kinetic understanding and engineering applications. Jet stirred reactor (JSR) experiments were performed by Dagaut et al. (20...

We present the development of a new underwater laser cutting process in which a water-jet has been used along with the laser beam to remove the molten material through kerf. The conventional underwater laser cutting usually utilizes a high pressure gas jet along with laser beam to create a dry condition in the cutting zone and also to eject out the molten material. This causes a lot of gas bubb...

Because the amount of fuel usage is huge, and exhaust emissions of commercial transports is regulated under the Kyoto Protocol, how to reduce fuel consumption is an urgent problem for all airlines. The airlines urgently need a practical method to reduce fuel consumptions within constraints to accomplish the mission. The objective for the present paper is to use a model-based method and flight d...