Authors:Manju Bala First page: 1 Abstract: AbstractStream unsteadiness and fierce change can be all around clarified utilizing another proposed hypothesis - Energy slope hypothesis (Dou, 2005). In this hypothesis, the strength of a stream relies upon the general size of vitality slope in streamwise heading and that transverse way, if there is no work input. In this note, it is indicated dependent on the vitality slope hypothesis that inviscid non-uniform stream is flimsy if the vitality transverse way isn't consistent. This new discovering breaks the old style direct hypothesis from Rayleigh that inviscid stream is precarious if the speed profile has an emphasis point in equal streams and inviscid stream is steady if the speed profile has no enunciation point in equal stream. At that point, security of turning gooey and inviscid streams is examined, and two instances of pivoting streams (pivoting inflexible body movement and free vortex movement) are appeared, separately. Keywords: Energy Gradient; Energy loss; Inviscid Instability; Non-uniform flow, Rotating flow; Viscous Instability. PubDate: 2020-09-17 DOI: 10.37591/.v10i2.982 Issue No:Vol. 10, No. 2 (2020)
Authors:Michael Shoikhedbrod Pages: 15 - 22 Abstract: Precise calculation of the Bond number of a fluid drop and the surface tension coefficient at the fluid-gas interface plays an important role in modeling of the behavior of fluids in aircraft fuel tanks during overloads resulting from flight and the behavior of fluids in power supply and life support systems of spacecraft and space stations. The existing methods of calculation of the Bond number of a fluid drop and of the surface tension coefficient at the fluid-gas interface are based on the method, proposed by F. Bashforth and J. Adams, using tables of calculation of the profiles of dimensionless drops, compiled in accordance with photos of real fluid drops of a wide range of Bond numbers and of contact angles manually. In the existing interpretations of this method, these tables are replaced by computer calculations of the profiles of dimensionless drops. However, due to the fact that these methods simply duplicate these tables, and the choice of the calculated Bond numbers of a fluid drops is performed manually, the precise calculation of the fluid drop profile that corresponds to the actual fluid drop image, and, accordingly, the precise calculation of the surface tension of coefficient at the fluid-gas interface is impossible. The article presents the developed computer program of precise numerical calculation of the Bond numbers of wide range of fluid drops in accordance to photos of real fluid drops, in which adjustment of the Bond number corresponding to a real drops of fluid are carried out automatically by a computer with high accuracy and of precise numerical calculation of surface tension coefficient at the fluid-gas interface, which permits to calculate the precise value of the Bond number of a fluid drop, at which the calculated profiles of a fluid drops coincide with high accuracy with the photographic images of the real profile of a fluid drops and to calculate the precise value of the surface tension coefficient at the fluid-gas interface within a few seconds. Keywords: Bond numbers, Computer numerical calculations, Drop image, Surface tension coefficient at the fluid-gas interface, PubDate: 2020-09-26 DOI: 10.37591/.v10i2.976 Issue No:Vol. 10, No. 2 (2020)
Authors:Sri Sai P. Reddy, Amit Kulkarni Pages: 23 - 32 Abstract: In today’s fast progressing world, there is an advent of technology in all spheres of life. One such area that has grown by leaps and bounds is that of aircraft technology and the systems involved in it. This paper focuses mainly on the technologies/systems used for De-icing and Anti-icing applications in aircrafts (specifically those with fixed wings), be it manned or unmanned (UAVs). Icing and frosting of wings are a common occurrence in aircraft when they reach high altitudes where the vapor condenses and solidifies on the aircraft’s wings/body as ice or frost. This hampers the aerodynamic capabilities of the aircraft and drastically reduces its performance. De-icing and Anti-icing systems are those which curb the formation of such ice and frost on the aircraft body. The systems reviewed in this paper are Mechanical vibration de-icing system, Electromagnetic Expulsion de-icing system (EEDS), Electro-Impulse De-icing system (EIDS), Electro-Expulsive Separation System (EESS), Electro-Mechanical De-icing System, Ultrasonic Deicing System and Shape Memory alloy de-Icing system (SMA). A majority of these systems are fully patented and are already being implemented whereas some of them are in their early stages and are to undergo large scale experimental testing and implementation thereafter. This paper outlines the advancements over the recent years and the working of these systems. PubDate: 2020-10-08 DOI: 10.37591/.v10i2.986 Issue No:Vol. 10, No. 2 (2020)
Authors:Rohit Kumar Pages: 33 - 40 Abstract: Designed to enhance fuel-air mixing at supersonic speeds is one of the most difficult issues in the design of scramjet engine combustors. Various experiments and investigations were considered to boost fuel-air mixture in supersonic air streams. In this analysis, phase effects on transverse gaseous hydrogen injection into supersonic crossflow are examined numerically. Three-dimensional Reynolds Combined Navier-Stokes equations and k- sst turbulence model and perfect gas equation were numerically solved. Current numerical simulation results were compared and checked with available experimental data. Numerical findings from simulations were found in good agreement with experimental values. Then the phase height and phase distance from the injection point was adjusted and the effects on Mach disc height and stagnation pressure loss were evaluated.Keywords: Turboprop, deformation combustion, extended surface, swirling, viscous damping stagnant. PubDate: 2020-09-26 DOI: 10.37591/.v10i2.997 Issue No:Vol. 10, No. 2 (2020)
Authors:Nikhil Advani Pages: 41 - 46 Abstract: The conventional jet engine is optimized to produce high thrust and low specific fuel consumption. The changes are made in compressor which is responsible for the pressure raise in the total process. The compressor section is replaced with two smaller compressors which are parallel to each other with separate individual inlets. It is designed that the two compressors do compression separately and produce high pressure raise. This pressure raise will reduce the fuel demand considerably and increase in thrust.Keywords: High thrust jet engine, low fuel consuming jet engine, double compressor jet engine PubDate: 2020-10-08 DOI: 10.37591/.v10i2.998 Issue No:Vol. 10, No. 2 (2020)
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