Author: S. L. Manzello
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Abstract : The fuel spray wall interaction phenomenon plays an essential role in determining the emissions and performance of an internal combustion engine. The investigation of single droplet wall interaction is crucial to understanding of a spray wall impingement process. This report is a compilation of the experimental work done to understand the droplet impingement characteristics, through optical diagnostics and temperature measurement. Different fuels and different surface under ambient and elevated temperature conditions are used for these tests, with two objectives: Development of a common depositionsplashing criteria; and Understanding droplet post impingement dynamics variation with factors like: Weber number (ratio of inertia and surface tension forces), and with temperature. The droplet post impinging characteristics include spread factor, height ratio, contact line velocity and dynamic contact angle. The effect of Weber no on droplet impingement characteristics is investigated using water and diesel. The effect of temperature is divided into two subsections: Isothermal (cold wall-cold droplet and hot wall-hot droplet) and non-isothermal conditions (hot wall-cold droplet and hot droplet and cold wall), to understand the influence of both variation in thermophysical properties and heat transfer between droplet and surface. Using the experimental results, a comprehensive review of splashing criteria is done, along with a proposed new correlation for same and concept of splashing probability is introduced. The observation presented for variation in post-impingement characteristics with the mentioned factors are useful for future development of numerical codes.

Author: Jeffrey D. Naber
Publisher:
ISBN:
Category :
Languages : en
Pages : 660

Get Book Here

Book Description

Author: Cong Tran
Publisher:
ISBN:
Category : Collisions (Physics)
Languages : en
Pages : 196

Get Book Here

Book Description
This thesis examines the behavior of water droplets as they impact a heated surface, namely, the droplets' spreading and contracting processes. This data is being used currently in a variety of industrial applications, for example, the automotive industries use this data in the design of fuel injectors in an IC engine. This data is also relevant in the disciplines of nuclear technology, cooling of electronic devices, and steam engines.

Author: S. L. Manzello
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description

Author: Yuntao Pan
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Ice formation and accumulation can lead to operational failure and risks for structures such as power transmission lines, aircrafts, offshore platforms, marine vessels and wind turbines. Liquid repellent surfaces could reduce ice accretion and improve asset integrity and safety in harsh environments. there are significant needs to probe how surface wettability affects the droplet impact, ice formation and ice accretion processes. This study presents experimental results of water droplet impact, droplet dynamics, and icing delay time on flat and inclined stainless-steel surfaces with varying wettabilities. Several different designs of the micro-structure of the hydrophobic surfaces are considered. The commercial hydrophobic coating from Aculon is also used to improve liquid repellency and reduce ice accumulation. It was found that the impact speed and surface wettability are significant factors to the droplet oscillation and the total icing time. The droplet oscillation time is significantly longer on a hydrophobic surface than on a hydrophilic one. Lower surface wettability also significantly increases the droplet total icing time. The droplet total icing time decreases with lower droplet temperature, larger droplet impact velocity, and smaller droplet diameter. The droplet shows a gliding phase on an inclined surface. The total icing time decreases on the inclined surface since the contact area increases due to the gliding process. for typical droplet icing process, the ice formation initiates at the solid-liquid interface and then propagates from bottom to top through the liquid-gas interface. The droplet bounces off from the angled superhydrophobic surface made by electrodeposition at room temperature.

Author: Brett Frederick Bathel
Publisher:
ISBN:
Category : Drops
Languages : en
Pages : 156

Get Book Here

Book Description

Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 6

Get Book Here

Book Description
An experimental study on the interaction of a water mist with a heated surface is described. The long term objective is to produce experimental data that can be used to validate submodels for four key physical phenomena involved in the interaction of sprays with burning surfaces: (1) the effect of buoyancy (caused by the hot combustion products) on the trajectory of a single droplet, (2) the effect of evaporation on the trajectory of a single droplet, (3) the cessation of reaction and reduction in flame spread caused by the droplets on flaming surface combustion, and (4) the reduction in surface temperature caused by the effect of drop impingement, spreading, and evaporation, on surface combustion. The short term objective was to complete experiments that mapped the size history of water droplets as they approached a hot surface using a Malvern Spray Analyzer to study the effect of both buoyance and evaporation on droplet trajectory. Surface temperature profiles were recorded using fine-wire thermocouples. The influence of water mass flow rate and drop size distribution on the hot surface temperature profile is presented and discussed.

Author: S. Chen
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description

Author:
Publisher:
ISBN:
Category : Airplanes
Languages : en
Pages : 404

Get Book Here

Book Description