Dissertation > Excellent graduate degree dissertation topics show

Numerical Simulation of Internal Two-Phase Flow for Effervescent Atomizer and Experimental Study on MQL Machining Performances

Author: WangZhiHao
Tutor: XiaoJiMing
School: Xi'an University of Technology
Course: Mechanical Manufacturing and Automation
Keywords: minimum quantity lubrication effervescent atomization numerical simulation cutting test action mechanism
CLC: TG501.5
Type: Master's thesis
Year: 2010
Downloads: 95
Quote: 0
Read: Download Dissertation

Abstract


In the metal cutting industy, cooling lubricants are one of the most frequently used agents. They help to achieve a prescribed result in terms of cutting temperature,tool life,cutting effect and surface finish. These days, it is required to decrease the consumption of cutting fluid and use chlorine-free cutting fluids for the conservation of the global environment. Disposal cost of the waste cutting oil is increasing. In addition, regulaition for the usage of cutting oils are being enforced. Therefore, from the environmental and economical points of view, green cutting attracts attentions and has been investigated vigorously.In minimum quantity lubrication (MQL) machining, a small amount of biodegradable lubricant is sprayed to the cutting point with compressed air, which provide lubrication and cooling. This paper devise a MQL cutting system which based on the effervescent atomization technology, and simulate the intermal two-phase flow of effervescent atomizer using FLUENT code. Then through the drilling test of 45 steel and ZL107 Al-Si alloy under MQL condition,this paper also study the machining performance of HSS tool.The internal two-phase flow model for effervescent atomizer is constructed based on effervescent atomization principle.Results indicated that there are three regimes of the two-phase flow inside the discharge orifice, one is bubbly fow ,another is annular flow while the other is the intermittent flow. The flow patterns transfered from bubbly flow to intermittent flow and then to annular flow with decreasing of the water flow rate or increasing of the gas to liquid mass ratio (GLR).The cutting performances of the HSS tools for different materials under MQL cutting condition were studied by measuring the tool wear and cutting force directly. Experiment researches for the wear forms,tool lives,cutting forces,etc.on HSS cutting tools during the cutting process,and the comparisons with dry cutting tools were carried out by large numbers of drilling tests for different materials. The variation of the tool wear, cutting forces and built-up edge forming under different machining operations were obtained, and accordingly the applicable scopes and cutting conditions for HSS cutting tools were acquired,which provides an effective way to enlarge the application ranges of HSS tools,reduce tool wear, extend tool life,decrease cutting forces and chip adhesion,improve dimensional precision and machining quality,increase machining efficiency.The MQL flow which is transfered in the form of droplet in air penetrates in the cutting zone directly, and it acts in three different ways, that is, cooling tool and workpiece, lubricating and removing the chips. The efficiency of a MQL flow in relation to a conventional emulsion coolant has been assessed, MQL technique does provide advantages in comparison to conventional wet cutting in terms of lower machining costs and equivalent effects and it is an effective and feasible green cutting technology..

Related Dissertations

  1. The Setting Bases of Working Pressure in LNG Systems and Orthogonal Experiment Design of Heat Exchangers,TQ051.5
  2. Study on Springback of High-Strength Steel Stamping,TG386
  3. Numerical Simulation and Experiment on Hydroforming of Cups with Controllable Radial Pressure,TG386
  4. Research on Technology and Mechanism of Joining Cemented Carbide to Carbon Steel,TG454
  5. Numerical Simulation of Film Cooling in Turbine Cascade with Non-Axisymmetric Endwall Method,V231.3
  6. High Speed Aerodynamic Convection and Coupled Heat Transfer of Complicated Bodies,V215.4
  7. The Analysis on Characteris of Vibration Source about Vertical Vibration of Surrounding Environment Induced by Rail Transit,U211.3
  8. Study on the Heat Transfer Characteristics of Particle Cluster in Circulating Fluidized Bed,TK124
  9. Numerical Simulation of SNCR Process of a 600MW Utility Boiler,TK222
  10. Numerical Simulation of Biomass Direct Reburning,TK16
  11. Numerical Simulation on Pulverized Coal Combustion Process in a 670T/H Tangential Firing Furnace,TK224.11
  12. Numerical Simulation on the Combustion Process in the Furnace of a 1000MW Lignite-Fired USC Boiler,TK224.11
  13. Study on Gas-Solid Two-Phase Flow in Spouted Beds,TK173
  14. Experimental Study and Numerical Simulation on Aerodynamic Field of Tangential Bias Swirl Burner,TK223.23
  15. Characteristic Study of Combustion in Central Reverse Flame Chamber,TK223.21
  16. Numerical Simulation and Contrastive Analysis of Labyrinth Seals and Leaf Seals,TK263.2
  17. Numerical Study on Phosphorus Distribution in Water Environment of the Three Gorges Reservoir,X832
  18. The Design and Performance Simulation of External Valve Small Displacement Pump,TE933.3
  19. Analysis of the Impact of Tailings Dam Stability under Seepage Role,TV649
  20. Study on Hydraulic Fracturing of Low Permeability Reservoir,P618.13
  21. Numerical Simulation and Experimental Study of Air-Assisted Sprayer of Orchard,S491

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metal cutting and machine tools > General issues > Cutting principle and calculation > Coolant
© 2012 www.DissertationTopic.Net  Mobile