In the hollow glass industry, lubricants contribute to the control of heat transfer at the glass/mould interface and consequently to the success of the forming process. The LAMIH of the University of Valenciennes has developed a laboratory test method to determine the evolution of the heat transfer coefficient in different glass/mould contact conditions (pressure, temperature, lubrication, etc). In this paper, the thermal exchanges at the glass I mould interface are analysed with this test method for two lubricants used in the glass industry. Results on the evolution of the heat transfer coefficient for the first seconds of contact are presented and the differences between the temperatures on the glass and the mould surfaces are discussed. The experimental results are then used in the analysis of the first blow in a glass blow-and-blow process. A ZD1/2 finite element model is developed. The identified evolutions of the heat transfer coefficients are introduced into the modelling for the two lubricants via specific interface elements, developed in collaboration with the Faculty of Engineering of Porto. Numerical results are presented for the impact of lubrication on the temperatures of the mould and the glass surfaces during the blowing process.
展开▼
