Optimized Parameter Design Of Double Horizontal Shaft Concrete Forced Mixer

Concrete is an important building material with huge social demands. Engineering nowdays requires better and quicker method of concrete production. The dominant mixer in the market is the double horizontal shaft forced mixer. Because of its complicated structure and numerous parameters that affect the mixing result in a interactional way, the design of double horizontal shaft mixer could be really difficult and depands on experience in most of the situation.The model of this paper is a double horizontal shaft forced mixer from some manufacturer. Paper approaches the question of optimization designing by analyzing the motion and change form of the material particles in the mixer drum during the mixing process, finds the key structural factors which effect the mixing result most. These factors include mixing rotate speed, the installation angle of mixing blade, the arrangement of the mixing arm and the length-width ratio of the mixing drum. Paper gives out a series of recommanded values of these structural factors by the methods of force analysis and equation building. To check the result of these analysis and imitate the interactional affection of all the structural factors, paper build a simulation model of the mixer during working time by the fluid simulation software of Fluent. By comparing the flow field conditions of different factor setting situation, paper finally reach a conclusion of the optimum factor setting.To guarantee the mixing efficiency and avoid segregation in the same time, the optimal mixing rotate speed should be2.4m/s.Through analysis of the material unit mechanical behavior during mixing, it concludes that the probable installation angle should be23°-40°. With the method of simulation model comparing, it comes to a conclution that the optimal installation angle should be40°The wai flow arrangement between the two shafts with a phase angle of60°double-positive-parallel dissuccessive arrangement would be better than other patterns.Building a optimization goal equation of the minimum tube superficial area with the regulation volume, paper obtain the result of optimal length-width ratio which is0.7.The application of CFD fluid simulation software to imitate the concrete mad’s flow field conditions during the mixer working time is more scientific and reliable than the prototype test and other traditional methods. The fluid simulation method is independent of experiment conditions, so it could get a better optimized result with a much lower experiment cost. It offers a new way to the optimized design of concrete mixer researching.