Papers by Keyword: Collision Probability

Abstract: The article discusses a technique for assessing the collision probability of particles of dissimilar materials in the process of detonation spraying of composite coatings. In consequence of different properties of initial powder materials (mass, aerodynamic resistance), quality indicators of composite coatings are determined not only with motion parameters of particles but with their mutual position in the flow of detonation products. In the case of using reactive components, interaction of molten particles in the flow can lead to chemical reactions, formation new materials on the substrate, heterogeneous structure of the coating, and deterioration its strength and adhesive properties. Preliminary quantitative assessment of the probability of collision of particles before their contact with the surface of the product affords to make a conclusion about deviation of quantitative indicators of the surface from supposed ones before full-scale tests.

Abstract: A new experimental technique, which is based on a kinetic model of particle transport, has been proposed for determination of the capture efficiency of particles by bubble flotation. Cold model experiments by using an aqueous solution and plastic particles are carried out to validate the new experimental technique. Plastic particles having poor wettability tend to adhere to bubbles and they are removed from an aqueous solution by bubble flotation. On the other hand, plastic particles good in wettability are not captured by bubbles. Capture efficiency can be estimated from a difference of transfer rate between the particles having poor and good wettability. The capture efficiency is found to be proportional to the size ratio of particle and bubble, d_p/d_b, and agrees with theoretical results of Sutherland (1948) for a potential flow condition.

Abstract: In wireless network communication system, the complexity of communication system makes it difficult in experimental teaching and studying transmission interference. As collision probability is an important factor in transmission interference, the model to compute collision probability is very necessary. In this paper, an algorithm is proposed in computing collision probability based on handoff model. Then, a related hardware and software platform is established for analyzing transmission interference in high speed railway system. In simulation, it proves that collision probability can be decreased if the time of sending packet is changed.

Abstract: The AASHTO Correction model is proposed to better adapt the model to the special conditions occurring in Fujian inland waterways. These conditions include ship Type, visibility, and up-down water, navigation systems. The proposed model is related to the probability of ship collision with bridge multi-factor, and further example analysis of this model is also introduced in this paper.

Abstract: Vertical Well-bore Section Anti-collision is one of the main problems to be resolved for clustering directional well during the construction process. In order to effectively reduce the Vertical Well Section collision risk of this wells, the relationship between Wellbore cross-collision probability and the Wellbore separation was studied, the relationship between Wellbore cross-collision probability and the parallel Section length of the two Wellbore was also studied, Based on the above study found the method to calculate the Vertical Wellbore Section cross-collision probability of the clustering directional well. The Vertical Well-bore Section arrangement with smallest cross-collision probability was found by analyzing the cross-collision probability in line style wellhead of cluster wells consisting of 4 wells through this method. The results show that when the Well-bore separation is less than 1.5m. Wellbore collision probability rapidly decrease with the increase of Well-bore separation, the wellbore collision probability trends to smooth when wellbore separation is more than this distance, and the tendency will increase with the increase of parallel section length of the two Wellbore. By optimizing the arrangement and design methods can effectively reduce the collision risk. This study provides a new idea to reduce the overall risk of Cluster Well development.

Abstract: The generation of plasmas and the initiation of electrical breakdown are realized by the phenomenon of electrical discharge which is provoked when we apply a sufficient electric field in a gas. Consequently the free charges are accelerated, new charged particles are created and others are destructed. This can be ranged in four phenomena: elastic collision (recombination), attachment, excitation and ionization. The aim of this paper is to study the basic phenomena in an electrical discharge in the case of Oxygen O₂. Monte Carlo Simulation is used to follow the random trajectory of free charges determining in each path many parameters of the discharge. To determinate electrical and physical parameters, we have used the sampling laws. The spatial distributions of space charges (electrons, positive and negative ions) are also obtained. The determination of electrical field depends on distributions of charged particles obtained by solving the Maxwell equations.