The Interaction Between Shock Waves and Foam in a Shock Tube

An experimental study and a numerical simulation were conducted to investigate the mechanical and thermodynamic processes involved in the interaction between shock waves and low density foam. The experiment was done in a stainless shock tube (80mm in inner diameter, 10mm in wall thickness and 5360mm in length). The velocities of the incident and reflected compression waves in the foam were measured by using piezo-ceramic pressure sensors. The end-wall peak pressure behind the reflected wave in the foam was measured by using a crystal piezoelectric sensor. It is suggested that the high end-wall pressure may be caused by a rapid contact between the foam and the end-wall surface. Both open-cell and closed-cell foams with different length and density were tested. Through comparing the numerical and experimental end-wall pressure, the permeability coefficients a and 0 are quantitatively determined.

CFD analysis of pneumatic conveying in a double-tube-socket (DTS (R)) pipe

A pipeline with a bypass is widely used for the pneumatic conveying of material. The double-tube-socket (DTS (R)) technology, which uses a special inner bypass, represents the current state of the art. Here, a new methodology is proposed based on the use of computational fluid dynamics (CFD) to predict the energy consumption of DTS conveying. The predicted results are in good agreement with those from pilot-scale experiments. (C) 2010 Elsevier Inc. All rights reserved.

Modelling and Instrumentation of Stretch Blow Moulding

The injection stretch blow moulding process is used to manufacture PET containers used in the soft drinks and carbonated soft drinks industry. The process consists of a test tube like specimen known as a preform which is heated, stretch and blown into a mould to form the container. This research is focused on developing a validated simulation of the process thus enabling manufacturers to design their products in a virtual environment without the need to waste time, material and energy. The simulation has been developed using the commercial FEA package Abaqus and has been validated using state of the art data acquisition system consisting of measurements for preform temperature (inner and outer wall) using a device known as THERMOscan (Figure 1), stretch rod force and velocity, internal pressure and air temperature inside the preform using an instrumented stretch rod and the?exact?timing of when the preform touches the mould wall using contact sensors.? In addition, validation studies have also been performed by blowing a perform without a mould and using high sped imaging technology in cooperation with an advanced digital image correlation system (VIC 3D) to provided new quantitative information on the behaviour of PET during blowing.? The approach has resulted in a realistic simulation in terms of accurate input parameters, preform shape evolution and prediction of final properties.

Photocatalytic organic synthesis in an NMR tube:CC coupling of phenoxyacetic acid and acrylamide

NMR was used to study the semiconductor photocatalytic (SPC) CC coupling of phenoxyacetic acid (PAA) with acrylamide (ACM) in an NMR tube photoreactor. Using an NMR tube with a sol-gel titania inner coating as a photoreactor, this reaction is relatively clean, forming only 1 product, 4-phenoxybutanamide (4-PB), in yields up to 78%. This SPC reaction is used to assess the activity of the sol-gel titania coating as a function of their annealing temperature, which alters the surface area and phase of the titania, and the general reusability of the TiO coated NMR tubes. The optimum temperature range for annealing the sol-gel titania films is between 450 °C and 800 °C, with the maximum yield and rate attained at 450 °C. Despite a decrease in the initial rates of formation of 4-PB above an annealing temperature of 450 °C, the final product yields remained similar, giving maximum yields within 60 min of irradiation. The reusability study reveals that the activity of the sol-gel titania can quickly deteriorate with repeated use due to the adsorption of yellow/brown coloured, insoluble, most likely organic polymeric, material and its screening effect on the underlying photocatalyst. The titania can, however, be restored to its original activity by a simple heat treatment at 450 °C for 30 min.

The challenge for the dairy industry arising from the new health claims standard: an impetus for innovation

The publication of a Preliminary Final Assessment Report on 4 April 2007 heralded another step towards the introduction of a new Health Claims Standard to be inserted into the Australia New Zealand Food Standards Code. This Health Claims Standard, once approved by the Board of Food Standards Australia New Zealand and by the Australia New Zealand Food Regulation Ministerial Council, will permit the making of certain substantiated health claims. Prior to the introduction of the new Standard, health claims have not been permitted on food labels, with the exception of claims in relation to maternal folate consumption and its positive effect in reducing the risk of foetal neural tube defects. The new Health Claims Standard as outlined in the Preliminary Final Assessment Report is likely to have a significant impact on the dairy industry. This paper seeks to analyse that impact, including threats, opportunities and challenges that the Standard poses to the dairy industry and other food suppliers.

Numerical investigation of ramp and constant pressurization system during tube crushing process

The requirement for the automotive industry at present and even more so in the future is to simultaneously develop materials, economic forming processes and techniques for weight reduction of the component. To fulfil this need steel manufacturers have developed Advanced High Strength Steels which have high strength and good formability. Due to high strength, material thickness can be reduced without compromising the function of the component. High pressure hydro forming is one process that can be used to produce complex components from these materials. However, reduction in material thickness of these steels does not result in a large decrease of internal fluid pressure and die closing force during tube hydro forming and hence the higher strengths of these steels will require higher pressures. Tube crushing is a process in which the component can be formed with low pressures. In this paper numerical comparison of ramp and constant pressurization system during tube crushing for a TRIP steel is studied. It is proposed that ramp pressure is the best option to obtain a part with accurate geometrical shape from tube crushing with less die closing force. The stress and thickness distribution of the part during tube crushing were critically analysed.

An investigation of complex shapes during low pressure tube hydroforming

Hollow structures made of Advanced High Strength Steel (AHSS) are increasingly used in the automobile industry for crash and structural components. Generally high pressure hydroforming is used to form these tabular parts, which is a costly manufacturing process due to the high pressure equipment and large tonnage presses required. A new process termed low pressure hydroforming, where a pressurized tube is crushed between two dies, represents a more cost effective alternative due to the lower pressures and die closing forces required.

In this study the low pressure tube hydroforming of one simple and two different complex hollow shapes is investigated. The complexities of the pat1S compared to simple shapes are critically studied and the die filling conditions are investigated and discussed. FUl1hennore the thickness distributions over the circumference of the part during forming are analyzed.

Experimental investigation of gravitational gas separation in an inclined annular channel

The oil industry uses gas separators in production wells as the free gas present in the suction of the pump reduces the pumping efficiency and pump lifetime. Therefore, free gas is one of the most important variables in the design of pumping systems. However, in the literature there is little information on these separators. It is the case of the inverted-shroud gravitational gas separator. It has an annular geometry due to the installation of a cylindrical container in between the well casing and pioduction pipe (tubing). The purpose of the present study is to understand the phenomenology and behavior of inverted-shroud separator. Experimental tests were performed in a 10.5-m-length inclinable glass tube with air and water as working fluids. The water flow rate was in the range of 8.265-26.117 l/min and the average inlet air mass flow rate was 1.1041 kg/h, with inclination angles of 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, 80 degrees and 85 degrees. One of the findings is that the length between the inner annular level and production pipe inlet is one of the most important design parameters and based on that a new criterion for total gas separation is proposed. We also found that the phenomenology of the studied separator is not directly dependent on the gas flow rate, but on the average velocity of the free surface flow generated inside the separator. Maps of efficiency of gas separation were plotted and showed that liquid flow rate, inclination angle and pressure difference between casing and production pipe outlet are the main variables related to the gas separation phenomenon. The new data can be used for the development of design tools aiming to the optimized project of the pumping system for oil production in directional wells. (C) 2012 Elsevier Inc. All rights reserved.

DEVELOPMENT OF A LOW COST IMPEDANCE TUBE TO MEASURE THE ACOUSTIC ABSORPTION AND TRANSMISSION LOSS OF MATERIALS

Traditional methods of measuring sound absorption coefficient and sound transmission loss of a material are time consuming. To overcome this limitation, normal incidence sound absorption and transmission loss measurement technique was developed. Unfortunately the equipment required for this task is equally expensive. Hence efforts are taken to develop a cost-effective equipment for measuring normal incidence sound absorption coefficient and transmission loss. An impedance tube capable of measure absorption coefficient and transmission loss is designed and built under a budget of $1500 for educational institutes. A background study is performed to gain knowledge and understanding of the normal incidence measurements technique. Based on the literature review, parameters involved such as tube material, source and microphone properties, sample holders, etc. are discussed in depth. Based on these parameters, design options are generated to meet the cost and functionality targets pre-assigned. After selection of materials and components, an impedance tube is built and tested using three fibrous absorption materials for absorption and a barrier for transmission loss performance. These measured results then compared with those obtained with the help of industry recognized Brüel & Kjær impedance tube. The results show performances are comparable, hence validation the new built tube.

Computer simulation for tube-making by the cold roll-forming process

The conventional design of forming rolls depends heavily on the individual skill of roll designers which is based on intuition and knowledge gained from previous work. Roll design is normally a trial an error procedure, however with the progress of computer technology, CAD/CAM systems for the cold roll-forming industry have been developed. Generally, however, these CAD systems can only provide a flower pattern based on the knowledge obtained from previously successful flower patterns. In the production of ERW (Electric Resistance Welded) tube and pipe, the need for a theoretical simulation of the roll-forming process, which can not only predict the occurrence of the edge buckling but also obtain the optimum forming condition, has been recognised. A new simulation system named "CADFORM" has been devised that can carry out the consistent forming simulation for this tube-making process. The CADFORM system applied an elastic-plastic stress-strain analysis and evaluate edge buckling by using a simplified model of the forming process. The results can also be visualised graphically. The calculated longitudinal strain is obtained by considering the deformation of lateral elements and takes into account the reduction in strains due to the fin-pass roll. These calculated strains correspond quite well with the experimental results. Using the calculated strains, the stresses in the strip can be estimated. The addition of the fin-pass roll reduction significantly reduces the longitudinal compressive stress and therefore effectively suppresses edge buckling. If the calculated longitudinal stress is controlled, by altering the forming flower pattern so it does not exceed the buckling stress within the material, then the occurrence of edge buckling can be avoided. CADFORM predicts the occurrence of edge buckling of the strip in tube-making and uses this information to suggest an appropriate flower pattern and forming conditions which will suppress the occurrence of the edge buckling.

Flow processes in a radiant tube burner:combusting flow

This paper describes a study of the combustion process in an industrial radiant tube burner (RTB), used in heat treating furnaces, as part of an attempt to improve burner performance. A detailed three-dimensional Computational Fluid Dynamics model has been used, validated with experimental test furnace temperature and flue gas composition measurements. Simulations using the Eddy Dissipation combustion model with peak temperature limitation and the Discrete Transfer radiation model showed good agreement with temperature measurements in the inner and outer walls of the burner, as well as with flue gas composition measured at the exhaust (including NO). Other combustion and radiation models were also tested but gave inferior results in various aspects. The effects of certain RTB design features are analysed, and an analysis of the heat transfer processes within the burner is presented.

Travel Marketing: Industry Relationships and Benefits

In the discussion - Travel Marketing: Industry Relationships and Benefits - by Andrew Vladimir, Visiting Assistant Professor, School of Hospitality Management at Florida International University, the author initially states: “A symbiotic relationship exists among the various segments of the travel and tourism industry. The author has solicited the thinking of 37experts and leaders in the field in a book dealing with these relationships and how they can be developed to benefit the industry. This article provides some salient points from those contributors.” This article could be considered a primer on networking for the hospitality industry. It has everything to do with marketing and the relationships between varied systems in the field of travel and tourism. Vladimir points to instances of success and failure in marketing for the industry at large. And there are points of view from thirty-seven contributing sources here. “Miami Beach remains a fitting example of a leisure product that has been unable to get its act together,” Vladimir shares a view. “There are some first class hotels, a few good restaurants, alluring beaches, and a splendid convention center, but there is no synergism between them, no real affinity, and so while visitors admire the Fontainebleau Hilton and enjoy the food at Joe's Stone Crabs, the reputation of Miami Beach as a resort remains sullied,” the author makes a point. In describing cohesiveness between exclusive systems, Vladimir says, “If each system can get a better understanding of the inner workings of neighboring related systems, each will ultimately be more successful in achieving its goals.” The article is suggesting that exclusive systems aren’t really exclusive at all; or at least they shouldn’t be. In a word – competition – drives the market, and in order for a property to stay afloat, aggressive marketing integrated with all attendant resources is crucial. “Tisch [Preston Robert Tisch, currently – at the time of this writing - the Postmaster General of the United States and formerly president of Lowe’s Hotels and the New York Visitors and Convention Bureau], in talking about the need for aggressive marketing says: “Never...ever...take anything for granted. Never...not for a moment...think that any product or any place will survive strictly on its own merits.” Vladimir not only sources several knowledgeable representatives in the field of hospitality and tourism, but he also links elements as disparate as real estate, car rental, cruise and airlines, travel agencies and traveler profiles to illustrate his points on marketing integration. In closing, Vladimir quotes the Honorable Donna Tuttle, Undersecretary of Commerce for Travel and Tourism, “Uniting the components of this industry in an effective marketing coalition that can compete on an equal footing with often publicly-owned foreign tourism conglomerates and multi-national consortia must be a high priority as the United States struggles to maintain and expand its share of a rapidly changing global market.”

A look into diversity in the radio and music industry in Spain

UNESCO’s approval of the Convention on the Protection and Promotion of the Diversity of Cultural Expressions (UNESCO, 2005) has been an important element in catalyzing any attempt to measure the diversity of cultural industries (UIS, 2011). Within this framework, this article analyzes the relations between the music and radio industries in Spain from a critical perspective through the analysis of available data on recorded music offer and consumption (sales lists, radio-formula lists, the characteristics of the phonographic and radio markets) in different key moments due to the emergence of new formats and devices (CDS, Mp3, Internet).The main goal of this work is to study the evolution of the Spanish record market in terms of diversity from the end of the 1970s to the present, through the study of radio music hits lists and, the business structure of the phonographic and radio sectors, and phonograms top sales

Evaluation of Cross Correlation Technique to Measure Flow in Pipes of the Oil Industry

The present work is concerned with the use of the cross correlation technique to measure delay time between two simulated signals displaced with respect to time, in order to develop a cross correlator system that will be used to measure the water and oil pipes flowrate in which the detection system is composed by two external low intensity radiation sources located along the tube and two NaI(Tl) gamma-ray detectors. The final purpose of the correlator system is to use the natural disturbances, as the turbulence in the own flow rather than to inject radioactive tracers to the fluid flow as usually is carried out. In the design of this correlator is evaluated the point-by-point calculation method for the cross correlation function in order to produce a system accurate and fast. This method is divided at the same time in three modes of operation: direct, relay and polarity.