Optimal valve location in long oil pipelines

We address the valve location problem, one of the basic problems in design of long oil pipelines. Whenever a pipeline is depressurized, the shutoff valves block the oil flow and seal the damaged part of the pipeline. Thus, the quantity of oil possibly contaminating the area around the pipeline is determined by the volume of the damaged section of the pipeline between two consecutive valves. Then, ecologic damage can be quantified by the amount of leaked oil and the environmental characteristics of the accident area. Given a pipe network together with environmental characteristics of the area, and given a number of valves to be installed, the task is to find a valve location minimizing the maximal possible environmental damage. In this paper we present a complete framework for fast computing of an optimal valve location.environmental economics ;

Optimal Sectioning of Hydrocarbon Transport Pipeline by Volume Minimization, and Environmental and Social Vulnerability Assessment

PresentationSectioning is one of the key mitigation strategies in pipeline transport of liquid hydrocarbons. The valves located along pipelines reduce the maximum volume that may be spilled, decreasing economic, social and environmental losses. Defining the location and number of valves in a specific pipeline section is a challenge due to the countless combinations of these two design components (i.e., where and how many valves). In this work, we tackle the valve location problem (VLP) for sectioning. To solve the problem, we use an optimization approach which assesses the number and location of valves to minimize environmental and social consequences. This problem is modeled as a shortest path problem and it considers the maximum volume that could be spilled as well as environmental and social issues. To estimate and quantify the damages (environmental and social) a new framework is proposed. We present a case study for sectioning in a pipeline of Colombia; the problem is solved using a Bellman-Ford algorithm with CPU times up to 32 s. The results show reductions around 75% of the maximum possible spilled volume. The resulting valve configurations cover areas with high vulnerability, guarantying individual risks lower than the acceptable risk on all populated areas

Studi Karakteristik Volume Tabung Udara Dan Beban Katup Limbah Terhadap Efisiensi Pompa Hydraulic Ram

A community that live far away from electricity power source has a problem in moving water from low to a higher location. One option for solving this problem is using hydraulic ram whose energy is the pressure that resulted from water hammer of water that flows into the pump through pipes. In this paper, a study on the effects of air-tube volume and disposal valve weight to the pump efficiency will be conducted and further the optimal setting for those factors that will gain the best efficiency will be determined.. After the experiments and analysis of variance and also response surface regression, resulting that both factors, air-tube volume and disposal valve weight, influence the efficiency as well as interaction between them. The optimal setting for best efficiecy is at 1300 ml tube volume and 400 gram weight to get efficiency of 42.9209%

Досвід видання довідкової літератури товариством „Просвіта“

The work of the gas transmission pipeline system is regulated by the thousands of valveses and other elements of the shut-off valves, located in different places. Information about the current status of each valve, and confidence in its technical serviceability is an important element in the control of pipeline system. There are a number of problems that adversely affect the  valving operation. Principal among them - is the lack of siystematical approach in valving diagnostics. To solve this problem, developed a new approach to the valving diagnostics – multi-level diagnostics. Depending on the level of diagnosis, we get a different amount of information about the object.   The focus is on the 3rd level of diagnosis, which allows to determine the leackages of valves, and identify type of defects quantitatively. This level of diagnosis is regarded as an example of Method «Micropuls». The method «Micropuls» based on the theory of mechanical vibrations and forced with high accuracy to set the time, frequency and spectral characteristics of noise in the details of the valve, and their spatial location and intensity of that in the presence of a system of analysis allows to determine the state of the object, its faults and defects. Micropulse technology is based on the impact on the measured object micropower impulses, records the response and subsequent filtering, decoding and analyzing the data.                    Specially designed calibrated pulses can effectively influence the measured objects (valve) over a wide range of structural dimensions and mounting schemes, regardless of physical location of the valve.

Testing Microfluidic Fully Programmable Valve Arrays (FPVAs)

Fully Programmable Valve Array (FPVA) has emerged as a new architecture for the next-generation flow-based microfluidic biochips. This 2D-array consists of regularly-arranged valves, which can be dynamically configured by users to realize microfluidic devices of different shapes and sizes as well as interconnections. Additionally, the regularity of the underlying structure renders FPVAs easier to integrate on a tiny chip. However, these arrays may suffer from various manufacturing defects such as blockage and leakage in control and flow channels. Unfortunately, no efficient method is yet known for testing such a general-purpose architecture. In this paper, we present a novel formulation using the concept of flow paths and cut-sets, and describe an ILP-based hierarchical strategy for generating compact test sets that can detect multiple faults in FPVAs. Simulation results demonstrate the efficacy of the proposed method in detecting manufacturing faults with only a small number of test vectors.Comment: Design, Automation and Test in Europe (DATE), March 201

The application of Bayesian change point detection in UAV fuel systems

AbstractA significant amount of research has been undertaken in statistics to develop and implement various change point detection techniques for different industrial applications. One of the successful change point detection techniques is Bayesian approach because of its strength to cope with uncertainties in the recorded data. The Bayesian Change Point (BCP) detection technique has the ability to overcome the uncertainty in estimating the number and location of change point due to its probabilistic theory. In this paper we implement the BCP detection technique to a laboratory based fuel rig system to detect the change in the pre-valve pressure signal due to a failure in the valve. The laboratory test-bed represents a Unmanned Aerial Vehicle (UAV) fuel system and its associated electrical power supply, control system and sensing capabilities. It is specifically designed in order to replicate a number of component degradation faults with high accuracy and repeatability so that it can produce benchmark datasets to demonstrate and assess the efficiency of the BCP algorithm. Simulation shows satisfactory results of implementing the proposed BCP approach. However, the computational complexity, and the high sensitivity due to the prior distribution on the number and location of the change points are the main disadvantages of the BCP approac

Gas turbine engine with recirculating bleed

Carbon monoxide and unburned hydrocarbon emissions in a gas turbine engine are reduced by bleeding hot air from the engine cycle and introducing it back into the engine upstream of the bleed location and upstream of the combustor inlet. As this hot inlet air is recycled, the combustor inlet temperature rises rapidly at a constant engine thrust level. In most combustors, this will reduce carbon monoxide and unburned hydrocarbon emissions significantly. The preferred locations for hot air extraction are at the compressor discharge or from within the turbine, whereas the preferred reentry location is at the compressor inlet