Gas pipe failure caused by inner corrosion defects is one of the risk factors for the unscheduled shutdown of a plant. The pipes must be inspected to reduce the risk, but this requires a great amount of time and money, since gas pipes are quite long. This research proposes a screening method for the efficient inspection of gas pipes caused by aqueous corrosion. This screening method consists of...

A detailed experimental study of sound propagation in liquids contained by pipes constructed of polymeric materials is discussed. Experiments were conducted with vertically aligned cylinders containing water ensonified at one end by a piston-driven sound source. Significant sound attenuation (as much as 60 dB} was observed in pipes made of flexible polymeric materials, the effect increasing wit...

The problem considered is the Stokes and Navier-Stokes flow through a system of two pipes in the gravity field; inside a vertical pipe there is a free heavy piston. Theoretical analysis, the existence and non-uniqueness of solution, has been completed recently by the authors. Here we present numerical analysis, using finite elements methods, of the stationary state with respect to the angle bet...

The safety of lifelines, as the most important urban facilities, under different conditions highly depends on the safe design and performance of these buried structures. This cannot be achieved unless their actual behaviors are well understood and considered at the designing stage. A new physical model was developed in Amirkabir University of Technology to study the behavior of buried pipes und...

We report results on the synchronization of an organ pipe either by a second pipe or by a loudspeaker, positioned side by side. Classical theory suggests oscillation death for the synchronization of two organ pipes. With our measurements we clearly exclude this scenario. Rather, we identify the aeroacoustical coupling by the oscillating wind sheet at the pipe mouth as the source of a self-regul...

We study the version of the C-PLANARITY problem in which edges connecting the same pair of clusters must be grouped into pipes, which generalizes the STRIP PLANARITY problem. We give algorithms to decide several families of instances for the two variants in which the order of the pipes around each cluster is given as part of the input or can be chosen by the algorithm.

Many stormwater modeling problems consider watersheds comprised of complex flow networks including surfaces, streets, pipes, and channels. Ideally, hydrologic methods would be used to model the accumulation of runoff on surfaces while hydraulic methods would be used to explicitly model the flow in each street, pipe, and channel. In many practical circumstances, however, only the largest pipes a...

District heating networks are used worldwide, especially in Scandinavian countries and also in many other countries, e.g. Germany, Russia, United States, South Korea and China. From an environmental point of view, district heating networks are a good alternative to more traditional building heating systems. In 1970th, the third generation of district heating systems was established on the marke...

Viscoelastic coatings are often used to protect pipelines in the oil and gas industry. However, over time defects and areas of corrosion often form in these pipelines and so it is desirable to monitor the structural integrity of these coated pipes using techniques similar to those used on uncoated pipelines. A common approach is to use ultrasonic guided waves that work on the pulse-echo princip...

Tubular products in pipe mills are produced by different methods in wide range of sizes and materials for various applications . From simple ERW steel tubes to high quality and expensive seamless tubes, depending on the application, different NDT techniques are used extensively. All these tests are implemented to fulfil the required specification or standard as well as for condition monitoring ...