If ground subsidence or seismic load acts on piping that includes bent pipes, the highest stress often occurs not in a straight section but in a bent section. The author has therefore developed a method of estimating the stress generated by a change in diameter by adding an equation for the diameter change and bending moment to the bent pipe stress calculation equations proposed by Rodabaugh an...

In this work, a multi-objective optimization on novel insulated roof with solar water heating system at low material cost has been carried out through Taguchi based grey relational analysis technique. The novel roofs have concrete, insulating polyurethane, and a channel of water in a metallic pipe tunneling the chromium block. Chromium block is used to conduct more heat to raise the water to re...

In this paper, a non-isothermal flow of a micropolar fluid in a thin pipe with circular cross-section is considered. The fluid in the pipe is cooled by the exterior medium and the heat exchange on the lateral part of the boundary is described by Newton’s cooling condition. Assuming that the hydrodynamic part of the system is provided, we seek for the micropolar effects on the heat flow using th...

This paper presents an overview of possible interference mitigation techniques aiming at increasing the system capacity of broadband multimedia satellite systems. A multi-star network topology using a bent-pipe transparent satellite is assumed. After a general overview, the paper concentrates on the assessment of Linear Precoding techniques for increasing the potential system capacity on the Fo...

This paper investigates the thermal fluid-flow transport phenomena in an axially rotating passage in which twin concentric orifices of different radii are installed. Emphasis is placed on the effects of pipe rotation and orifice configuration on the flow and thermal fields, i.e. both the formation of vena contracta and the heattransfer performance behind each orifice. The governing equations ar...

If an air flow is injected into a liquid fluid, many ambulant air bubbles are formed inside the fluid. Air bubbles move inside the liquid fluid because of the buoyancy force, and the mobility of these air bubbles makes sizable commixture and turbulence inside the fluid. This mechanism was employed to enhance the heat transfer rate of a horizontal double pipe heat exchanger in this paper. Howeve...

A mathematical physical model for dynamic simulation of flow and temperature in district heating networks (DHN) is proposed. The network structure is described by means of a graph-theoretical approach where the network elements are pipe sections, consumers and heat sources. The governing equations for hydraulic flows and heat distribution through pipe networks are presented. In addition, proper...