The need of realistic models to evaluate the availability of multi-state, multi-output plants is felt in many advanced industries such as the nuclear, aerospace, oil and chemical ones. Indeed, often the complexity of the plant and of its maintenance and recon guration policies is such to render unfeasible its reliability/availibility evaluation by analytical models. In this paper we consider th...

This tutorial explains the surge phenomenon as well as the precursors of surge and the damage that surge can cause to the equipment. Then, methods to keep the compressor system from surge, i.e., modern surge control systems, are discussed. This includes the necessary instruments, algorithms used, as well as the piping layout required. Sizing considerations for valves and other system components...

The twin-screw compressor is constantly attaJ.ninq hiqher performance due to new rotor profiles, new rotor manufacturing technology and new designs. Besides this, new refrigerants as well as new lubricants can be expected on the market. Therefore there is always a need to update performance data. To m1nimize the number of test points and still receive representative data, there 1s a need of an ...

During hot seasons the inlet temperature of Nitrogen increases, as a result compressor consumes more power for compressing a specific mass ratio of fluid and consequently total energy consumption of the compressor increases as well. In this research, a three stage centrifugal compressor with intercooler was modeled thermodynamically in order to decreases the energy consumption of the compressor...

Directed Energy Weapon (DEW) systems in a pulse operation mode dissipate excessively large, transient waste heat because of their inherent inefficiencies. The heat storage system can store such a pulsed heat load not relying on oversized systems and dissipate the stored heat over time after the pulse operation. A compressor-driven metal hydride heat storage system was developed for efficient, c...

The air compressor plays an extremely important role in the production of air separation. It provides the required specifications of compressed air for the follow-up air separation processes. It is difficult for an air compressor system to achieve the on-site production requirements because it is a time-varying, delay and nonlinear complex system. Articles for air compressor control system desi...

In this article torque assisted anti-surge control (TASC), a compressor anti-surge control system based on model predictive control (MPC) is presented. TASC is implemented on an embedded system for the control of compressor stations with electrical variable-speed drives (VSD) which are used in applications such as natural gas transportation via pipelines. The manipulated variables of the propos...

Abstract We study combinatorial structures in large-scale mixed-integer (nonlinear) programming problems arising gas network optimization. propose a preprocessing strategy exploiting the observation that large part of complexity arises certain subnetworks. Our approach analyzes these subnetworks and structure flows within order to provide alternative models with stronger can be exploited by off...