Effective Mistuning Identification Method of Integrated Bladed Discs of Marine Engine Turbochargers

Abstract

Radial turbine and compressor wheels form essential cornerstones of modern internal combustion engines in terms of economy, efficiency and, in particular, environmental compatibility. As a result of the introduction of exhaust gas turbochargers in the extremely important global market for diesel engines, higher engine efficiencies are possible, which in turn reduce fuel consumption. The associated reduced exhaust emissions can answer questions that results from environmentally relevant aspects of the engine development. In shipping, the international Maritime Organisation (IMO) prescribes the step-by-step reduction of nitrogen oxide and other types of emissions. To reduce these emissions, various systems are being developed, in which turbochargers are an important part. The requirements for the reliability and service life of turbochargers are constantly increasing. Turbocharger blade vibration is one of the most important problems to be solved when designing the rotors. In the case of real rotors, so-called mistuning arises, which is a slight deviation of the properties of the individual blades from the design parameters. The article deals with an effective method of mistuning identification for cases of integrated bladed discs of marine engine turbochargers. Unlike approaches that use costly scanning laser Doppler vibrometers, this method is based on using only a simple laser vibrometer in combination with a computational model of the integrated bladed disc. The added value of this method is, in particular, a significant reduction in the cost of laboratory equipment and a reduction in the time required to obtain the results.

Acoustic Method for Estimation of Marine Low-Speed Engine Turbocharger Parameters

“…This results in a change in the flow capacity of the exhaust manifolds as well as the character of the gas internal flow in front of the turbocharger wheel blades. Pulsations might occur, which cause the rotor to vibrate [8][9][10]. An increased level of rotor vibration creates additional loads on turbocharger bearings and reduces their operational life.…”

“…Acoustic control of the turbocharger in operation makes it possible to detect the dangerous tendency for the rotor vibration level to increase and indicates the need to clean the flow channel [8][9][10][11]. In some cases, such control might prevent turbocharger failure, which typically leads to a considerable loss of power and efficiency in the entire engine [1,[11][12][13][14].…”

Numerical Model to Analyze the Physicochemical Mechanisms Involved in CO2 Absorption by an Aqueous Ammonia Droplet

“…Moreover, resources are widely distributed. Another advantage is that ammonia can also reduce other pollutants, including SO 2 and NO x [12][13][14][15][16].…”

Marine Engines Performance and Emissions

“…These papers were developed by 39 authors from The Netherlands, Finland, Sweden, Korea, Slovakia, China, Chile, Ukraine, Poland, and Spain. Most papers discuss emissions from marine engines [1][2][3][4][5][6][7][8][9], and others discuss performance, such as control technology [10], and turbocharger compression [11,12]. Puškár et al [1] and Sui et al [2] analyzed alternative fuels.…”

“…Shen et al [11] developed a marine two-stroke diesel engine MVEM (Mean Value Engine Model) with in-cylinder pressure trace predictive capability and a novel compressor model. Finally, Píštěk et al [12] developed a mistuning identification method of integrated bladed discs of marine engine turbochargers.…”