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This paper describes the design and performance analysis of a chemically recuperated gas turbine powering a ship. The system studied consisted of an efficient steam-generating system, a reforming regenerator, and a gas turbine. Mathematical models were built for the performance analyses. An efficient steam-generating system was designed and the effects of various parameters on the steam generation were studied. The calculations indicate that the steam-generating system can meet the steam requirements for reforming and fresh water needs of the ship. The diesel steam-reforming reaction was adopted for heat recuperation, and the reaction degrees were analyzed under different conditions. It was found that the reforming regenerator recovered heat from the waste gas to reform the fuel leading to improved combustion. The performance analysis shows that the chemically recuperated gas turbine has a higher thermal efficiency and consequently delivers more power. The steam reforming cycle has a low reaction degree and needs to be improved through additional research.

Thermodynamic design methods and performance calculation models for chemical reformers that can be used to recuperate exhaust heat and to improve combustion quality are investigated in this paper. The basic structure of the chemical reformer is defined as series-wound reforming units that consist of heat exchangers and cracking reactors. The CH4-steam reforming reaction is used in the chemical reformers and a universal model of this reaction is built based on the minimization of Gibbs free energy method. Comparative analyzes between the results of the calculation and a plasma-catalyzed CH4-steam reforming reaction experiment verify that this universal model is applicable and has high precision. Algorithms for simulation of series-wound reforming units are constructed and the complexity of the chemical reformers is studied. A design principle that shows the influence of structural complexity on the quantity of recovered heat and the composites of the reformed fuel can be followed for different application scenarios of chemical reformers.

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Gas pulsations within the refrigerant gas cavity is one of the principal noise propagating paths in reciprocating compressors. This paper provide a physical insight to the relationship between the gas pulsations inside the cavity and noise radiation of reciprocating compressors. The refrigerant gas cavity of the test compressor is modeled as a space between concentric spherical shells and analyzed with modal expansion techniques. Gas pulsations within the cavity are mathematically represented as the forcing terms of the inhomogeneous wave equation in spherical coordinates. The pressure distribution inside the cavity is then estimated accordingly. Based on the orthogonality principles, the noise radiation patterns associated with the gas pulsations are predicted. Acoustic modal analysis, directivity test and running speed sensitivity test are conducted to identify the acoustic characteristics of cavity and to verify the analytical model. The experimental results are in good agreement with the prediction of the analytical model. Thus, the concentric, spherical shell model well describes the acoustic characteristics of cavity within the test compressor. This model can also be employed as a design tool to analyze the effects of system parameter variation on overall noise radiation.