%0 Journal Article
%T Reciprocating Compressor 1D Thermofluid Dynamic Simulation: Problems and Comparison with Experimental Data
%A A. Gimelli
%A A. Rapicano
%A F. Barba
%A O. Pennacchia
%J International Journal of Rotating Machinery
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/564275
%X The authors here extend a 0D-1D thermofluid dynamic simulation approach to describe the phenomena internal to the volumetric machines, reproducing pressure waves¡¯ propagation in the ducts. This paper reports the first analysis of these phenomena in a reciprocating compressor. The first part presents a detailed experimental analysis of an open-type reciprocating compressor equipped with internal sensors. The second part describes a 0D-1D thermofluid dynamic simulation of the compressor. Comparison of computed and measured values of discharge mass flow rate shows a good agreement between results for compression ratio . Then, to improve the model fitting at higher pressures, a new scheme has been developed to predict the blow-by through the ring pack volumes. This model is based on a series of volumes and links which simulate the rings¡¯ motions inside the grooves, while the ring dynamics are imposed using data from the literature about blow-by in internal combustion engines. The validation is obtained comparing experimental and computing data of the two cylinder engine blowby. After the validation, a new comparison of mass flow rate on the compressor shows a better fitting of the curves at higher compression ratio. 1. Introduction 1.1. Background Volumetric compressors, alternative and rotary, represent an element of large utilities in the domestic field as in industrial applications, in particular, the refrigeration cycle [1, 2]. In today¡¯s world, energy optimization is of the utmost importance, therefore, it is crucial to find tools which can support the planning phase to increase the efficiency of these machines. Imagine, that approximately 11% of the produced electrical energy today is destined to power domestic refrigeration [3]. Reported in this paper is a method for the simulation of 0D-1D fluid-dynamic phenomena which occurs in the volumetric machines, noting the results from a study of problems linked to volumetric reciprocating engine, that in the future will be extended also to rotary. For years, the most widely used and reliable approach was the empirical one [4], because of the complexity of physical phenomena that takes place in the thermal machines. This occurs because the functioning at full performance of a volumetric compressor is not stationary but periodic; equations that govern the mass transport in the pipelines are not linear, so they cannot be resolved through an analytic method. However, the development of computing potential and of theoretical-numeric methods suggest a new approach, based on the use of fluid-dynamic models. These
%U http://www.hindawi.com/journals/ijrm/2012/564275/