Investigation on transient temperature of a reciprocating compressor based on a two-thermocouple probe

Abstract Measuring transient pressure and temperature simultaneously inside a compressor can lead to a thorough characterization of the thermodynamic process in the compressor. However, the rapid changes in airflow temperature make it difficult to measure these conditions precisely, partly due to large thermal inertia of common thermometers such as thermistors and thermocouples. Measurement of rapid temperature changes requires thermometers that have a time constant of a few microseconds or less. Therefore, in this study, two fine wire thermocouples 18 and 35 μm in diameter, respectively, were prepared in advance. A two-thermocouple probe consisting of these two fine wire thermocouples was then used to measure the transient temperature of airflow in the working chamber of a reciprocating compressor. The temperatures detected by the two-thermocouple probe were used to reconstruct the true temperatures. Mean and fluctuating time constants were both evaluated and used to compensate for the raw temperatures. The estimated mean time constants of the two thermocouples were 9.98 and 29.97 ms at 420 rpm, respectively. The maximum difference between the two reconstructed temperatures was 9.7 °C, with an average value of 2.4 °C. Cycle-by-cycle variations of the transient temperatures were also measured.

[1]  Stephen J. Roberts,et al.  Instantaneous Exhaust Temperature Measurements Using Thermocouple Compensation Techniques , 2004 .

[2]  Masato Tagawa,et al.  Response compensation of fine-wire temperature sensors , 2005 .

[3]  R. Liu,et al.  Heat Transfer Between Gas and Cylinder Wall of Refrigerating Reciprocating Compressor , 1984 .

[4]  J. L. Smith,et al.  Time Resolved Mass Flow Measurement for a Reciprocating Compressor , 1980 .

[5]  Rolf Isermann,et al.  Nonlinear time constant estimation and dynamic compensation of temperature sensors , 2010 .

[6]  H. Pfriem,et al.  Zur Messung veränderlicher Temperaturen von Gasen und Flüssigkeiten , 1936 .

[7]  Brahim Bourouga,et al.  Experimental study of periodic heat transfer coefficient in the entrance zone of an exhaust pipe , 2008 .

[8]  Cesar J. Deschamps,et al.  Thermal Analysis of Reciprocating Compressors - A Critical Review , 2008 .

[9]  Christos N. Markides,et al.  A Framework for the Analysis of Thermal Losses in Reciprocating Compressors and Expanders , 2014 .

[10]  S. Roberts,et al.  Cycle-by-Cycle Variations in Exhaust Temperatures Using Thermocouple Compensation Techniques , 2006 .

[11]  Cesar J. Deschamps,et al.  Development of an In-Cylinder Heat Transfer Correlation for Reciprocating Compressors , 2012 .

[12]  Jiří Hejčík,et al.  Comparison of heat transfer models for reciprocating compressor , 2016 .

[13]  S. Touber,et al.  Modeling of Cylinder Heat Transfer - Large Effort, Little Effect? , 1980 .

[14]  B. G. Shiva Prasad,et al.  Fast Response Temperature Measurements in a Reciprocating Compressor , 1992 .

[15]  W. Hsieh,et al.  Experimental investigation of heat transfer in a high-pressure reciprocating gas compressor , 1996 .

[16]  A. Bejan.  Convection Heat Transfer , 1984 .

[17]  E. B. Qvale,et al.  Instantaneous Heat Transfer to the Cylinder Wall in Reciprocating Compressors , 1972 .

[18]  Akshya Swain,et al.  Identification of Time-Varying Time Constants of Thermocouple Sensors and Its Application to Temperature Measurement , 2009 .

[19]  Cesar J. Deschamps,et al.  Experimental investigation of transient fluid flow and superheating in the suction chamber of a refrigeration reciprocating compressor , 2012 .

[20]  Masato Tagawa,et al.  Two-thermocouple probe for fluctuating temperature measurement in combustion : Rational estimation of mean and fluctuating time constants , 1997 .

[21]  B. G. Shiva Shiva Prasad,et al.  Heat Transfer in Reciprocating Compressors: A Review , 1998, Advanced Energy Systems.