Documents disponibles écrits par cet auteur

A comprehensive model of a miniature-scale linear compressor for electronics cooling / Craig R. Bradshaw in International journal of refrigeration, Vol. 34 N° 1 (Janvier 2011) 

Public ISBD [article]  in International journal of refrigeration > Vol. 34 N° 1 (Janvier 2011) . - pp. 63-73 Titre : A comprehensive model of a miniature-scale linear compressor for electronics cooling Titre original : Modèle extensif d'un compresseur linéaire miniaturisé utilisé pour refroidir les composants des systèmes électroniques Type de document : texte imprimé Auteurs : Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur ; Suresh V. Garimella, Auteur Année de publication : 2011 Article en page(s) : pp. 63-73 Note générale : Génie Mécanique Langues : Anglais (eng) Mots-clés : Linear  compressor  Compressor  model  Electronic  components  Cooling  Miniature-compressor Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : A comprehensive model of a miniature-scale linear compressor for electronics cooling is presented. Linear compressors are appealing for refrigeration applications in electronics cooling. A small number of moving components translate to less theoretical frictional losses and the possibility that this technology could scale to smaller physical sizes better than conventional compressors. The model developed here incorporates all of the major components of the linear compressor including dynamics associated with the piston motion. The results of the compressor model were validated using experimental data from a prototype linear compressor. The prototype compressor has an overall displacement of approximately 3 cm3, an average stroke of 0.6 cm. The prototype compressor was custom built for this work and utilizes custom parts with the exception of the mechanical springs and the linear motor. The model results showed good agreement when validated against the experimental results. The piston stroke is predicted within 1.3% MAE. The volumetric and overall isentropic efficiencies are predicted within 24% and 31%, MAE respectively. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700710002240 [article] A comprehensive model of a miniature-scale linear compressor for electronics cooling = Modèle extensif d'un compresseur linéaire miniaturisé utilisé pour refroidir les composants des systèmes électroniques [texte imprimé] / Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur ; Suresh V. Garimella, Auteur . - 2011 . - pp. 63-73. Génie Mécanique Langues : Anglais (eng) in International journal of refrigeration > Vol. 34 N° 1 (Janvier 2011) . - pp. 63-73 Mots-clés : Linear  compressor  Compressor  model  Electronic  components  Cooling  Miniature-compressor Index. décimale : 621.5 Energie pneumatique. Machinerie et outils. Réfrigération Résumé : A comprehensive model of a miniature-scale linear compressor for electronics cooling is presented. Linear compressors are appealing for refrigeration applications in electronics cooling. A small number of moving components translate to less theoretical frictional losses and the possibility that this technology could scale to smaller physical sizes better than conventional compressors. The model developed here incorporates all of the major components of the linear compressor including dynamics associated with the piston motion. The results of the compressor model were validated using experimental data from a prototype linear compressor. The prototype compressor has an overall displacement of approximately 3 cm3, an average stroke of 0.6 cm. The prototype compressor was custom built for this work and utilizes custom parts with the exception of the mechanical springs and the linear motor. The model results showed good agreement when validated against the experimental results. The piston stroke is predicted within 1.3% MAE. The volumetric and overall isentropic efficiencies are predicted within 24% and 31%, MAE respectively. DEWEY : 621.5 ISSN : 0140-7007 En ligne : http://www.sciencedirect.com/science/article/pii/S0140700710002240

A comprehensive model of a novel rotating spool compressor / Craig R. Bradshaw in International journal of refrigeration, Vol. 36 N° 7 (Novembre 2013) 

Public ISBD [article]  in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1974–1981 Titre : A comprehensive model of a novel rotating spool compressor Titre original : Modèle complet de compresseur innovant à bobine rotative Type de document : texte imprimé Auteurs : Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur Année de publication : 2014 Article en page(s) : pp. 1974–1981 Note générale : Refrigeration Langues : Anglais (eng) Mots-clés : Spool  compressor;  Comprehensive  model;  Novel  compressor;  Geometry  model Résumé : A comprehensive simulation model of a novel rotating spool compressor is presented. The spool compressor provides a new rotary compression mechanism with easily manufactured components. A detailed analytical geometry model of the spool compressor is presented, which includes the geometry of the vane. This geometry model is included in an overall comprehensive compressor model that includes sub-models for friction, leakage, and heat transfer. The results of the comprehensive model were validated using experimental data from a prototype compressor. The prototype compressor has an overall displacement of 23.9 cm3, and was operated using R410A as the working fluid. The model predicts the volumetric efficiency, discharge temperature, and shaft power of the prototype compressor to within 3.13% MAE, 16.5 K and −13.2 W average deviation, respectively. The trends and spread in the data indicate that additional effort should be focused on the operation of the active sealing elements within the compressor. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700713001680 [article] A comprehensive model of a novel rotating spool compressor = Modèle complet de compresseur innovant à bobine rotative [texte imprimé] / Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur . - 2014 . - pp. 1974–1981. Refrigeration Langues : Anglais (eng) in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1974–1981 Mots-clés : Spool  compressor;  Comprehensive  model;  Novel  compressor;  Geometry  model Résumé : A comprehensive simulation model of a novel rotating spool compressor is presented. The spool compressor provides a new rotary compression mechanism with easily manufactured components. A detailed analytical geometry model of the spool compressor is presented, which includes the geometry of the vane. This geometry model is included in an overall comprehensive compressor model that includes sub-models for friction, leakage, and heat transfer. The results of the comprehensive model were validated using experimental data from a prototype compressor. The prototype compressor has an overall displacement of 23.9 cm3, and was operated using R410A as the working fluid. The model predicts the volumetric efficiency, discharge temperature, and shaft power of the prototype compressor to within 3.13% MAE, 16.5 K and −13.2 W average deviation, respectively. The trends and spread in the data indicate that additional effort should be focused on the operation of the active sealing elements within the compressor. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700713001680

Linear compressors for electronics cooling / Craig R. Bradshaw in International journal of refrigeration, Vol. 36 N° 7 (Novembre 2013) 

Public ISBD [article]  in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 2007–2013 Titre : Linear compressors for electronics cooling : energy recovery and its benefits Titre original : Compresseurs linéaires pour le refroidissement des composants électroniques : récupération d'énergie et avantages Type de document : texte imprimé Auteurs : Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur ; Suresh V. Garimella, Auteur Année de publication : 2014 Article en page(s) : pp. 2007–2013 Note générale : Refrigeration Langues : Anglais (eng) Mots-clés : Linear  compressor;  Reciprocating  compressor;  Capacity  control;  Electronics  cooling Résumé : A comprehensive model of a linear compressor for electronics cooling was previously presented by Bradshaw et al. (2011) then enhanced and used for a sensitivity analysis of the leakage gap, eccentricity, and piston geometry by Bradshaw et al. (2013). The current work utilizes the previously developed model to explore the energy recovery characteristics of a linear compressor as compared to those of a reciprocating compressor. The impact of dead (clearance) volume on both a linear and reciprocating compressor is analyzed. In contrast to a reciprocating compressor the overall isentropic efficiency of the linear compressor remains relatively unaffected by an increase in dead volume up to a certain point. This behavior is attributed to the ability of the linear compressor to recapture the energy of the compressed gas during the expansion process. This characteristic behavior allows a linear compressor to be used for efficient capacity control from roughly 35–100%. En ligne : http://www.sciencedirect.com/science/article/pii/S014070071300025X [article] Linear compressors for electronics cooling = Compresseurs linéaires pour le refroidissement des composants électroniques : récupération d'énergie et avantages : energy recovery and its benefits [texte imprimé] / Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur ; Suresh V. Garimella, Auteur . - 2014 . - pp. 2007–2013. Refrigeration Langues : Anglais (eng) in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 2007–2013 Mots-clés : Linear  compressor;  Reciprocating  compressor;  Capacity  control;  Electronics  cooling Résumé : A comprehensive model of a linear compressor for electronics cooling was previously presented by Bradshaw et al. (2011) then enhanced and used for a sensitivity analysis of the leakage gap, eccentricity, and piston geometry by Bradshaw et al. (2013). The current work utilizes the previously developed model to explore the energy recovery characteristics of a linear compressor as compared to those of a reciprocating compressor. The impact of dead (clearance) volume on both a linear and reciprocating compressor is analyzed. In contrast to a reciprocating compressor the overall isentropic efficiency of the linear compressor remains relatively unaffected by an increase in dead volume up to a certain point. This behavior is attributed to the ability of the linear compressor to recapture the energy of the compressed gas during the expansion process. This characteristic behavior allows a linear compressor to be used for efficient capacity control from roughly 35–100%. En ligne : http://www.sciencedirect.com/science/article/pii/S014070071300025X

Modeling of a semi-hermetic CO2 reciprocating compressor including lubrication submodels for piston rings and bearings / Bin Yang in International journal of refrigeration, Vol. 36 N° 7 (Novembre 2013) 

Public ISBD [article]  in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1925–1937 Titre : Modeling of a semi-hermetic CO2 reciprocating compressor including lubrication submodels for piston rings and bearings Titre original : Modélisation d’un compresseur à piston semi-hermétique au CO2, y compris des sous-modèles pour la lubrification des segments de piston et des paliers Type de document : texte imprimé Auteurs : Bin Yang, Auteur ; Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur Année de publication : 2014 Article en page(s) : pp. 1925–1937 Note générale : Refrigeration Langues : Anglais (eng) Mots-clés : Reciprocating  compressor;  Model;  CO2;  Optimization;  Friction Résumé : A comprehensive model for a semi-hermetic CO2 reciprocating compressor is presented. This comprehensive model is composed of three main sub-models simulating the geometry and kinematics, the compression process, and frictional power loss. Valve and leakage sub-models are included in the compression process model. The frictional power loss model includes the friction at the bearings and between the piston ring and cylinder wall. The predicted results of the comprehensive model are validated using external compressor performance measurements of compressor input power and mass flow rate. The mass flow rate and compressor input power are predicted to within 4.03% and 6.43% mean absolute error, respectively, compared to the experimental datum. Additionally, a parametric study is presented which investigates compressor performance as a function of the stroke-to-bore ratio. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700712002770 [article] Modeling of a semi-hermetic CO2 reciprocating compressor including lubrication submodels for piston rings and bearings = Modélisation d’un compresseur à piston semi-hermétique au CO2, y compris des sous-modèles pour la lubrification des segments de piston et des paliers [texte imprimé] / Bin Yang, Auteur ; Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur . - 2014 . - pp. 1925–1937. Refrigeration Langues : Anglais (eng) in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1925–1937 Mots-clés : Reciprocating  compressor;  Model;  CO2;  Optimization;  Friction Résumé : A comprehensive model for a semi-hermetic CO2 reciprocating compressor is presented. This comprehensive model is composed of three main sub-models simulating the geometry and kinematics, the compression process, and frictional power loss. Valve and leakage sub-models are included in the compression process model. The frictional power loss model includes the friction at the bearings and between the piston ring and cylinder wall. The predicted results of the comprehensive model are validated using external compressor performance measurements of compressor input power and mass flow rate. The mass flow rate and compressor input power are predicted to within 4.03% and 6.43% mean absolute error, respectively, compared to the experimental datum. Additionally, a parametric study is presented which investigates compressor performance as a function of the stroke-to-bore ratio. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700712002770

Sensitivity analysis of a comprehensive model for a miniature-scale linear compressor for electronics cooling / Craig R. Bradshaw in International journal of refrigeration, Vol. 36 N° 7 (Novembre 2013) 

Public ISBD [article]  in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1998–2006 Titre : Sensitivity analysis of a comprehensive model for a miniature-scale linear compressor for electronics cooling Titre original : Analyse de la sensibilité d'un modèle exhaustif de compresseur linéaire miniaturisé pour le refroidissement de composants électroniques Type de document : texte imprimé Auteurs : Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur ; Suresh V. Garimella, Auteur Année de publication : 2014 Article en page(s) : pp. 1998–2006 Note générale : Refrigeration Langues : Anglais (eng) Mots-clés : Linear  compressor;  Sensitivity  study;  Miniature  system;  Electronics  cooling;  Loss  analysis Résumé : A comprehensive model of a linear compressor for electronics cooling was previously presented by Bradshaw et al. (2011). The current study expands upon this work by first developing methods for predicting the resonant frequency of a linear compressor and for controlling its piston stroke. Key parameters governing compressor performance – leakage gap, eccentricity, and piston geometry – are explored using a sensitivity analysis. It is demonstrated that for optimum performance, the leakage gap and frictional parameters should be minimized. In addition, the ratio of piston stroke to diameter should not exceed a value of one to minimize friction and leakage losses, but should be large enough to preclude the need for an oversized motor. An improved linear compressor design is proposed for an electronics cooling application, with a predicted cooling capacity of 200 W a cylindrical compressor package size of diameter 50.3 mm and length 102 mm. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700712002356 [article] Sensitivity analysis of a comprehensive model for a miniature-scale linear compressor for electronics cooling = Analyse de la sensibilité d'un modèle exhaustif de compresseur linéaire miniaturisé pour le refroidissement de composants électroniques [texte imprimé] / Craig R. Bradshaw, Auteur ; Eckhard A. Groll, Auteur ; Suresh V. Garimella, Auteur . - 2014 . - pp. 1998–2006. Refrigeration Langues : Anglais (eng) in International journal of refrigeration > Vol. 36 N° 7 (Novembre 2013) . - pp. 1998–2006 Mots-clés : Linear  compressor;  Sensitivity  study;  Miniature  system;  Electronics  cooling;  Loss  analysis Résumé : A comprehensive model of a linear compressor for electronics cooling was previously presented by Bradshaw et al. (2011). The current study expands upon this work by first developing methods for predicting the resonant frequency of a linear compressor and for controlling its piston stroke. Key parameters governing compressor performance – leakage gap, eccentricity, and piston geometry – are explored using a sensitivity analysis. It is demonstrated that for optimum performance, the leakage gap and frictional parameters should be minimized. In addition, the ratio of piston stroke to diameter should not exceed a value of one to minimize friction and leakage losses, but should be large enough to preclude the need for an oversized motor. An improved linear compressor design is proposed for an electronics cooling application, with a predicted cooling capacity of 200 W a cylindrical compressor package size of diameter 50.3 mm and length 102 mm. En ligne : http://www.sciencedirect.com/science/article/pii/S0140700712002356