Pub Date : 2021-01-01DOI: 10.1007/978-3-030-79139-1_10
Osei-Wusu Achaw, E. Danso-Boateng
{"title":"Cocoa Processing and Chocolate Manufacture","authors":"Osei-Wusu Achaw, E. Danso-Boateng","doi":"10.1007/978-3-030-79139-1_10","DOIUrl":"https://doi.org/10.1007/978-3-030-79139-1_10","url":null,"abstract":"","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85281799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25601
Hooman Rezaei, P. Haley, A. Engeda
The objective of this work was to perform numerical analysis of the flow inside a modified single stage CVHF 1280 Trane centrifugal compressor’s vaneless diffuser and volute. Gambit was utilized to read the casing geometry and generating the vaneless diffuser. An unstructured mesh was generated for the path from vaneless diffuser inlet to conic diffuser outlet. At the same time a meanline analysis was performed corresponding to speeds and mass flow rates of the experimental data in order to obtain the absolute velocity and flow angle leaving the impeller for those operating conditions. These values and experimental data were used as inlet and outlet boundary conditions for the simulations. Simulations were performed in Fluent 5.0 for three speeds of 2000, 3000 and 3497 RPM and mass flow rates of minimum, medium and maximum. Results are in good agreement with the experimental ones and present the flow structures inside the vaneless diffuser and volute.
{"title":"Numerical Analysis of the Flow Inside a Centrifugal Compressor’s Vaneless Diffuser and Volute","authors":"Hooman Rezaei, P. Haley, A. Engeda","doi":"10.1115/imece2001/pid-25601","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25601","url":null,"abstract":"\u0000 The objective of this work was to perform numerical analysis of the flow inside a modified single stage CVHF 1280 Trane centrifugal compressor’s vaneless diffuser and volute. Gambit was utilized to read the casing geometry and generating the vaneless diffuser. An unstructured mesh was generated for the path from vaneless diffuser inlet to conic diffuser outlet. At the same time a meanline analysis was performed corresponding to speeds and mass flow rates of the experimental data in order to obtain the absolute velocity and flow angle leaving the impeller for those operating conditions. These values and experimental data were used as inlet and outlet boundary conditions for the simulations. Simulations were performed in Fluent 5.0 for three speeds of 2000, 3000 and 3497 RPM and mass flow rates of minimum, medium and maximum. Results are in good agreement with the experimental ones and present the flow structures inside the vaneless diffuser and volute.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85636519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25600
Weilin Yang, P. Grant, J. Hitt
Our principle goal of this study is to develop a CFD based analysis procedure that could be used to analyze the geometric tradeoffs in scroll geometry when space is limited. In the study, a full centrifugal compressor stage at four different operating points from near surge to near choke is analyzed using Computational Fluid Dynamics (CFD) and laboratory measurement. The study concentrates on scroll performance and its interaction with a vaneless diffuser and impeller. The numerical results show good agreement with test data in scroll circumferential pressure distribution at different ΛAR, total pressure loss coefficient, and pressure distortion at the tongue. The CFD analysis also predicts a reasonable choke point of the stage. The numerical results provide overall flow field in the scroll and diffuser at different operating points. From examining the flow fields, one can have a much better understanding of rather complicated flow behavior such as jet-wake mixing, and choke. One can examine total pressure loss in detail to provide crucial direction for scroll design improvement in areas such as volute tongue, volute cross-section geometry and exit conical diffuser.
{"title":"A Numerical Study of Volute Design in Centrifugal Compressor","authors":"Weilin Yang, P. Grant, J. Hitt","doi":"10.1115/imece2001/pid-25600","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25600","url":null,"abstract":"\u0000 Our principle goal of this study is to develop a CFD based analysis procedure that could be used to analyze the geometric tradeoffs in scroll geometry when space is limited. In the study, a full centrifugal compressor stage at four different operating points from near surge to near choke is analyzed using Computational Fluid Dynamics (CFD) and laboratory measurement. The study concentrates on scroll performance and its interaction with a vaneless diffuser and impeller.\u0000 The numerical results show good agreement with test data in scroll circumferential pressure distribution at different ΛAR, total pressure loss coefficient, and pressure distortion at the tongue. The CFD analysis also predicts a reasonable choke point of the stage. The numerical results provide overall flow field in the scroll and diffuser at different operating points. From examining the flow fields, one can have a much better understanding of rather complicated flow behavior such as jet-wake mixing, and choke. One can examine total pressure loss in detail to provide crucial direction for scroll design improvement in areas such as volute tongue, volute cross-section geometry and exit conical diffuser.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"9 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81380979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25608
H. Coetzee, L. Liebenberg, J. Meyer
The purpose of this paper was to determine the single phase heat transfer and pressure drop characteristics of an angled spiralling tape inserted into the annulus of a tube-in-tube heat exchanger. Experimental measurements were taken on four setups: a normal tube-in-tube heat exchanger used as a reference and three heat exchangers with different angled spiralling tape inserts. From the results correlations were developed that can be used to predict the heat transfer and pressure drop characteristics. It was concluded that the angled spiralling tape inserts resulted in an increase in the heat transfer and pressure drop characteristics as can be expected.
{"title":"Heat Transfer and Pressure Drop Characteristics of Angled Spiralling Tape Inserts in a Heat Exchanger Annulus","authors":"H. Coetzee, L. Liebenberg, J. Meyer","doi":"10.1115/imece2001/pid-25608","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25608","url":null,"abstract":"\u0000 The purpose of this paper was to determine the single phase heat transfer and pressure drop characteristics of an angled spiralling tape inserted into the annulus of a tube-in-tube heat exchanger. Experimental measurements were taken on four setups: a normal tube-in-tube heat exchanger used as a reference and three heat exchangers with different angled spiralling tape inserts. From the results correlations were developed that can be used to predict the heat transfer and pressure drop characteristics. It was concluded that the angled spiralling tape inserts resulted in an increase in the heat transfer and pressure drop characteristics as can be expected.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74907464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25606
D. Hill, Zhejie Liu, J. Sorokes
The use of a virtual test rig to numerically test turbomachinery hardware can be extremely cost effective if the results obtained are physically correct and relatively accurate. The literature clearly shows that a lot of emphasis has been placed on single component validation optimized for a single operation point. There are few studies, however, that have clearly documented the numerical issues surrounding the modeling of a complete stage of a centrifugal compressor across its operating range. This effort uses a generic low flow stage design to demonstrate the accuracy to expect from the current state-of-the-art technology found in both commercial and research computational fluid dynamics (CFD) software. Even effects stemming from secondary flow paths are considered in this study. For design and off-design operation toward surge, 360-degree transient calculations are compared to those obtained from using the steady state fixed-rotor approximation. Finally, all work is ultimately compared to detailed test data obtained from single stage testing.
{"title":"On Establishing the Limits of a Virtual Test Rig","authors":"D. Hill, Zhejie Liu, J. Sorokes","doi":"10.1115/imece2001/pid-25606","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25606","url":null,"abstract":"\u0000 The use of a virtual test rig to numerically test turbomachinery hardware can be extremely cost effective if the results obtained are physically correct and relatively accurate. The literature clearly shows that a lot of emphasis has been placed on single component validation optimized for a single operation point. There are few studies, however, that have clearly documented the numerical issues surrounding the modeling of a complete stage of a centrifugal compressor across its operating range. This effort uses a generic low flow stage design to demonstrate the accuracy to expect from the current state-of-the-art technology found in both commercial and research computational fluid dynamics (CFD) software. Even effects stemming from secondary flow paths are considered in this study. For design and off-design operation toward surge, 360-degree transient calculations are compared to those obtained from using the steady state fixed-rotor approximation. Finally, all work is ultimately compared to detailed test data obtained from single stage testing.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75855817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25619
Randal M Wenthold
For years in the semiconductor inductor industry the only choice individuals had for microfiltration or ultrafiltration devices consisted of flat sheet membrane manufactured into spiral wound or pleated filtration products. Polysulfone hollow fiber technology has evolved in the medical device industry for use as the highest purity type filtration device available. This unique technology is now available for use in the semiconductor business segment as well with product offerings that may be used in laboratory to large-scale applications.
{"title":"Hollow Fiber Microfiltration and Ultrafiltration Products for High Purity Water Treatment Applications","authors":"Randal M Wenthold","doi":"10.1115/imece2001/pid-25619","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25619","url":null,"abstract":"\u0000 For years in the semiconductor inductor industry the only choice individuals had for microfiltration or ultrafiltration devices consisted of flat sheet membrane manufactured into spiral wound or pleated filtration products. Polysulfone hollow fiber technology has evolved in the medical device industry for use as the highest purity type filtration device available. This unique technology is now available for use in the semiconductor business segment as well with product offerings that may be used in laboratory to large-scale applications.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"77 4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89973917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25603
Y. Biba, D. Hill
Turbocompressor manufacturers as well as customers have a constant need for improved aerodynamic component analysis for production and development environments. These predictive tools have historically been grounded with experimental data. Both hardware and tests costs, however, continue to spiral upward, and the difficulties of obtaining reliable data remain unchanged. This has forced the turbocompressor manufactures to use Computational Fluid Dynamics (CFD) as an alternative approach for conducting stage parametric studies. In order for such an approach to be successful, a clear understanding of the relationship between the traditional performance parameters and the numerical solution has to be achieved. Ultimately, an industry standard similar to the test codes should be established. The focus of this work is to contribute into laying the foundation for such an effort. Based on energy conservation equations the relationships between CFD-based loss calculations and efficiencies are developed and discussed. Example of CFD-based performance prediction and flow field analysis of low flow compressor stage is then presented and directions of future work are outlined. This paper is the first part in a series of two. Second part containing more computational results and comparison with test data will follow.
{"title":"On CFD-Based Performance Calculations of Centrifugal Compressor Stages: Part 1","authors":"Y. Biba, D. Hill","doi":"10.1115/imece2001/pid-25603","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25603","url":null,"abstract":"\u0000 Turbocompressor manufacturers as well as customers have a constant need for improved aerodynamic component analysis for production and development environments. These predictive tools have historically been grounded with experimental data. Both hardware and tests costs, however, continue to spiral upward, and the difficulties of obtaining reliable data remain unchanged. This has forced the turbocompressor manufactures to use Computational Fluid Dynamics (CFD) as an alternative approach for conducting stage parametric studies. In order for such an approach to be successful, a clear understanding of the relationship between the traditional performance parameters and the numerical solution has to be achieved. Ultimately, an industry standard similar to the test codes should be established. The focus of this work is to contribute into laying the foundation for such an effort. Based on energy conservation equations the relationships between CFD-based loss calculations and efficiencies are developed and discussed. Example of CFD-based performance prediction and flow field analysis of low flow compressor stage is then presented and directions of future work are outlined. This paper is the first part in a series of two. Second part containing more computational results and comparison with test data will follow.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84901957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25613
B. Ouazia
An experimental investigation was carried out to provide data on heat transfer coefficient and pressure drop for upward flow of refrigerant 134a in a typical plate heat exchanger. Upflow boiling of R-134a in one channel receives heat from the hot downflow of water in the two adjacent channels. Measurements were conducted on three sets of plates with chevron angles of 0°, 30°, and 60°, and the effects of mean vapor quality, mass flux, and heat flux on the evaporation heat transfer and pressure drop were explored. It was found that the channels with small chevron angle have higher heat transfer than channels with large chevron angle, for both subcooling and vapor quality inlet conditions. It was clear that the heat transfer coefficients were not sensitive to the heat flux but were dependent on the flow conditions (mass velocity and vapour quality). Based on the experimental data, empirical correlations for the evaporation heat transfer enhancement factor and the two-phase pressure drop multipliers were proposed.
{"title":"Evaporation Heat Transfer and Pressure Drop of HFC-134a Inside a Plate Heat Exchanger","authors":"B. Ouazia","doi":"10.1115/imece2001/pid-25613","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25613","url":null,"abstract":"\u0000 An experimental investigation was carried out to provide data on heat transfer coefficient and pressure drop for upward flow of refrigerant 134a in a typical plate heat exchanger. Upflow boiling of R-134a in one channel receives heat from the hot downflow of water in the two adjacent channels. Measurements were conducted on three sets of plates with chevron angles of 0°, 30°, and 60°, and the effects of mean vapor quality, mass flux, and heat flux on the evaporation heat transfer and pressure drop were explored. It was found that the channels with small chevron angle have higher heat transfer than channels with large chevron angle, for both subcooling and vapor quality inlet conditions. It was clear that the heat transfer coefficients were not sensitive to the heat flux but were dependent on the flow conditions (mass velocity and vapour quality). Based on the experimental data, empirical correlations for the evaporation heat transfer enhancement factor and the two-phase pressure drop multipliers were proposed.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87716757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25618
T. Fiadjoe, D. Chau, P. Phelan
As the use of reverse osmosis (RO) machines becomes prevalent in our society, more attention is being paid to reducing their operational and maintenance costs. One method of improving efficiency is by adequate pretreatment of the feed water to the RO system. A proposed alternative to current chemical treatment methods is a novel high-voltage, capacitance-based system that utilizes electrostatic dispersion techniques. This alternative method of treatment was experimentally evaluated and was found to be effective in certain aspects of RO pretreatment. An experimental apparatus was designed based on two nominally identical household RO systems. The two systems were subject to identical, but variable, feed conditions. The technology proved effective in reducing the bacterial contamination levels in an RO system, although it did not completely eliminate the formation of biofilm.
{"title":"Experimental Results on the Application of a High-Voltage Capacitance-Based Technology to Reduce Biofouling in Reverse Osmosis Systems","authors":"T. Fiadjoe, D. Chau, P. Phelan","doi":"10.1115/imece2001/pid-25618","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25618","url":null,"abstract":"\u0000 As the use of reverse osmosis (RO) machines becomes prevalent in our society, more attention is being paid to reducing their operational and maintenance costs. One method of improving efficiency is by adequate pretreatment of the feed water to the RO system. A proposed alternative to current chemical treatment methods is a novel high-voltage, capacitance-based system that utilizes electrostatic dispersion techniques. This alternative method of treatment was experimentally evaluated and was found to be effective in certain aspects of RO pretreatment. An experimental apparatus was designed based on two nominally identical household RO systems. The two systems were subject to identical, but variable, feed conditions. The technology proved effective in reducing the bacterial contamination levels in an RO system, although it did not completely eliminate the formation of biofilm.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91042092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-11-11DOI: 10.1115/imece2001/pid-25604
Hooman Rezaei, P. Haley, A. Engeda
The objective of this work was to establish an advanced testing facility for studying the flow structure and loss mechanism in a single stage centrifugal compressor. A Trane’s CVHF 1280, two stage centrifugal compressor was modified to a single stage for laboratory environment. This modification included new fluid medium, driving motor, inlet and outlet designs. In this study, experiments were performed in order to evaluate the performance of the vaneless diffuser and volute. However, the modifications enable the flow structure investigation in all components of the compressor as well. In addition the testing facility would accommodate installation of the rest of the unit for investigation of the flow in the vaned diffuser and return channel of the two-stage compressor in the laboratory environment. Experiments were performed in three speeds and eight mass flow rates per speed. Static and total pressures were measured at the inlet and outlet of the stage. Static pressure distributions were mapped on the vaneless diffuser and volute casings. These data evaluates the characteristics of these components after the modifications.
{"title":"Modifications of a Two Stage Centrifugal Compressor for the Volute and Vaneless Diffuser Study","authors":"Hooman Rezaei, P. Haley, A. Engeda","doi":"10.1115/imece2001/pid-25604","DOIUrl":"https://doi.org/10.1115/imece2001/pid-25604","url":null,"abstract":"\u0000 The objective of this work was to establish an advanced testing facility for studying the flow structure and loss mechanism in a single stage centrifugal compressor. A Trane’s CVHF 1280, two stage centrifugal compressor was modified to a single stage for laboratory environment. This modification included new fluid medium, driving motor, inlet and outlet designs. In this study, experiments were performed in order to evaluate the performance of the vaneless diffuser and volute. However, the modifications enable the flow structure investigation in all components of the compressor as well. In addition the testing facility would accommodate installation of the rest of the unit for investigation of the flow in the vaned diffuser and return channel of the two-stage compressor in the laboratory environment.\u0000 Experiments were performed in three speeds and eight mass flow rates per speed. Static and total pressures were measured at the inlet and outlet of the stage. Static pressure distributions were mapped on the vaneless diffuser and volute casings. These data evaluates the characteristics of these components after the modifications.","PeriodicalId":9805,"journal":{"name":"Chemical and Process Industries","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2001-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81829844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}