Turbomachinery Control Valves Sizing and Selection

TutorialsTurbomachinery Controls dedicated to centrifugal and axial compressors use several types of control valves, such as: -Antisurge (recycle) valve -Suction throttle valve -Hot-gas bypass valve -Quench control valve As the final control element in its control loop, these control valves are vital to implementing good turbomachinery controls. This tutorial will examine the control objective of each type of valve, its ideal location relative to the turbocompressor and the optimum performance characteristics for the valve. Valve selection criteria and sizing methodologies with examples will be addressed. Recommendations for valve noise abatement will be provided, as well as valve noiseabatement pitfalls that should be avoided will be identified. The possible negative or positive impact of annular seal on rotordynamics of compressors and steam turbines is discussed. The nature of destabilizing forces that can be developed by Asee-through@ and interlocking labyrinths is discussed

Turbomachinery Control Valves Sizing and Selection

TutorialsTurbomachinery Controls dedicated to centrifugal and axial compressors use several types of control valves, such as: -Antisurge (recycle) valve -Suction throttle valve -Hot-gas bypass valve -Quench control valve As the final control element in its control loop, these control valves are vital to implementing good turbomachinery controls. This tutorial will examine the control objective of each type of valve, its ideal location relative to the turbocompressor and the optimum performance characteristics for the valve. Valve selection criteria and sizing methodologies with examples will be addressed. Recommendations for valve noise abatement will be provided, as well as valve noiseabatement pitfalls that should be avoided will be identified. The possible negative or positive impact of annular seal on rotordynamics of compressors and steam turbines is discussed. The nature of destabilizing forces that can be developed by Asee-through@ and interlocking labyrinths is discussed

Refrigeration Compressor Basics For The Oil And Gas Industries

TutorialThis tutorial discusses the design basics for refrigeration compressors, using the 2�section Propane refrigeration configuration as an example. The benefits of incorporating a flash gas Economizer are discussed, as are the various methods of controlling the performance these machines, with the pros and cons for each method analyzed. The proper antisurge control design is developed and correct recycle line arrangements are presented. A case study of incorrect recycle line arrangements for a Single Mixed Refrigeration (SMR) Compressor, and the proposed modifications, is also presented

DEVELOPMENT AND DESIGN OF ANTISURGE AND PERFORMANCE CONTROL SYSTEMS FOR CENTRIFUGAL COMPRESSORS

TutorialThe development and design of control systems for centrifugal and axial compressors is discussed and explanations given to bring together features of control systems on varying machine designs. Potential problems resulting from such differences will be addressed and resolutions offered

Development and Design of Antisurge and Performance Control System for Centrifugal Compressor

TutorialThe development and design of control systems for centrifugal and axial compressors is discussed and explanations given to bring together features of control systems on varying machine designs. Potential problems resulting from such differences will be addressed and resolutions offered

DEVELOPMENT AND DESIGN OF ANTISURGE AND PERFORMANCE CONTROL SYSTEMS FOR CENTRIFUGAL COMPRESSORS

TutorialThe development and design of control systems for centrifugal and axial compressors is discussed and explanations given to bring together features of control systems on varying machine designs. Potential problems resulting from such differences will be addressed and resolutions offered

Compressor Loadsharing Control And Surge Detection Techniques

TutorialCentrifugal compressor trains operating in parallel or series arrangements are complex when it comes to turbomachinery control. Methodologies for controlling compressor trains in these arrangements piping layout considerations to be observed is discussed. Surge in centrifugal and axial compressors often manifests itself as oscillations of flow and pressure, as well as related compressor parameters, such as rotating speed. Many of the devices, which incorporate surge detection function, use either the location of the operating point relative to the Surge Limit Line (SLL) or physical manifestations of surge, such as high rates of changes of selected process signals for identifying surge. This paper analyzes surge signatures collected in the field and outlines several approaches to surge detection using a combination of parameters, such as flow and discharge or suction pressure, based on the type of application

Novel Insights about Synergistic Effect of Zamzam Water with SGL2 Inhibitors on Wound Healing in STZ-Induced Diabetic Rats: The Role of anti-Inflammatory and Proangiogenic Effects

Background: Hyperglycemia usually impairs wound healing by dysregulating the inflammatory response and angiogenesis. This study aimed to examine the synergistic effect of dapagliflozin and Zamzam water (ZW) on the healing of diabetic wounds and to explore their anti-inflammatory and proangiogenic effects. Materials and methods: A full-thickness excisional wound was made on the backs of all groups after two weeks of diabetes induction. Forty rats were divided into five groups, with eight rats per group; Group 1: Control non-diabetic rats; Group II: Untreated diabetic rats; Group III: Diabetic rats drinking ZW; Group IV: Diabetic rats receiving an oral dose of 1 mg/kg dapagliflozin; and Group V: Received both dapagliflozin and ZW. The healing of diabetic wounds was assessed by measuring wound closure, oxidative stress markers, immunohistochemical staining of NF-βB, VEGF, CD34, CD45, Ki-67, and eNOS, gene expression of MMP-9, TGF-β1, EGF-b1, FGF, and Col1A1, protein levels of TNFα, IL-1β, IL6, Ang II, and HIF-1α by ELISA assay, and histological examination with H & E and Masson’s trichrome. Combined treatment with dapagliflozin and ZW significantly (p < 0.05) enhanced the wound closure and antioxidant enzyme level, with apparent histological improvement, and shortened the inflammatory stage of the diabetic wound by decreasing the level of inflammatory markers NF-κB, TNF-α, IL-1β, IL6, and CD45. Therefore, it improved angiogenesis markers VEGF, CD34, eNOS, EGF-β1, FGF, Ang II, and HIF-1α, increasing Ki-67 cellular proliferation. Moreover, it enhanced the remodeling stage by increasing MMP-2, TGF-β1, and Col1A1 levels compared to diabetic rats