Economic Feasibility and Performance Study of a Solar-Powered Absorption Cycle Using Some Aqueous Salt Solutions

1997 ◽  
Vol 119 (1) ◽  
pp. 31-34 ◽  
Author(s):  
I. H. Malik ◽  
M. Altamush Siddiqui
Keyword(s):  
Economic Feasibility ◽  
Operating Conditions ◽  
The Other ◽  
Solar Collectors ◽  
Performance Study ◽  
Wide Range ◽  
And Performance ◽  
Solar Powered ◽  
Economic Analyses ◽  
Absorption Cycle

Economic analyses of solar collectors, for optimizing generator temperatures in the absorption cycle using aqueous solutions of LiBr, LiBr–ZnBr2, LiBr–ZnBr2LiCl, and LiBr–ZnCl2–CaBr2 salts, have been carried out for a wide range of the operating conditions. Ordinary collectors with two glass covers and evacuated-tubular collectors have been selected as the sources of energy for providing hot liquid in the generator of the absorption cycle. Of the four solutions, as the working fluids in the absorption cycles, those having better coefficients of performance are the LiBr/H2O at the low evaporator temperatures, and the (LiBr–ZnBr2–LiCl)/H2O as well as the (LiBr–ZnCl2–CaBr2)/H2O at the high evaporator temperatures. Similarly, costs of the solar collectors are low, at low evaporation temperatures for the LiBr/H2O and at high temperatures for the other two solutions; the (LiBr–ZnBr2)/H2O, on the other hand, have relatively low COP and high operating costs.

Economic analyses and performance study of three ammonia-absorption cycles using heat recovery absorber

1996 ◽  
Vol 37 (4) ◽  
pp. 421-432 ◽  
Author(s):  
Saghiruddin ◽  
M. Altamush Siddiqui
Keyword(s):  
Heat Recovery ◽  
Performance Study ◽  
Ammonia Absorption ◽  
And Performance ◽  
Economic Analyses

scholarly journals CFD Study of Nozzle Configurations for Ultra High Bypass Engines

1993 ◽  
Author(s):  
H. Zimmermann ◽  
R. Gumucio ◽  
K. Katheder ◽  
A. Jula
Keyword(s):  
Engine Performance ◽  
Operating Conditions ◽  
Aerodynamic Design ◽  
Thrust Coefficient ◽  
Optimum Range ◽  
Installation Effects ◽  
Wide Range ◽  
And Performance ◽  
Aircraft Aerodynamics ◽  
Bypass Ratio

Performance and aerodynamic aspects of ultra-high bypass ratio ducted engines have been investigated with an emphasis on nozzle aerodynamics. The interference with aircraft aerodynamics could not be covered. Numerical methods were used for aerodynamic investigations of geometrically different aft end configurations for bypass ratios between 12 and 18, this is the optimum range for long missions which will be important for future civil engine applications. Results are presented for a wide range of operating conditions and effects on engine performance are discussed. The limitations for higher bypass ratios than 12 to 18 do not come from nozzle aerodynamics but from installation effects. It is shown that using CFD and performance calculations an improved aerodynamic design can be achieved. Based on existing correlations, for thrust and mass-flow, or using aerodynamic tailoring by CFD and including performance investigations, it is possible to increase the thrust coefficient up to 1%.

Uncertainty Analysis of Inflow Conditions on an HPT Gas Turbine Nozzle: Effect on Particle Deposition

2020 ◽  
Author(s):  
R. Friso ◽  
N. Casari ◽  
M. Pinelli ◽  
A. Suman ◽  
F. Montomoli
Keyword(s):  
Gas Turbine ◽  
Energy Efficient ◽  
Gas Turbines ◽  
Particle Deposition ◽  
Operating Conditions ◽  
Wide Range ◽  
And Performance ◽  
Gas Turbine Nozzle ◽  
The Impact ◽  
Inflow Conditions

Abstract Gas turbines (GT) are often forced to operate in harsh environmental conditions. Therefore, the presence of particles in their flow-path is expected. With this regard, deposition is a problem that severely affects gas turbine operation. Components’ lifetime and performance can dramatically vary as a consequence of this phenomenon. Unfortunately, the operating conditions of the machine can vary in a wide range, and they cannot be treated as deterministic. Their stochastic variations greatly affect the forecasting of life and performance of the components. In this work, the main parameters considered affected by the uncertainty are the circumferential hot core location and the turbulence level at the inlet of the domain. A stochastic analysis is used to predict the degradation of a high-pressure-turbine (HPT) nozzle due to particulate ingestion. The GT’s component analyzed as a reference is the HPT nozzle of the Energy-Efficient Engine (E3). The uncertainty quantification technique used is the probabilistic collocation method (PCM). This work shows the impact of the operating conditions uncertainties on the performance and lifetime reduction due to deposition. Sobol indices are used to identify the most important parameter and its contribution to life. The present analysis enables to build confidence intervals on the deposit profile and on the residual creep-life of the vane.

Performance Study of a Mixed Flow Impeller Covering an Unsteady Flow Field

1992 ◽  
Vol 206 (2) ◽  
pp. 83-93 ◽  
Author(s):  
S Sarkar
Keyword(s):  
Axial Flow ◽  
Rotating Stall ◽  
Operating Conditions ◽  
Performance Study ◽  
Mixed Flow ◽  
Pump Impeller ◽  
Wide Range ◽  
Reversal Flow ◽  
Flow Through ◽  
Flow Pump

The results presented here are part of a detailed programme measuring the aerodynamics of a high specific speed mixed flow pump impeller over a wide range of operating conditions, including its behaviour in the unsteady stalled regime. The aim is to elucidate the physics of the flow through such an impeller. The noticeable features are the formation of part-span rotating stall cells having no periodicity and organized structure at reduced flow and also the shifting positions of reversal flow pockets as the flowrate changes. Measurements of loss and its variation with span-wise positions and flowrates enable the variation of local efficiency to be determined. The overall flow picture is similar to that expected in an axial flow impeller, though the present impeller displays a narrow stall hysteresis loop almost right through its operating range.

Analytical Modeling and Performance Study of a Cross Flow Air Dehumidifier Using Liquid Desiccant

2014 ◽  
Vol 875-877 ◽  
pp. 1205-1213 ◽  
Author(s):  
Mohamed M. Bassuoni
Keyword(s):  
Numerical Solutions ◽  
Removal Rate ◽  
Cross Flow ◽  
Operating Conditions ◽  
Maximum Deviation ◽  
Performance Study ◽  
Liquid Desiccant ◽  
Mass Transfer Processes ◽  
And Performance ◽  
Air Conditioning Systems

The dehumidifier is a key component in liquid desiccant air conditioning systems. Various mathematical models of heat and mass transfer processes inside the dehumidifier are introduced and numerically solved in the literature. Analytical solutions have more advantages than numerical solutions in studying the dehumidifier performance parameters. This paper presents the results from an analytical model for the performance of an adiabatic cross flow liquid desiccant air dehumidifier. Calcium chloride is used as desiccant material in this investigation. Both humidity and temperature effectiveness of the dehumidifier are used to predict the performance of the device under various operating conditions. Good accuracy has been found between analytical solution and reliable experimental results with a maximum deviation of +6.63% and -5.65% in the moisture removal rate. The method developed here can be used in the quick prediction of the dehumidifier performance. The exit parameters from the dehumidifier are evaluated under the effects of variables such as air temperature and humidity, desiccant temperature and concentration and air to desiccant flow rates. The results show that hot humid air and desiccant concentration have the greatest impact on the performance of the dehumidifier.

scholarly journals Current Advances in Ejector Modeling, Experimentation and Applications for Refrigeration and Heat Pumps. Part 2: Two-Phase Ejectors

Inventions ◽  
2019 ◽  
Vol 4 (1) ◽  
pp. 16 ◽  
Author(s):  
Zine Aidoun ◽  
Khaled Ameur ◽  
Mehdi Falsafioon ◽  
Messaoud Badache
Keyword(s):  
Heat Pumps ◽  
Operating Conditions ◽  
Industrial Processes ◽  
Experimental Investigations ◽  
Mixing Enhancement ◽  
Data Generation ◽  
Two Phase ◽  
Wide Range ◽  
Potential Applications ◽  
And Performance

Two-phase ejectors play a major role as refrigerant expansion devices in vapor compression systems and can find potential applications in many other industrial processes. As a result, they have become a focus of attention for the last few decades from the scientific community, not only for the expansion work recovery in a wide range of refrigeration and heat pump cycles but also in industrial processes as entrainment and mixing enhancement agents. This review provides relevant findings and trends, characterizing the design, operation and performance of the two-phase ejector as a component. Effects of geometry, operating conditions and the main developments in terms of theoretical and experimental approaches, rating methods and applications are discussed in detail. Ejector expansion refrigeration cycles (EERC) as well as the related theoretical and experimental research are reported. New and other relevant cycle combinations proposed in the recent literature are organized under theoretical and experimental headings by refrigerant types and/or by chronology whenever appropriate and systematically commented. This review brings out the fact that theoretical ejector and cycle studies outnumber experimental investigations and data generation. More emerging numerical studies of two-phase ejectors are a positive step, which has to be further supported by more validation work.

Index-Based Performance Assessment and Condition Monitoring of a Mobile Working Machine

2005 ◽  
Author(s):  
Vesa Ho¨ltta¨ ◽  
Matti Repo ◽  
Lauri Palmroth ◽  
Aki Putkonen
Keyword(s):  
Performance Assessment ◽  
Condition Monitoring ◽  
Operating Conditions ◽  
Multidimensional Data ◽  
Technical Performance ◽  
Machine Performance ◽  
Wide Range ◽  
Data Driven Approach ◽  
And Performance ◽  
Mobile Working

Real-time performance assessment and condition monitoring are potential new features in mobile working machines that have to run in a wide range of operating conditions. Condition monitoring and performance assessment are needed to be able to proactively correct impending faults before severe failures or machine stoppage occur. This paper presents a data-driven approach for machine performance assessment and condition monitoring based on indices representing the performance of a subsystem. Instead of adding new sensors, the indices are computed using existing data from the machine control system. Metrics for machine performance follow-up are derived from these multidimensional data, which have strong nonlinear correlations in certain measurement variables. Although the indices describe primarily the technical performance of the machine, they have proven to be valuable also in terms of condition monitoring of various machine functions. The indices summarize in a concise and easily comprehensible manner changes in performance.

Exergy Analysis for the Performance of Solar Collectors

1983 ◽  
Vol 105 (2) ◽  
pp. 163-167 ◽  
Author(s):  
M. Fujiwara
Keyword(s):  
Performance Evaluation ◽  
Pressure Drop ◽  
Exergy Analysis ◽  
Operating Conditions ◽  
Exergy Loss ◽  
Optimum Operating ◽  
Solar Collectors ◽  
Optimum Control ◽  
Friction Process ◽  
And Performance

The optimum control and performance evaluation of solar collectors are analyzed from the standpoint of exergy. The pressure drop inside the collector is introduced to the analysis using the Hottel-Whillier model. By treating the friction process as exergy loss, the optimum operating conditions are presented in a simple statement. The maximum capability of collectors is determined and expressed by a relationship among the collector parameters and the environment in which they operates.

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