Performance Analysis of Absorption Chillers Using Data Reconciliation

2010 ◽  
Author(s):  
David E. Martinez ◽  
Joan Carles Bruno ◽  
Miguel J. Bagajewicz ◽  
Alberto Coronas
Keyword(s):  
Conservation Laws ◽  
Preliminary Test ◽  
Data Reconciliation ◽  
Operation Performance ◽  
Absorption Chillers ◽  
Whole Plant ◽  
Expected Performance ◽  
Partial Load ◽  
Real Performance ◽  
Using Data

Performance data obtained from measurements of process variables usually do not obey material and energy conservation laws. This is why a data reconciliation process, that is, the adjustment of measured data to obey the conservation laws and other constraints is necessary in order to characterize the real performance of equipment, processes, or the whole plant. The information on the partial load and off-design operation performance of absorption chillers is scarce. Real operation of these units do not always coincides with the expected performance according to the data provided by the manufacturer due to site specific conditions. On the other hand the data reconciliation procedure has been extensively applied mainly only for open cycles with a moderate number of recycle streams. The objective of this work is the development and application of the data reconciliation technique to analyse the performance of absorption chillers using rigorous thermodynamic properties for the calculation of the P-V-T equilibrium properties and enthalpies. We present in this paper the preliminary test results for one of the absorption chiller components, the evaporator.

A Preliminary Test of the Impact of De-Globalization on MNC Performance

2021 ◽  
Vol 17 (2) ◽  
pp. 412-428
Author(s):  
Hilla Peretz ◽  
Michael J. Morley
Keyword(s):  
Organizational Context ◽  
Preliminary Test ◽  
Organizational Level ◽  
Institutional Fit ◽  
Preliminary Examination ◽  
Negative Effect ◽  
Key Dimensions ◽  
Using Data ◽  
The Impact ◽  
The Relationship

ABSTRACTWe offer a preliminary examination of whether national and organizational level contexts amplify or reduce the effects of de-globalization on the performance of MNCs. Theoretically, we borrow ideas from both event system theory and institutional fit to propose a model explicating key dimensions of the relationship between de-globalization, national and organizational context, and MNC performance. We then test our ideas using data assembled from 283 MNCs in 20 countries. We find that while de-globalization has a negative effect on MNC performance, national and organizational level contextual endowments do moderate this relationship. We discuss some implications of our findings and highlight attendant limitations.

An investigation in food process simulation using data reconciliation

1993 ◽  
Vol 17 ◽  
pp. S257-S262 ◽  
Author(s):  
M. Meyer ◽  
H. Pingaud ◽  
M. Enjalbert
Keyword(s):  
Process Simulation ◽  
Data Reconciliation ◽  
Using Data

Using Weather and Schedule based Pattern Matching and Feature based PCA for Whole Building Fault Detection — Part I Development of the Method

2021 ◽  
pp. 1-23
Author(s):  
Yimin Chen ◽  
Jin Wen ◽  
L. James Lo
Keyword(s):  
Fault Detection ◽  
Pattern Matching ◽  
Selection Process ◽  
Principal Component ◽  
Component Level ◽  
Operation Performance ◽  
Modeling Process ◽  
Baseline Status ◽  
Feature Based ◽  
Using Data

Abstract A whole building fault (WBF) refers to a fault occurring in one component, but may cause impacts on other components or subsystems, or arise impacts of significant energy consumption and thermal comfort. Conventional methods which targeted at the component level fault detection cannot be successfully employed to detect a WBF because of the fault propagation among the closely coupled equipment or subsystems. Therefore, a novel data-driven method named weather and schedule-based pattern matching (WPM) and feature based principal component analysis (FPCA) method for WBF detection is developed. Three processes are established in the WPM-FPCA method to address three main issues in the WBF detection. First, a feature selection process is used to pre-select data measurements which represent a whole building's operation performance under a satisfied status, namely baseline status. Secondly, a WPM process is employed to locate weather and schedule patterns in the historical baseline database, that are similar to that from the current/incoming operation data, and to generate a WPM baseline. Lastly, PCA models are generated for both the WPM baseline data and the current operation data. Statistic thresholds used to differentiate normal and abnormal (faulty) operations are automatically generated in this PCA modeling process. The PCA models and thresholds are used to detect WBF. This paper is the first of a two-part study. Performance evaluation of the developed method is conducted using data collected from a real campus building and will be described in the second part of this paper.

scholarly journals Performance Indexes of an Air-Water Heat Pump Versus the Capacity Ratio: Analysis by Means of Experimental Data

Energies ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3391
Author(s):  
Roberto Bruno ◽  
Francesco Nicoletti ◽  
Giorgio Cuconati ◽  
Stefania Perrella ◽  
Daniela Cirone
Keyword(s):  
Heat Pump ◽  
Storage System ◽  
Heat Pumps ◽  
Technical Standards ◽  
Capacity Ratio ◽  
Heating And Cooling ◽  
Performance Indexes ◽  
Real Performance ◽  
Using Data ◽  
Set Up

The spread of near-Zero Energy Buildings (nZEB) involves the employment of high performant air-conditioning plants where renewable sources can be integrated easily. In this context, heat pumps appear as a promising solution given their ability to exploit aerothermal, hydrothermal and geothermal sources and to supply both heating and cooling loads with the same device. In order to evaluate the energy performances in transient conditions, the actual winter (COP) and summer (EER) performance indexes, in the function of the sources’ temperatures and the capacity ratio (CR), have to be available. Nevertheless, heat pump manufactures often provide the trend of the performance indexes in the function of the temperatures of the sources specifically for nominal conditions, whereas the dependence of the performance indexes in the function of CR, that takes into account the part-load operation, is almost always not provided. Alternatively, specific technical standards suggest the use of a correction factor to modify nominal COP and EER for the attainment of the real performance indexes. In this paper, by using data from an experimental set-up equipped with air-water heat pumps, these correlations were tested and tuned. Winter results showed that correction factors suggested by standards have to be modified in the presence of a storage system. In summer, instead, a new correlation was developed to find a function between nominal and actual EERs in the function of CR by exploiting a similar approach employed for the COP calculation.

scholarly journals Partial load efficiency analysis of a CCHP plant with RICE and H2O-LiBr absorption chiller

2019 ◽  
Vol 111 ◽  
pp. 06019
Author(s):  
Gabriel Mărcuș ◽  
Cătălin Ioan Lungu
Keyword(s):  
Thermal Energy ◽  
Thermal Load ◽  
Internal Combustion Engines ◽  
Energy Output ◽  
Cooling Power ◽  
Cooling Load ◽  
Absorption Chillers ◽  
Global Efficiency ◽  
Partial Load ◽  
Office Rooms

This paper presents a model for calculating and analyzing the global efficiency of a trigeneration system (CCHP) using 3 reciprocating internal combustion engines (RICE) as prime mover for heat and electric loads. RICE operate simultaneously and at the same load. The CCHP plant delivering energy for the office buildings of an economic operator includes also 2 absorption chillers with water-lithium bromide solution for air conditioning. The system has been analyzed for RICE partial load operation mode, linking the thermal energy output to the cooling power generation. The amount of thermal energy production is influenced by the required energy for cooling. The total cooling load in the summer is determined by both the indoor office-rooms cooling load and the data center cooling load (the energy dissipated by the data center’s components and electrical circuits). An vapor-compression chiller is operated for cooling peak load. During yearly thermal load variation, RICE are switched on or off, operate at nominal capacity or in partial load mode. The thermal efficiency of each engine changes according to the demanded heating load, determining the global efficiency variation of the trigeneration system.. The electrical efficiency of the system is also dependent on the RICE operating load that leads the electric generators. The EER factor for the absorption chillers results accordingly at partial or nominal load operating mode. The functioning graphics for each system equipment were developed based on the thermal load curve of the RICEs and the global efficiency variation graph of the trigeneration system was plotted. Finally, conclusions resulted regarding the optimal functioning of the studied trigeneration system.

scholarly journals Impact on the Performance of Search and Rescue Team by Cloud-Based Services: A Case Study of TransAsia Flight GE235

2019 ◽  
Vol 267 ◽  
pp. 02004
Author(s):  
Yan-Kai Fu ◽  
Chia-Chiang Lee ◽  
Weilun Huang
Keyword(s):  
Performance Outcomes ◽  
Partial Least Square ◽  
Search And Rescue ◽  
Least Square ◽  
Fire Fighter ◽  
Operation Performance ◽  
Team Members ◽  
Use Of Technology ◽  
Real Performance ◽  
The Government

The purpose of this study is to determine the significant gap between the suitable objective environmental conditions and the real performance outcomes when Taipei fire fighter officers and volunteer fire fighters handled the TransAsia GE235 incident. This study employs the “Unified Theory of Acceptance and Use of Technology (UTAUT)” model to investigate the search and rescue (SAR) team members’ adoption of cloud-based services to improve their SAR performance. This study uses the Partial Least Square (PLS) validation for the research hypotheses. The results show that the Taipei City Fire Department’s SAR team and the Volunteer Fire Fighter team have certain gaps in applying the cloud-based service to improve the incident SAR performance. It is revealed that resources, especially in training/education of the government official team, are significant to performance improvement. Finally, several management implications are presented to improve the SAR operation performance.

Migrants' Social Rights, Ethnicity and Welfare Regimes

2005 ◽  
Vol 34 (4) ◽  
pp. 637-660 ◽  
Author(s):  
ANN MORISSENS ◽  
DIANE SAINSBURY
Keyword(s):  
Welfare States ◽  
Social Rights ◽  
Welfare Regimes ◽  
Initial Attempt ◽  
Expected Performance ◽  
The Social ◽  
The Usa ◽  
Using Data ◽  
The Uk ◽  
The Impact

Comparative welfare state research has devoted little attention to the social rights of migrants or the ethnic/racial dimension, even though societies are becoming more ethnically diverse through international migration. Using data from the Luxembourg Income Study for the UK, the USA, Germany, France, Denmark and Sweden, this article represents an initial attempt to compare the social rights of migrants and citizens across welfare regimes. We examine the substantive social rights of migrants and ethnic minorities by focusing on their participation in social transfer programmes, and the impact of transfers on their ability to maintain a socially acceptable standard of living compared with the rest of the population. The analysis shows that there are major disparities between how migrant and citizen households fare in welfare states, and that the discrepancies widen for migrants of colour. When the analysis is confined to citizen households, the results largely correspond to the expected performance of welfare regimes. However, when migrants are incorporated into the analysis, intra-regime variations stand out in the case of the liberal and social democratic countries.

KL a Evaluation during the course of fermentation using data reconciliation techniques

2000 ◽  
Vol 23 (6) ◽  
pp. 565-573 ◽  
Author(s):  
K. Pouliot ◽  
J. Thibault ◽  
A. Garnier ◽  
G. Acuña Leiva
Keyword(s):  
Data Reconciliation ◽  
Using Data

scholarly journals Variable flow and optimization of chiller loading effect on energy saving for screw vapor compression-single effect absorption hybrid chiller plant in hospital mechanical room ‒ case study: Tehran heart hospital

2021 ◽  
Vol 22 ◽  
pp. 9
Author(s):  
Ronald Boghosian ◽  
Mostafa Mafi ◽  
Mohammad Hassan Panjeshahi ◽  
Abtin Ataei
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Water Flow ◽  
Flow System ◽  
Vapor Compression ◽  
Absorption Chillers ◽  
Partial Load ◽  
Energy Consuming ◽  
Single Effect ◽  
Variable Water

Chiller plants are the most energy consuming system during summer season in residential, commercial and hospital buildings. The highly variable cooling demand of the buildings connected to a hybrid chiller plant included absorption and vapor compression chillers to achieve higher energy efficiencies is one of the important issues. Cooling load sharing strategies and apply the variable water flow system in chiller plant have a significant impact on energy consumption and consequently with more productivity and environmentally protected. This paper examines the behavior and pattern of energy consumption in a hybrid chiller plant that includes a combination of two air-cooled screw vapor compression and three single effect absorption chillers. In order to properly understand the pattern of energy consumption, an existing mechanical room in a hospital in Tehran has been studied for five months, and its energy consumption has been compared with the optimized model. The results indicate that the sequence of the chiller function and the way in which they are placed in the circuit during a partial load, is in highest importance in view point of energy saving also by Applying of variable water flow system for optimized chiller loading the more energy saving is achieved for hybrid absorption and vapor compression chiller plant.

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