Progress of research

• Application of IEC in Denmark (Michal, Denmark group)

The presentation introduced the application of IEC system in Denmark, and found evaporative cooling system has 10% better overall climate score. This is mainly attributed to the reduced electricity use redirected towards low-CO2 heat production from district heating in summer. And evaporative cooling system has 52% better climate score contribution for material use.

• IEC/DEC applications in China (Xiaoyun Xie, China group)

The presentation aimed to introduce several cases which use IEC/DEC applications in public buildings in dry regions and applications in data center. The public building cases including an IEC case in hotel, a case in exhibition building and a case in station. The cases use in data center including a case with cold water storage tank, and a case in northern China without freezing in winter.

Chinese team will provide detail analysis of these cases and choose different typical applications to compose the final report.

• Feasibility analysis of district cooling systems using IEC (Alanis Zeoli, et al, Belgium group)

Cases study of IDCs project: including the monitoring data and the simulation in Belgium condition of a system. The presentation shows the feasibility analysis of the system, using the performance indicators.

• Modeling of IEC water chiller process (Jiale Fan, China group)

The presentation introduced the modeling of IEC water chiller and IEC air cooler, gives the heat and mass transfer principle and specific formulas of the two processes, and utilizes the method of difference for modeling. For the IEC water chiller, simulation calculations were carried out using EES software, and for the IEC air cooler, simulation calculations were carried out using matlab software.

• Modeling of IEC/DEC processes (Belgium group)

Built a MATLAB generalized model for IEC/DEC processes and validate the generic model with literature data. The model can be adapted to different configurations, and several HEX can be combined to create new configuration.

Final report outlines of subtasks.

• Real applications of IEC/DEC processes. (Alireza Afshari, Mahmood)

For the final report of real applications of IEC/DEC processes, the case collection is continuing, the follow-up works for each country is as following:

Belgium: already provide IEC/DEC system cases and will add analysis information to the system.

China: will choose 2-3 typical cases to the final report, and can offer a typical case in Devis, USA.

Egypt: Omar remains connection, will connect him later to get more cases.

Algeria: may lack of real cases, just simulations works, the detail will connect Chadi to make sure, the French team may can provide new cases.

Italy: may provide the device performance information for air coolers.

Spain: will offer the information of a system case later.

Turkey: Not active, may cannot get more information.

France: will get information soon but may be difficult to offer cases.

Japan: the climate is too wet, so we cannot get suitable cases in operation.

Feasibility analysis. (Xiaoyun Xie)

• Part 1: Feasibility analysis methods

          Definition of feasibility: Fully independent applied: Partially independent applied: fully combined with other technologies.

          Analysis indicators: wet bulb efficiency; dew point efficiency.

          The feasibility analysis work: Macro feasibility: dout<din; wet bulb efficiency & dew point efficiency <1; non-feasible hours <150h, fully independent applied, 150h< non-feasible hours <300h, partially feasible; select specific IEC/DEC systems; 300h< non-feasible hours, fully combined with other technologies.

          For different IEC/DEC techs, the value of the indicators could be given under different climate conditions, and using feasible NTU, to see if they could meet the indicators demand the first part given.

          Compare different IEC/DEC process structures, including IEC/DEC air coolers, IEC/DEC water chillers, to choose the suitable IEC/DEC processes for different type of buildings under different climates. If the value of indicators of one IEC/DEC process is much higher than the demand value, it could be more suitable.

          Performance analysis

• Part 2: Analysed cases of each country

          The second part is the analysed cases of each country, which are calculated for different cities in each country according to the methods given in the first part. In this part, we need each group to give the results of the feasibility analysis for their country.

          What needs to be given is:

1. Calculate the macro feasibility analysis of some cities using the methods.
2. Calculate the indicator value for specific processes.
3. Compare the most suitable process for each city.
4. Since the evaporative cooling process is different in each country, the focus of the case study in each country can be adjusted appropriately.

• Spain

In the last annex meeting, the macro-feasibility of the three cities has been given, and further calculations need to be done for the feasibility of specific processes to get the most applicable processes.

The feasibility analysis of the specific processes: dew point IEC air cooler could be extended to other cities and other countries.

• Italy

Give the results of the feasibility analysis, including macro-feasibility of different cities, indicator of specific processes and performance comparison of processes.

The feasibility analysis of the specific process: cross IEC air cooler could be extended to other cities and other countries.

• France

In the last annex meeting, the macro possibilities for the two cities were given as well as the number of unfeasible hours under a specific process. The report can be written based on the results of the study, following the case given below.

The feasibility analysis of the specific process: combined dew point IEC air cooler could be extended to other cities and other countries.

• Denmark

The cooling process can be presented in terms of partial infeasibility, first analyzing the macro-feasibility in Denmark, and then further describing the specific process in terms of partial infeasibility. In the case of partial practicability, it is necessary to consider whether to modify the judgment indicator.

Performance analysis (Stefano De Antonellis)

The chapter focuses on IEC/DEC device and on its performance. It doesn't deal with device integration at systém level and device modeling: More specifically, the chapter:

Deals with analysis of different IEC technologies (air and water codiing) and minor analysis about DEC devices (used in some configurations of IEC).

Provides (qualitative/quantitative ‘(when possible) information’ about” effects on performance of:

1. Heat exchanger design
2. Humidification system design
3. Operating conditions

Chapter contributions and time schedule

• Contributions:

DEC: Italy.

IEC air chiller (conventional): Italy

IEC air chiller (regenerative): Spain

IEC water chiller: China/Belgium

• Time schedule:

07/24: Definition of general aspects (common to all chapters)

10/24: Draft of 1EC air chiller to be used-as reference

02/25: Draft of entire chapter

Links to other chapters

• DEC/IEC system description: in this chapter
• Nomenclature: common to all chapters
• Terminology: common to all chapters
• Performance indicators: common to all chapters

General aspects to be discussed.

• Chapters order and content:
• Text format (font, size, spacing, structure...)
• Figure/graph format (size, Matlab/Excel standard)
• Psychrometric chart standard (format, Mollier?)
• References format (for each chapter)
• Chapter reviewers

Modeling (Vincent Lemort)

Abstract

Introduction

• purpose of simulation
• type of simulation

Simulation boundary conditions

• Weather data
• Reference cooling loads

Simulated IEC/DEC technologies

• Classification of IEC/DEC technologies
• Coupling of IEC/DEC with buildings
• Control strategies.
• Key Performance Indicators
  • At component level
  • At equipment level
  • At system level
• Presentation of performance

Modelling and simulation of IEC systems integrated with buildings.

• Questionnaire about modeling and simulation tools
• Modeling of IEC technologies
  • Modeling of components
  • Modeling of equipment’s

Water chillers: China can write this section and provide codes/procedures (EES and MATLAB)

• Simulation of IEC technologies
• Simulation of case studies
  • Simulation of DECS (Uliege)
  • Simulation of IEC chillers (China)
• Guidelines and conclusions
• Role of Uliege
  • Ensure uniformity in the way to present the models of systems, the way to describe equations, inputs/outputs/parameters.

Division of labor

• Each group in this Annex responsible for different parts of final reports.

	Report I: Real cases collection	Report 2: Feasibility analysis	Report 3: Performance analysis	Report 4: Simulation analysis
Belgium	1~2 application cases, IEC air coolers, 1, finished, 2nd, Dec,1st, 2024	Analysis of IDCs system, Oct, 1st, 2024	Cooling water, IEC air cooler, to be confirmed Dec, 1st, 2024	Simulation tool, April, 2025 Desiccant cooling, IEC air coolers, Cooling towers, Dec, 1st, 2024, modeling
China	A review of all projects, 2~3 in detail, 1, modified, July,1st, 2nd, 3rd, Dec, 1st, 2024	IEC/DEC technologies under China weather conditions, Dec 1st, 2024	IEC water chiller performance, Dec, 1st ,2024	IEC water chiller, modeling, EES, matlab, simulation results Dec, 1st, 2024
Denmark	1 application case, 1, small modification, Dec, 1st, 2024	Cooperated with Belgium group	Review the report	Review the report
France	Algeria, to be confirmed	To be confirmed	To be confirmed	Algeria, to be confirmed
Italy	Review the report	IEC applied in Data centers, IEC air coolers, Dec, 1st, 2024	Introduction, IEC/DEC air coolers, lab testing, Draft, Oct, 1st	Verification of data with simulation result, Desiccant wheel, IEC air cooler, review work, Possible date, Dec, 1st, 2024 Review the report
Spain	1 possible case, Dec, 1st, 2024	IEC applied in Spain climate conditions, Dec, 1st, 2024	IEC regenerative coolers, lab testing, Dec, 1st, 2024	Transys modeling for IEC air cooler, simulation results, Desiccant combined with IEC, comparison,  Dec, 1st, 2024
Other countries	Turkey, Japan, UK, contacting

Schedule of the next activities

• Urgent task:

Unified definition and nomenclature, each group send a file to Xiaoyun, June 22nd.

To give a draft file, July 15th.

Short meeting to discuss, Sept. 9th

• Future actions:

workshop and meeting

Next workshop	Reims, France, Oct. The date and location will be confirmed as soon as possible, no later than the end of June.
Possible webinar	during ISHPC 2024 (9.1~9.4, China, Beijing), organizing an open webinar(9.3,9.4, 8:00~9:00). Presentations: Michal, Alanis, Not sure: Francisco, Roberta, company colleagues, Luca and colleagues, Online: Vincent, All, Alanis,
2025 workshop I	Spain, April, the data and location will be confirmed, no later than the end of November.
2025 workshop II	Xinjiang, China, Sept. the date and location will be confirmed no later than March April.
International conference of IEC/DEC techs	Xinjiang, China, Sept. together with the second workshop of 2025.

 

Contact information

• Vincent Lemort

  vincent.lemort@uliege.be

• Xiaoyun Xie

xiexiaoyun@tsinghua.edu.cn
Building Energy Research Center, Tsinghua University, Beijing, China.

• Yijie Liu

liuyijie19@mails.tsinghua.edu.cn
Building Energy Research Center, Tsinghua University, Beijing, China.

• Jiale Fan

fjl22@mails.tsinghua.edu.cn
Building Energy Research Center, Tsinghua University, Beijing, China.