Updated on 2022/09/28

写真a

 
VARELA, Richard Jayson
 
Affiliation
Faculty of Science and Engineering, School of Fundamental Science and Engineering
Job title
Assistant Professor(non-tenure-track)

Education

  • 2015.09
    -
    2020.07

    Waseda University   Department of Applied Mechanics and Aerospace Engineering   Doctor of Engineering  

    MEXT Scholarship Awardee

  • 2014.09
    -
    2015.09

    Waseda University   Department of Applied Mechanics and Aerospace Engineering   Research Student  

    MEXT Scholarship Awardee

  • 2010.06
    -
    2012.10

    University of San Carlos   Department of Mechanical and Manufacturing Engineering   Master of Engineering in Mechanical Engineering  

    ERDT Scholarship Awardee

  • 2011.04
    -
    2011.05

    University of the Philippines   Department of Mechanical Engineering   Technology Entrepreneurship  

    ERDT Scholarship Awardee

  • 2004.06
    -
    2009.03

    Eastern Visayas State University   Department of Mechanical Engineering   Bachelor of Science in Mechanical Engineering  

    Cum Laude, DOST Scholarship Awardee

Degree

  • 2020.07   Waseda University   Doctor of Engineering

Research Experience

  • 2021.04
    -
    Now

    Waseda University   School of Fundamental Science and Engineering   Assistant Professor

  • 2018.11
    -
    2021.03

    Waseda University   Research Innovation Center   Research Associate

  • 2014.10
    -
    2018.09

    Waseda University   Department of Applied Mechanics and Aerospace Engineering   Research Assistant

  • 2012.10
    -
    2014.09

    University of San Carlos   Department of Mechanical and Manufacturing Engineering   Instructor

  • 2009.12
    -
    2011.03

    Pentax Cebu Philippines Corporation   Camera Technical Department   Technical Engineer

Professional Memberships

  • 2020.09
    -
    Now

    Ocean Thermal Energy Association

  • 2016.10
    -
    Now

    American Society of Heating, Refrigerating, and Air-Conditioning Engineers

  • 2015.09
    -
    Now

    International Institute of Refrigeration

  • 2015.09
    -
    Now

    Japan Society of Refrigeration and Air Conditioning Engineers

  • 2014.01
    -
    Now

    Philippine Society of Mechanical Engineers

 

Research Areas

  • Fluid engineering

  • Design engineering

  • Control and system engineering

  • Mechanics of materials and materials

  • Manufacturing and production engineering

  • Measurement engineering

  • Thermal engineering

  • Transport phenomena and unit operations

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Research Interests

  • Energy efficiency

  • Fluid mechanics

  • Thermodynamics

  • Thermal Engineering

  • Heat and mass transfer

  • Liquid desiccant air conditioning

  • Absorption and Adsorption

  • Ventilation

  • Heating

  • Refrigeration

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Papers

  • Performance assessment of integrated liquid desiccant dehumidification with vapor-compression system for energy-efficient air conditioning applications

    Mrinal Bhowmik, Siddharth Rath, Richard Jayson Varela, P. Muthukumar, R. Anandalakshmi, Kiyoshi Saito

    Applied Thermal Engineering   216   119118 - 119118  2022.08  [Refereed]

    DOI

  • Experimental wetting performance assessment of water on a surface-treated aluminum fin-tube substrate for performance improvement of heat and mass exchangers

    Richard Jayson Varela, Tatsuki Hosho, Niccolo Giannetti, Jongsoo Jeong, Kiyoshi Saito

    Proceedings of the 15th IIR-Gustav Lorentzen Conference on Natural Refrigerants   ( 0182 )  2022.06  [Refereed]

    Authorship:Lead author, Corresponding author

  • Experimental performance of a three-fluid desiccant contactor using a novel ionic liquid

    Richard Jayson Varela, Niccolo Giannetti, Kiyoshi Saito, Xinming Wang, Hiroshi Nakayama

    Applied Thermal Engineering   210   118343 - 118343  2022.06  [Refereed]

    Authorship:Lead author, Corresponding author

    DOI

  • Design of a Numerical Simulator for Finned-Tube Heat Exchangers with Arbitrary Circuitry

    John Carlo S. Garcia, Niccolo Giannetti, Daryl Anne B. Varela, Richard Jayson Varela, Seiichi Yamaguchi, Kiyoshi Saito, Menandro S. Berana

    Heat Transfer Engineering     1 - 19  2021.11  [Refereed]

    DOI

  • Development of Assessment Techniques for Next-Generation Refrigerantswith Low GWP ValuesFourth report: Efforts and outcomes on heat exchanger optimization in FY 2020

    Niccolo GIANNETTI, John Carlo GARCIA, Richard Jayson VARELA, Yuichi Sei, Koji Enoki, Jongsoo JEONG, Kiyoshi SAITO

    Proceedings of the JSRAE Annual Conference 2021   ( B143 ) 1 - 6  2021.09

  • Start and Stop Behaviors of Vapor Compression Air-Conditioning System Using Non-azeotropic Refrigerant Mixtures

    Shigeki ISHIZAKA, Hideto YAMAKAWA, Richard Jayson VARELA, Jongsoo JEONG, Kiyoshi SAITO

    Proceedings of the JSRAE Annual Conference 2021   ( D114 ) 1 - 6  2021.09

  • Efficiency Improvement of Liquid Desiccant Air Conditioning System

    Tatsuki HOSHO, RichardJayson VARELA, Niccolo GIANNETTI, Jongsoo JEONG, Kiyoshi SAITO

    Proceedings of the JSRAE Annual Conference 2021   ( D315 ) 1 - 6  2021.09

  • CFD investigation of the wetting characteristics of aqueous ionic liquid solution on an aluminum fin-tube substrate

    Richard Jayson Varela, Hifni Ariyadi, Niccolò Giannetti, Jongsoo Jeong, Kiyoshi Saito

    6th IIR Thermophysical Properties and Transfer Processes of Refrigerants   ( 1941 )  2021.09  [Refereed]

    Authorship:Lead author, Corresponding author

    DOI

  • Design optimization of three-fluid desiccant contactor using genetic algorithm

    Tatsuki Hosho, Richard Jayson Varela, Niccolo Giannetti, Jongsoo Jeong, Kiyoshi Saito

    Proceedings of the International Sorption Heat Pump Conference 2021    2021.08  [Refereed]

  • Intermittent operation of vapor compression air-conditioning system using low GWP refrigerant

    Hideto Yamakawa, Takumi Ogiwara, Richard Jayson Varela, Miyaoka Yoichi, Jongsoo Jeong, Kiyoshi Saito

    2nd IIR Conference on HFOs and Low GWP blends    2021.06  [Refereed]

  • Experimental performance analysis and simulation of an internally cooled liquid desiccant air conditioning system using a novel ionic liquid

    Richard Jayson VARELA, Seiichi YAMAGUCHI, Niccolo GIANNETTI, Kiyoshi SAITO, Xin-Ming WANG, Hiroshi NAKAYAMA

    Refrigeration Science and Technology   2020-December   304 - 309  2020.12  [Refereed]

    Authorship:Lead author, Corresponding author

    DOI

  • Liquid Desiccant Air Conditioning System as an Alternative to Vapor Compression System

    Richard Jayson Varela, Seiichi Yamaguchi, Kiyoshi Saito, Masatoshi Harada, Hikoo Miyauchi

    10th International Mechanical Engineering Research Conference    2020.01

    Authorship:Lead author, Corresponding author

  • Transfer Characteristics of a Fin-Tube-type Regenerator for Liquid Desiccant Systems with Ionic Liquid

    Takumi OGIWARA, Richard, Jayson VARELA, Seiichi YAMAGUCHI, Kiyoshi SAITO, Hiroshi NAKAYAMA, Xinming WANG

    The 30th International Symposium on Transport Phenomena    2019.11  [Refereed]

  • A practical heat and mass transfer model between air and ionic liquid solution in an internally cooled dehumidifier with partial wetting

    Richard Jayson VARELA, Niccolo GIANNETTI, Hifni Ariyadi, Seiichi YAMAGUCHI, Kiyoshi SAITO, Xin-Ming WANG, Hiroshi NAKAYAMA

    Refrigeration Science and Technology   2019-August   1685 - 1692  2019.08  [Refereed]

    Authorship:Lead author, Corresponding author

    DOI

  • Semi-theoretical model of the wetting characteristics of aqueous ionic liquid on an aluminium finned-tube desiccant contactor

    Niccolo Giannetti, Richard Jayson Varela, Hifni Ariyadi, Seiichi Yamaguchi, Kiyoshi Saito, Xin Ming Wang, Hiroshi Nakayama

    Refrigeration Science and Technology   2019-August   4616 - 4623  2019.08  [Refereed]

     View Summary

    © 2019 International Institute of Refrigeration. All rights reserved. A new design of an internally cooled desiccant contactor which uses a new ionic liquid (IL) solution as sorptive medium is targeted. To optimise its operative performance, a semi-theoretical model based on a variational thermodynamic principle is developed to predict the film rupture and wetting ability of the IL solution for different values of the IL mass fraction over a comprehensive range of liquid spray density. The minimum Reynolds number Reb allowing the film-like flow configuration and, below this value, the wetted fraction of the solid substrate are firstly formulated on an analytical basis. Successively, the theoretical formulation is used as a reference to minimise deviations between predicted results and measured data by calibrating dedicated characteristic coefficients. Predicted film rupture, wetting ability and wetting hysteresis behaviour are strongly affected by the IL mass fraction and found in good agreement with the measurements.

    DOI

  • Semitheoretical Prediction of the Wetting Characteristics of Aqueous Ionic Liquid Solution on an Aluminum Finned-Tube Desiccant Contactor

    Niccolo Giannetti, Richard Jayson Varela, Hifni Ariyadi, Seiichi Yamaguchi, Kiyoshi Saito, Xin-Ming Wang, Hiroshi Nakayama

    Journal of Fluids Engineering   140 ( 12 )  2018.12  [Refereed]

     View Summary

    This study involves exploring a new design of an internally cooled/heated desiccant contactor by using a new ionic liquid (IL) solution as the sorptive solution. In order to optimize its operative performance, a semitheoretical model based on the principle of minimum energy is developed to predict the film rupture and wetting ability of the IL solution over a comprehensive range of IL mass fraction and flow rates. A first experimental validation of the fundamental equations of the theoretical model is presented and used as a reference to minimize deviations between predicted results and measured data by calibrating dedicated characteristic coefficients. The noteworthy quantitative and qualitative agreement in the whole range of IL mass fractions and flow rates is promising for contributing to the design of optimized system configurations and control strategies.

    DOI

  • Experimental Study on the Finned-tube Internally Cooled Contactor for Liquid Desiccant Air Conditioning Systems with Ionic Liquid

    Takahiro SATO, Richard Jayson VARELA, Seiichi YAMAGUCHI, Kiyoshi SAITO, Hiroshi NAKAYAMA, Xinming WANG

    International Refrigeration and Air Conditioning Conference   ( 2561 ) 1 - 8  2018.07  [Refereed]

  • General correlations for the heat and mass transfer coefficients in an air-solution contactor of a liquid desiccant system and an experimental case application

    Richard Jayson Varela, Seiichi Yamaguchi, Niccolo Giannetti, Kiyoshi Saito, Masatoshi Harada, Hikoo Miyauchi

    International Journal of Heat and Mass Transfer   120   851 - 860  2018.05  [Refereed]

    Authorship:Lead author, Corresponding author

    DOI

  • Experimental investigation of the wetting characteristics of an aqueous ionic liquid solution on an aluminum fin-tube substrate

    Richard Jayson Varela, Niccolò Giannetti, Seiichi Yamaguchi, Kiyoshi Saito, Xin-Ming Wang, Hiroshi Nakayama

    International Journal of Refrigeration   88   472 - 482  2018.04  [Refereed]

    Authorship:Lead author, Corresponding author

    DOI

  • Correlations for the Heat and Mass Transfer Coefficients in a Structured Packed Bed Regenerator

    Richard Jayson VARELA, Seiichi YAMAGUCHI, Niccolò GIANNETTI, Kiyoshi SAITO, Masatoshi HARADA, Hikoo MIYAUCHI

    International Sorption Heat Pump Conference 2017   ( 1154 ) 1 - 2  2017.08

    Authorship:Lead author, Corresponding author

  • Derivation and validation of dimensionless models for the heat and mass transfer coefficients of a structured packed bed dehumidifier

    Varela, Richard Jayson, Yamaguchi, Seiichi, Giannetti, Niccolo, Saito, Kiyoshi, Harada, Masatoshi, Miyauchi, Hikoo

    2nd International Conference on Energy and Indoor Environment for Hot Climates - ASHRAE, Hot Climates     247 - 254  2017.02  [Refereed]

  • Performance Optimization of a Packed Bed Liquid Desiccant Air Conditioning System

    Richard Jayson VARELA, Seiichi YAMAGUCHI, Kiyoshi SAITO, Masatoshi HARADA, Hikoo MIYAUCHI

    Proceedings of the JSRAE Annual Conference 2016   ( D154 ) 1 - 6  2016.09

    Authorship:Lead author, Corresponding author

  • Effect of Gas-Liquid Contactor Structure on the Dehumidification Performance of a Liquid Desiccant System

    Richard Jayson VARELA, Seiichi YAMAGUCHI, Kiyoshi SAITO, Masatoshi HARADA, Hikoo MIYAUCHI

    The Proceedings of the Symposium on Environmental Engineering   2016.26   402 - 402  2016

    Authorship:Lead author, Corresponding author

    DOI

  • Numerical Simulation of CO2 Heat Pump for Hybrid Desiccant Air Conditioning System

    Richard Jayson VARELA, Keisuke OHNO, Seiichi YAMAGUCHI, Kiyoshi SAITO

    Proceedings of the JSRAE Annual Conference 2015   ( D132 ) 1 - 4  2015

    Authorship:Lead author, Corresponding author

  • Design and Simulation of a Double-Skin Roof Module for Day and Nighttime Natural Ventilation

    Richard Jayson Varela, Nicanor Buenconsejo Jr

    Proceedings of the 3rd Annual International Mechanical Engineering Research Conference    2013.02

    Authorship:Lead author, Corresponding author

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Awards

  • MEXT Scholarship Award

    2014.09   Ministry of Education, Culture, Sports, Science and Technology  

  • ERDT Scholarship Award

    2010.10   Engineering Research and Technology Development  

  • DOST Scholarship Award

    2004.04   Department of Science and Technology  

Research Projects

  • Study on the effect of liquid temperature on the wetting ability and wetting characteristics of falling films on fin-tube surfaces

    Waseda University 

    Project Year :

    2022.04
    -
    2023.03
     

    Richard Jayson Varela

  • Development of a New Concept Heat and Mass Exchanger by Surface/Structure Improvement

    New Energy and Industrial Technology Development Organization (NEDO) 

    Project Year :

    2021.04
    -
    2023.03
     

  • Development of Assessment Techniques for Next-Generation Refrigerants with Low GWP Values

    New Energy and Industrial Technology Development Organization (NEDO) 

    Project Year :

    2018.04
    -
    2023.03
     

  • Development of hydrophilic surfaces for wettability improvement of heat and mass exchangers

    Waseda University 

    Project Year :

    2021.04
    -
    2022.03
     

    Richard Jayson Varela

  • Research and development of technology for innovative use of unused heat energy / Research and development of technology for innovative use of unused heat energy

    New Energy and Industrial Technology Development Organization (NEDO) 

    Project Year :

    2015.04
    -
    2021.03
     

  • Development of ultra-energy saving CO2 inverter heat pump vending machine using waste heat

    New Energy and Industrial Technology Development Organization (NEDO) 

    Project Year :

    2014.04
    -
    2016.03
     

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Presentations

  • Numerical Simulation of a Transcritical CO2 Heat Pump under Intermittent Operation for Energy Savings in Vending Machines

    Richard Jayson Varela

    ERICAE2017 

    Presentation date: 2017.10

  • Design and Simulation of a Double-Skin Roof Module for Day and Nighttime Natural Ventilation

    Richard Jayson Varela  [Invited]

    3rd Philippine Society of Mechanical Engineers & General Membership Meeting Technical Seminar 

    Presentation date: 2013.01

Specific Research

  • Development of hydrophilic surfaces for wettability improvement of heat and mass exchangers

    2021  

     View Summary

    The experimental wetting performance and wetting characteristics of water on a plasma-treated aluminum fin-tube substrate have been investigated and was compared with the experimental results of a non-treated material. Static and dynamic contact angles of water on the hydrophilic material were measured and it was found that the static, advancing, and receding contact angles of water on the treated material are 2.1, 2.5, and 3.1 times smaller, respectively, than those on the non-treated material. Surface wetting experiments were carried out at increasing and decreasing flow rate conditions for Reynolds number ranging from 46.1 to 1386.6. The results show that surface wetting on the hydrophilic material improved by as much as 18.8% at increasing flow rate conditions and 63.5% at decreasing flow rate conditions compared to those on the non-treated material at similar flow rates. Results from this study are useful for performance improvement and minimization of heat and mass exchangers.

 

Syllabus

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Teaching Experience

  • Centrifugal Pump Performance Experiment

    Waseda University  

    2022.04
    -
    2023.03
     

  • Advanced Dynamics and Control of Mechanical Systems

    Waseda University  

    2021.04
    -
    2023.03
     

  • Seminar on Dynamics and Control of Mechanical Systems

    Waseda University  

    2021.04
    -
    2023.03
     

  • Control Engineering

    Waseda University  

    2021.04
    -
    2023.03
     

  • Design and Analysis of Engineering Systems

    Waseda University  

    2021.04
    -
    2023.03
     

  • Heat Transfer

    Waseda University  

    2021.04
    -
    2023.03
     

  • Fluid Mechanics

    University of San Carlos  

    2014.06
    -
    2014.09
     

  • Machine Shop

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • Engineering Thermodynamics

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • Differential Equations

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • Integral Calculus

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • Differential Calculus

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • Analytic & Solid Geometry

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • Plane & Spherical Trigonometry

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • Advanced Algebra

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • College Algebra

    University of San Carlos  

    2012.10
    -
    2014.09
     

  • Mechanics of Deformable Bodies

    University of San Carlos  

    2014.04
    -
    2014.05
     

  • Engineering Materials

    University of San Carlos  

    2013.10
    -
    2014.03
     

  • Advanced Engineering Mathematics

    University of San Carlos  

    2013.10
    -
    2014.03
     

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