1 / 17

O.Yoshida, M.Andou Tokyo Gas Co., Ltd.

Development of EUC (End User Computing) System for the Design of HVAC ( Heating, Ventilation and Air Conditioning). O.Yoshida, M.Andou Tokyo Gas Co., Ltd. Contents. Introduction Feature of the EUC system Wide variety of DB (data-base) Original user-subroutines Verification of DB

kaye-wright
Download Presentation

O.Yoshida, M.Andou Tokyo Gas Co., Ltd.

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Development of EUC (End User Computing) System for the Design of HVAC(Heating, Ventilation and Air Conditioning) O.Yoshida, M.Andou Tokyo Gas Co., Ltd.

  2. Contents • Introduction • Feature of the EUC system • Wide variety of DB (data-base) • Original user-subroutines • Verification of DB • Conclusions

  3. Introduction • CFD methods have become a promising tool to optimise design parameters of HVAC by predicting thermal environment in buildings. • While many advantage are expected, CFD codes still require lots of expertise and time for designers to model and predict indoor environment. • Wider application of CFD has been expected, in particular, to the field of EUC that designers and even sales engineers can easily take advantage of. An EUC system for the optimal design of HVAC has been developed.

  4. Feature of the EUC System • Utilisation of PHOENICS • Flexible pre-processor • Powerful solver • Easy VR post-processor Uniquely customised to predict indoor environment in faster, more accurate and user-friendly manners • Wide variety of DB (data-base) for the analysis of HVAC • Original user-subroutines • Verification of DB

  5. Q1 Q1 A/C DB A/C type Building DB Wide Variety of DB (Data-base) The system incorporated DB compiled during various cases of predictions and experiments. • The DB provides typical specifications of a variety of air-conditioners and buildings as a set of Q1 files. • It also maintains previous Q1 and PHI files as reference, which can be readily upgraded to predict similar problems .

  6. Original User-subroutines • Along with the DB, series of practical user-subroutines have been developed using GROUND. • These user-subroutines are applicable to predict ideal performance and operating conditions of air-conditioning units under desired optimal thermal environment. • Optimisation of input conditions such as efflux temperature is conducted to obtain desired thermal environment in a room.

  7. Z=0.6m Window Office Room Type (Outside of Temp. = 0 C) Original User-subroutines - ExamplePrediction of Optimal Efflux Temp. • Mean temperature at the height of 0.6m for each of perimeter and interior areas needs to be 22℃ to achieve desired thermal environment. Unit_P(Q=9m3/min) Unit_I1(Q=6)Unit_I2(Q=6) Interior (Area_I) Perimeter (Area_P) • Efflux temperatures are separately controlled with reference to respective area temperature.

  8. Start Tm_start=22 C, Tm_end=22 C, Te_start=40 C EARTH Solution Calculate Tm Te Calculate Rlx (Relax. factor) by Residual of NETSOURCE Tm Te=Te+(Tm_end-Tm)*Rlx LSWEEP ? No Yes End Temperatures. vs. Sweep No. Original User-subroutines - ExampleAlgorithm

  9. Efflux temp ≒ 30.6C Efflux temp ≒ 29.8C Center plane of A/C units Mean temp ≒ 22.0C Mean temp ≒ 22.0C Plane at Z=0.6m Original User-subroutines - ExampleTemperature Distributions

  10. Computation Measurement Verification Verification of DB • Prediction accuracy of DB of the system was verified a-priori, by comparing with detailed measurements. • Know-hows to generate a numerical grids have been compiled to secure practical accuracy with minimum calculation time .

  11. Air-Conditioning unit 3D traverse apparatus Schematic Diagram Model Room Verification of DB - ExampleArtificial Climatic Room

  12. Neighboring Temp. = 10 C Air-Conditioning unit Sink Efflux Temp. = 46C Outside of Temp. = 0 C Living Room Type Verification of DB - ExampleHeating Conditions

  13. Numerical Grid Verification of DB - ExampleNumerical Analysis • PHOENICS 3.2 • Steady states • Rectangular grids 38×32×33 = 40128cells • Elliptic-staggered equation • k-epsilon turbulence model • Hybrid differencing schemes • Boussinesq buoyancy model

  14. Measured Computed Verification of DB - Example Center Plane of Air Conditioner

  15. Verification of DB - Example Center Plane of Model Room Measured Computed

  16. ● Verification of DB - Example Temperature Profiles

  17. Conclusions • An useful EUC system for the optimal design of HVAC has been developed using PHOENICS. • The system incorporated DB for the analysis of HVAC as a set of Q1 files . • Along with the DB, practical user-subroutines have been developed. • Prediction accuracy of the system was verified a-priori, by comparing with detailed measurements. • Computed result with incorporate DB was in good agreement with measured result.

More Related