Optimal Design Method of Passive and Active Controlling System for Indoor Climate Design with Fluctuating Outdoor Conditions

Transcription

1 Optimal Design Method of Passive and Active Controlling System for Indoor Climate Design with Fluctuating Outdoor Conditions KATO, Shinsuke IIS, Univ. of Tokyo JAPAN, JN3

2 Objective Developing the optimal design method of passive and active controlling systems of indoor climate using GA (MOGAs) and CFD Optimization will be done on the basis of multi-objectives In the study, the rational restrict conditions for searching optimal solutions set (Paleto set) are examined Hybrid Air-conditioning (Combination of Wind induced ventilation and Air-Conditioning) will be dealt with considering windows, room shape, AC conditions, variations of (random) outdoor climate conditions, variations of random indoor conditions

3 Multi-Objective Optimization There are no singular solutions for the multi-objective optimization comfort ability Solution set Daylight Energy use Solar heat Outdoor Temperature Comfort ability Productivity Elements for window design comfort ability Singular Solution Energy use Paleto solutions set Selective solution Inferior solution Element is changed through design process Objectives for window design Object is evaluated quantitatively energy use

4 Approach of Multi-Objective Optimization To get the Paleto solution set with the multi-objective genetic algorism Once the Paleto set is obtained, then the cluster analysis is done for advising possible selective solution to designer Paleto solution set Cluster Analysis Solution set Inferior solutions Understanding Characteristics of Paleto set Understanding the relationship with design variables

5 Paleto Solutions of Daylight, Ventilation and Thermal Environment CLUSTER1 CLUSTER5 CLUSTER2 CLUSTER6 CLUSTER3 CLUSTER7 CLUSTER4 CFD for Thermal Environment Daylight simulation

6 Methodology GA (Genetic Algorithm) and CFD (Computational Fluid Dynamics) are used Searching the optimal design of the hybrid system which uses both passive and active methods for controlling indoor climate strongly affected by fluctuating outdoor conditions and other parameters

7 Research Description Developing the CFD with active controlling of indoor climate for fluctuating outdoor conditions and others The active system adjusts its output to keep the indoor condition at the targeted state (feedback system) We develop the simulation system of indoor climate with the active control for fluctuating outdoor conditions The evaluation of the optima should be done from the viewpoint of energy saving, cost, human comfort, uniformity of daylight and so on (multi-objectives) Applying the methods for hybrid ventilation which utilizes both wind induced cross ventilation and airconditioning with fluctuating outdoor

8 Two Step Optimization Procedure

9 Example of Objective Function The amount of energy-saving sensible heat removed by natural ventilation E(kW) =Cp ρ ΔT Q

10 Examples of Restricting Conditions The average temperature ranges from 23 ºC to 27 ºC in the task region The average air velocity is below 0.5 m/s in the task region The vertical difference in temperature is below 3.5ºC in the task region...

11 Hybrid Air-Conditioning Model

12 Examples of Design Parameters

13 Fluctuating Outdoor Conditions Sampling interval Probability Random variable (ºC) -2σ -σ (M 1.5σ) -σ M (M 0.5σ) M σ (M+0.5σ) σ 2σ (M+1.5σ)

14 GA inquiry

15 Cases Selected in the First Step GA and CFD with coarse grid systems Higher evaluations for the objectives and passing the restrictions Case A Case B Case C

16 Case B is selected in the second step CFD with fine grid systems and highest evaluation for the objectives Provability 34.1% Provability 34.1%