Zero Internal Heating/Cooling Load Air-Conditioning system Study on Indoor Thermal Environment of an Office Room with the Liquid Cooling Air-conditioning System Li Wang (University of Tokyo, Japan) (leowang19861986@gmail.com)
Evaluation methods for indoor thermal environment The structure of liquid cooling air-conditioning system Q equip Q equip -Q unit -Q panel 0 Sheet-type liquid-cooling unit for heat load of lighting device Liquid-cooling unit for the exhaust heat Interior Zone Chilled beam for the remained heat load of any devices and human body Radiation panel built-in partition for sensible heat load of human body Desiccant Air-handling system (latent heat load processing 1. Heating devices in the officesystem) 2. Heat recovery effect of liquid cooling units Adsorption refrigerator Q in -Q out Air-source 0 Heat Pump Q equip-human -Q unit-human -Q panel-human= 0 High efficiency liquid cooled Heat Pump 4. Heat exchange (High-efficiency between 3. Influence heat source by the heat sink and (Liquid cooling system for the internal load processing&all the task area system and the for waste heat heat recovery) source in task area heat controlling chilled beam system) surround area 2
Experiment conditions Simulation domains Simulation domains Surface heat Exhaust heat Air leakage Heat dissipation from OA equipment Heat dissipation structure on equipment Measurement conditions Temperature:26 Relative humidity:50% Supply velocity:0.04m/s Measurement equipment Q = α T s T n A + C p ρv fan (T fan T a ) + C p ρv vent (T vent T a ) Heat Release Rate from surface Heat Release Rate from exhaust fan Heat Release Rate from air leakage LED lighting Laptop PC Desktop PC Laptop PC Desktop PC back side Exhaust fan USB port Chamber experiment & simulation for determining heat dissipation Radiation shielding curtain Room temperature (Thermocouple) 6 1 7 Heating equipment Surface temperature (Thermocouple & Thermography) 4 5 power inlet Velocity and temp. at inlet (Anemometer) A amount of power input (Clamp-on power meter) 2 8 3 3
Heat dissipation from OA equipment Thermal dissipation properties on the surface of each 2.5 Side 1.9 4.7 Top 6.5 Bottom 1.6 4.5 9.1 Back 1.0 Convection heat transfer(w) 3.5 1.7 Top Bottom 2.1 2.7 Back of display Comparison of the input power and the simulation results LED lighting Laptop PCRadiation Desktop PC Radiation Convection Radiation Convection Convection 2.1 Back of main body 1.6 0.7 0.5 Front of display 9.3 6.8 6.2 Radiation heat transfer(w) Input 投入電力 power[w] Heat 表面からの発熱 release rate from surface[w] 量 [W] Heat 排気口からの発 release rate from exhaust fan [W] 熱量 [W] Heat 隙間換気による release rate from air-leakage [W] 発熱量 [W] 7.7 Side of main body 0.6 0.4 Front of main body Estimate of the amount of heat release rate from air-leakage It is very difficult to determine the air volume and temperature of air-leakage to estimate the difference between the input power and simulation results 0 20 40 60 80 100 120 4
Overview of developed heat recovery units Details of the heat recovery units Target equipment LED lighting Laptop PC Desktop PC Multifunction Printer Heat recovery method 1) Cooling plate 1) Cooling plate 2) Liquid-air heat exchanger 1) Liquid-air heat exchanger 2) Heat recovery sheet 1) Liquid-air heat exchanger Installation method Attaching to the heat sink of the LED module(back side) Installing the cooling plate under the laptop, Attaching the Liquid-air heat exchanger to a outlet of computer Attaching the Liquid-air heat exchanger to a outlet of computer, Installing the heat recovery sheet to the back surface of the display Surrounding the MFP by the hood fitted with the liquid-air heat exchanger 5
Overview of developed heat recovery units Introduction of the heat recovery unit Heat recovery device for uniform heating equipment Heat recovery device for un-uniform heating equipment LED module モジュール Radiation 放射パネル panel Heat 熱回収ユニット recovery unit [Device for lighting] <Drawn Cup heat exchanger> ドロンカップ熱交換器 <exhaust 排気ファン fan> [Study of the heat recovery device for a MFP] [Device for laptop PC] [heat recovery device for a MFP(hood type)] [Device for desktop PC] 6
Overview of developed heat recovery units Installation of liquid cooling heat recovery devices Case of laptop PC Case of MFP Partition (built-in radiation panel) Exhaust fan Fin-coil type Heat exchanger Drawn cup Heat exchanger Cooling plate Case of desktop PC Partition (built-in radiation panel) Heat recovery hood (Forced convection type) Fin-coil type Heat exchanger Heat recovery sheet Drawn cup Heat exchanger Heat recovery hood (Natural convection type) 7
熱回収量 [W] amount of heat recovery[w] amount of heat recovery[w] Performance of the heat recovery device in workspace Sensitivity analysis on the performance of the heat recovery device 熱回収量 [W] 100.0 80.0 60.0 40.0 20.0 放射パネルのみ通水 Only radiation panel 液冷ユニットのみ通水 Only liquid cooling unit 放射パネルと液冷ユニット通水 Radiation panel & Liquid cooling unit 100.0 y = 5.98x + 46.879 R² = 0.9166 80.0 100.0 80.0 60.0 y = 5.6119x + 25.407 R² = 0.8832 y = 2.5754x + 27.508 R² = 0.8824 y = 2.7406x + 0.5818 R² = 0.7818 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Temperature difference between cold water and 冷水温度と室温の温度差 the room temperature[ ] 40.0 (a) Measurement results of laptop PC 20.0 熱回収量 [W] 60.0 40.0 20.0 y = 5.2205x + 37.624 R² = 0.9589 y = 2.8041x + 1.8504 R² = 0.8867 y = 5.98x + 46.879 R² = 0.9166 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Temperature difference y between = 5.2205x cold + water 37.624 and 冷水温度と室温の温度差 the room temperature[ ] R² = 0.9589 (b) Measurement results of desktop PC y = 2.8041x + 1.8504 R² = 0.8867 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 冷水温度と室温の温度差 [ ] (c) Measurement results of MFP (Natural convection type) (d) Measurement results of MFP (Forced convection type) 8
Thermal effects on the human body in the workspace Experiments with Thermal manikin - Evaluation by the equivalent temperature(iso 14505-2) t eq t s Q h cal t s is the surface temperature; t eq is the temperature of the standard environment; Q is the measured convective and radiative heat loss during the actual conditions; h cal is the combined heat transfer coefficient, determined during calibration in a standard environment. Radiation 放射パネル panel 液冷熱回収ユニット Liquid cooling unit Overview of experiments Metrics Measurement Vertical temperature of temp. Surface temperature of radiation panel Measurement of heat recovery Human body heat Air temp & humidity Inlet and outlet water temperature Cold water flow rate Surface temperature (each parts) Sensible heat dissipation (each parts) Measuring equipment Vaisala HM70 T-type thermocouple (floor, center, ceiling) T-type thermocouple (front and rear each 1 point) PT100 Float flow meter Thermal manikin Thermal manikin Case Standard environment 1 or 2 1 or 2-(A) 1 or 2-(B)-( ア ) OA equipment Laptop PC or Desktop PC Power off Cooling device condition Not operation Water flow condition Not operation - 19 1 or 2-(B)-( イ ) Only radiation panel 21 1 or 2-(B)-( ウ ) 23 Laptop PC or 1 or 2-(C)-( ア ) 19 Desktop PC 1 or 2-(C)-( イ ) Only liquid cooling unit 21 Power on 1 or 2-(C)-( ウ ) 23 1 or 2-(D)-( ア ) 19 Radiation panel & 1 or 2-(D)-( イ ) 21 Liquid cooling unit 1 or 2-(D)-( ウ ) 23-9
Temperature of the water flow 23 Temperature of the water flow 21 Temperature of the water flow 19 Thermal effects on the human body in the workspace Effects of equivalent temperature by operation condition and water temperature Case of laptop PC Case of desktop PC [ ] 27.0 1-(A) 1-(B)-( ア ) 1-(C)-( ア ) 1-(D)-( ア ) [ ] 27.0 2-(A) 2-(B)-( ア ) 2-(C)-( ア ) 2-(D)-( ア ) 26.5 26.5 26.0 25.5 25.0 24.5 24.0 26.0 25.5 25.0 24.5 24.0 [ ] 27.0 1-(A) 1-(B)-( イ ) 1-(C)-( イ ) 1-(D)-( イ ) [ ] 27.0 2-(A) 2-(B)-( イ ) 2-(C)-( イ ) 2-(D)-( イ ) 26.5 26.5 26.0 25.5 25.0 24.5 24.0 26.0 25.5 25.0 24.5 24.0 [ ] 27.0 1-(A) 1-(B)-( ウ ) 1-(C)-( ウ ) 1-(D)-( ウ ) [ ] 27.0 2-(A) 2-(B)-( ウ ) 2-(C)-( ウ ) 2-(D)-( ウ ) 26.5 26.5 26.0 25.5 25.0 24.5 24.0 26.0 25.5 25.0 24.5 24.0 10
Thank you Li Wang (University of Tokyo, Japan) (leowang19861986@gmail.com)
熱回収量 [W] amount of heat recovery[w] amount of heat recovery[w] Performance of the heat recovery device in workspace Sensitivity analysis on the performance of the heat recovery device 熱回収量 [W] 100.0 80.0 60.0 40.0 20.0 放射パネルのみ通水 Only radiation panel 液冷ユニットのみ通水 Only liquid cooling unit 放射パネルと液冷ユニット通水 Radiation panel & Liquid cooling unit 100.0 y = 5.98x + 46.879 R² = 0.9166 80.0 100.0 80.0 60.0 y = 5.6119x + 25.407 R² = 0.8832 y = 2.5754x + 27.508 R² = 0.8824 y = 2.7406x + 0.5818 R² = 0.7818 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Temperature difference between cold water and 冷水温度と室温の温度差 the room temperature[ ] 40.0 (a) Measurement results of laptop PC 20.0 熱回収量 [W] 60.0 40.0 20.0 y = 5.2205x + 37.624 R² = 0.9589 y = 2.8041x + 1.8504 R² = 0.8867 y = 5.98x + 46.879 R² = 0.9166 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 Temperature difference y between = 5.2205x cold + water 37.624 and 冷水温度と室温の温度差 the room temperature[ ] R² = 0.9589 (b) Measurement results of desktop PC y = 2.8041x + 1.8504 R² = 0.8867 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 冷水温度と室温の温度差 [ ] (c) Measurement results of MFP (Natural convection type) (d) Measurement results of MFP (Forced convection type) 12