Simplified method of estimating efficiency of radiant and convective heating systems
This paper investigates the thermal performance of radiant and convective heating systems in a house and proposes a simplified method for evaluating the efficiency of these systems. The characteristics of the systems--heat transfer on enclosed surfaces, temperature and velocity distribution--were examined both by experiment in a full-scale experimental room and by numerical analysis. Convective heat transfer was calculated using a two-equation turbulent model along with radiant analysis. The following conclusions were obtained: (1) With the convective heating system, convective heat transfer amounts to more than 70% of the total heat exchange. With radiant heating, the convective heat exchange is approximately half of the total heat exchange; (2) When convective heat exchange is dominant, the heat loss through poorly insulated windows is larger than when radiant heat exchange is dominant. (3) A simplified method to estimate the efficiency of radiant and convective heating systems is proposed. The simplified formula, which uses operative temperature as a criterion for thermal comfort, can give the ratio of heat load between convective and radiant systems that attains the same operative temperature.
- Research Organization:
- Sekisui House Ltd., Kyoto (JP)
- OSTI ID:
- 20104810
- Resource Relation:
- Conference: ASHRAE Winter Meeting, Dallas, TX (US), 02/05/2000--02/09/2000; Other Information: PBD: 2000; Related Information: In: ASHRAE Transactions 2000; Volume 106, Part 1, 929 pages.
- Country of Publication:
- United States
- Language:
- English
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