STP660

    Heat Transfer Versus Pitch Angle for Nonventilated, Triangular-Sectioned, Apex-Upward Air-Filled Spaces

    Published: Jan 1978


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    Abstract

    The optimal pitch angle of a nonventilated triangular-sectioned air space, corresponding to a minimum heat transfer (Q) versus pitch angle (θ), was experimentally determined on a laboratory model to be 18 deg inclination for small values of temperature difference (ΔT) appropriate to those that would occur in roof spaces. In a more realistic roof cavity, this optimal pitch would be smaller; it is suggested that full-size nonventilated roofs be designed with pitches near 15 deg.

    Keywords:

    heat transfer, pitch angle, roof, thermal insulation, convection, triangular cavity, thermal conductivity


    Author Information:

    Thirst, TJ
    School of Mechanical Engineering, Cranfield Institute of Technology, Bedford,

    Probert, SD
    School of Mechanical Engineering, Cranfield Institute of Technology, Bedford,


    Paper ID: STP35745S

    Committee/Subcommittee: C16.30

    DOI: 10.1520/STP35745S


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