Parabolic Trough Tilt

Hi there, I live in a northern latitude in Canada. When I run the Parabolic Trough model and include some tilt I see less heat output from the field, providing I enter positive values - ie closer to vertical. But when I tilt the trough downward with negative values, like -10 deg the trough output goes up quite a bit. Am I getting valid results? Thanks Allan

Dear Allan,

The collector tilt angle for the parabolic trough model is defined as follows (from SAM's Help system):

The angle of all collectors in the field in degrees from horizontal, where zero degrees is horizontal. A positive value tilts up the end of the array closest to the equator (the array's south end in the northern hemisphere), a negative value tilts down the southern end. SAM assumes that the collectors are fixed at the tilt angle.

Note that this definition is different from the tilt angle input for the photovoltaic models.

Best regards,
Paul.

Boy do I ever appreciate the help you provide. Thanks to all of you. Allan