Invest ISP 2.0, Installation Manual

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The four major factors that impact the pressure drop
：
The quantity of the liquid flowing through the collector •
：
When the diameter and
the roughness of the riser pipe and header pipe fixed, the pressure drop increases
along with the quantity increase of the liquid flowing through the collector.
The diameter of the riser pipe and header pipe for the collector •
：
When the
roughness of the inner surface of the pipe and the liquid quantity is fixed, the
pressure drop increases along with the decrease of the diameter.
The roughness of the inner surface of the riser pipe and header pipe: When the •
liquid quantity and pipe diameter is fixed, the pressure drop increases along with
the increase of the roughness of the pipe’s inner surface.
The liquid viscosity: when other conditions are the same, the pressure drop •
increases along with the viscosity increase of the liquid flowing through the
collector.
How to select the tilt angle α for mounting the collector:
When the solar system is applicable in four seasons: α=β •
When the solar system is used mainly in summer: α=β-10o •
When the solar system is used mainly in winter: α=β+10o •
Note: α——Title angle for mounting the collector •
；
β——Geographical latitude of local position
2. Pressure drop curve for one collector
3. Installation angle
2