I've seen enough with the new Pro shield so it's going in service as the main radiation shield. I'm doing one more test that has nothing to do with the Pro performance by raising the sensor height to 80" (inches) above the ground to avoid the sprinklers this summer. I want to do some overnight low-temperature comparisons against the 5' (foot) Fars to see if the 2 extra feet height make a large enough difference.
I'll probably move back down to 5' shield height after sprinklers are off next fall.
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Yuor radiation shield is cover on the top?
Don't understand the question, sorry.
Glad to see the 7714 test. So how do you keep the fan from getting wet?
Which way does the air flow? Is it pulling from the top down or pushing the air up?
the problem of the davis 7714 (that remain one of the best passive radiation shield in the word) is:
Solar radiation should not be understood only from top to bottom. Solar radiation is from all directions, indirect and direct. The plates of the Davis 7714 are affected not only from above and from the side, but also in their lower part.
Barani, who obviously has a recent project in Davis, understood this by taking advantage of the evidence and knowledge of those who preceded him.
And what did he do?
Practically, in addition to a very well-made helical screen that takes full advantage of the Venturi effect, the sensor has incorporated it into a completely dark room, which receives no light anywhere. In addition, the black parts well arranged along the whole screen internally, allow the screen to block the heat by diffusion and indirect radiation. It does not allow sunlight and heat to pass through it into the inner chamber. That's all...
Davis 7714 has too much space between the plates and lacks the black part. The fan gives the screen a little help, in my case, sometimes even counterproductive perhaps. [ You are not allowed to view attachments ]
