Hello everyone,

I am trying to model Earth-Air tunnels in eQUEST located in atropical,composite climate (New Delhi). Following the last two threadson this issue dated Nov. 2003 and Oct, 2006 (shown below) nothing elseseems to have been discussed, especially relating to modeling thisstrategy in eQUEST? If anyone has had any experience with it thenplease share. I'd appreciate your feedback. Meanwhile, let me try andexplain the system that I am trying to model and how I am approachingit --

Earth-air (horizontal) tunnels utilize 100% outside air as it is blownthrough them. This brings down the temperature as the air is sensiblypre-cooled for the air handling unit. In the hot-dry months the air iseither delivered or is subjected to direct-indirect evap-cooling. Forwarm-humid periods a small portion of the pre-cooled air stream issubjected to DX coil where it drops most of its moisture and is mixedwith the rest of the air stream In principle my strategy will be tomodel ground-source heat exchanger (GSHX) wherein a fluid (water)rejects or gains heat and transfers the benefit to the air handlingunit using 100% OA. I am guessing that the transfer of heat betweenwater-earth via the GSHX and then water-air in the AHU has to be veryefficient to diminish losses incurred and model this system fairlyaccurately. I will finally subtract the pumping energy from the total.Here is the crux, and the questions --

Am I thinking in the right direction?
How does one increase the efficiency ofthe GSHX process to best reflect earth-air heat exchange? The aim as Isaid earlier is to diminish the losses incurred due to the water-earthand water-air processes of the GSHX?

For now, I am tied to eQUEST to solve thisproblem because a large time-consuming part of the model is alreadyaccomplished. However if there is a better way to address this with anyother tool then please do not shy from sharing your knowledge. Manythanks for helping in the past and in advance on this one.

sincerely,

Neeraj Kapoor