belated references

some references i forgot to post earlier. mostly pertaining to the mechanics of the thermal trap component of the system.

use of thermal trap material for space heating of non-air conditioned buildings, J. Prakash & E. Carnevale (found on science direct)

performance prediction of two sloar water heaters using a thermal trap, Prakash & E. Carnevale (found on science direct)

infulence of the thermal trap material on teh performance of a roof as an inexpensive collector/storage system, G. N. Tiwari (found on science direct)]

energy citations database document #5066935

energy citations database document #6282908

thermal modeling of a natural convection solar water heating system with a thermal trap collector, N.K. Bansal; Sant Ram; R. Uhlemann, international journal of sustainable energy, volume 2, issue 5 1984, page 425-438

Materials

the assembly shown in the previous post shows a standard IRMA roofing system with a Tyvek ThermaWrap layer between the balast and insulation to contribute to the therma lag effect at the insulation layer (6" of soil has an aproximate R value of 4, where the insulation is much higher).

ThermaWrap features a "Low-e metallized surface" that reflects infrared radiation. this contributes to the heating of the water in the pipes(reflects heat back up to the pipes) and a cooler interior environment. Thermawrap also purportedly has generates an R value of 2 when provided with a minimum of 3/4" air space. we may also be able to use this effect by suspending the ballast by 3/4", decreasing the r loss in the ballast from the pipes

here is the product page for tyvek ThermaWrap:

http://www2.dupont.com/Tyvek_Weatherization/en_US/products/commercial/comm_thermawrap.html

Cut Away of Proposed System and New References

first off is an an illustration showing a cut away of my proposed system



and next are some more resources i have found:

ASPE Codebook

ASHRAE Codebook

BC Building Code 2006

proposal

the following is the proposal to precede the abstract

Re: Proposal to Research the Effectiveness of Utilizing Roof Rainwater as a Source of Greywater in Kamloops

Main Task: Reducing the Cost Of Hot Water Heating via Hot Water Recirc in Ballast Layer of IRMA Roofing Systems

Background: most passive water heating systems are expensive, pre built packaged units. This research looks at using copper hot water reirc piping above the insulation in IRMA roofing as an alternative

typical IRMA performance:

->heat ransmission through ballast

->thermal lag at insulation layer

->inside air temp

IRMA w/ HWR and reflective tyvek layer below pipes

->heat transmission through ballast

->heat relfected by tyvek

->thermal lag at insulation layer

->heat transmitted to HWR system

->inside air temp

Cost/Savings analysis of proposed system

->viable or not

resources:

EDDT 281 Building Services Theory, Walter Prescott, 2009

http://apps.carleton.edu/campus/sustainability/greenroof/assets/GreenRoofExpandedPress21.pdf

http://www.engineeringtoolbox.com/copper-pipe-heat-loss-d_19.html

Introduction

this blog is to catalogue my progress on researching the technical viability of using hot water recirculation pipes in the ballast of IRMA roofing to mitigate energy requirements of water heating

if you have anything to add or questions to ask, feel free to post.

thank you for your interest.