Thursday, December 19, 2013

The Sterling Heat Engine

#sterlingheatengine by lexly87 aka Duc N. Ly
Instead of a messy process of using steam to make a vacuum beneath a piston, thus causing atmospheric pressure to drive the piston down, Stirling's version (illustrated above) uses the heating and cooling (and thus expansion and contraction) of gas sealed inside the engine to do the piston-driving.  [Thus it's being called the free-piston engine.]  (The Economist November 30th 2013.)  
The Economist issue November 30th, 2013 had a short article on the Sterling Heat Engine. The article appeared in the category of Science and technology.  I want to find the article on line to share here but can't find it yet. The on line link to science is Economist science .

The Stirling engine is named after the inventor and clergyman, Robert Stirling.  He patented the device in 1816, about 200 year old.
One version of the Stirling engine is a free-piston engine but runs backwards as a refrigerator.  It uses mechanical energy as the input (rather than the output) to pump heat away from where it is not wanted.  These specialized fridges chill the infra-red sensors on orbiting telescopes.     

Engineers want to bring free-piston engines to replace Rudolf Diesel's smelly, polluting motors in generators that provide electric power to the tropical villages not yet connected to the grid.
 Advantage one:  like a steam engine, a Stirling is an external-combustion engine, it can run on a variety of fuels.  It can be powered by wood, dried animal dung or anything else that will burn.
Advantage two:  free-piston engine suffers little wear and tear, so it should be able to run for decade without servicing.   

Tuesday, December 17, 2013


#drawings by lexly87 aka Duc N. Ly
#drawings, a photo by lexly87 aka Duc N. Ly on Flickr.
Inspired by theoretical works of other architects and architecture. Perhaps John Hejduk or Walter Pilcher.

 The idea began perhaps 10 years ago.  The drawing for the above dates back to April 14, 2003.  It's drawn on the same material.  The white box came from Pro Photo Supply lab in NW Portland.  They develop medium format films and put them in these wonderful white box that make for nice drawing surfaces.

my behance Architectural-Sketches

West Linn Library Model

Via Flickr:
I found this model at the West Linn Library. It's a wonderful library.  The model was placed in the building about right where you see the view to the trees out back.  It was a surreal experience of seeing the views and looking at the model that represents that experience of the view.  I did not have to project my imagination very far. 


Corvallis Youth Center
Corvallis, Oregon

Tuesday, July 2, 2013