Friday, April 26, 2013

Hot body velocimetry. Blow on your finger.

Emflume instrumentation entertainment. from Steve Gough on Vimeo.

Wet your finger.  Blow on it.  You can sense the cooling.

Try it with a dry finger.  You'll probably sense that, too.  Feel the cooling?

Your body works to maintain 37 °C .   Air moving past it at a lower temperature cools it, that's why you sense the cooling of your finger.

Science lit is full of "thermal anemometry"  papers, and you can buy instruments that measure airspeed this way -- a body, usually very small, is heated to a constant temperature, and the power needed to do that is a measure of fluid velocity past it.

I'm calling our work "hot body velocimetry" because there isn't a name for it in the lit, not for water.

We need to measure velocity in our new Emflume, and in our Emriver models.

Getting bloodless instruments to work as well as fingers is not so easy.  Stick your finger in moving water and you'll see.

Monday, April 15, 2013

EGU 2013, more dots on the map, thermal velocimetry.

Meriam at EGU in Vienna last week
Jim, Lily, and Nathan load three Em2 geomodels today

Our Meriam is back from EGU 2013, where she respresented us in her four languages.  She's jet-lagged and exhausted, but bears lots of good news.

Three Em2 models left this afternoon; off to do good things, way more than dots on a map to us.

Jim and I continued work on a thermal velocimeter for our models.  A nifty concept used a lot for air.  Not so easy to apply in water.

I should let this concept go for something simpler, but the physical interactions; thermodynamics, electronics, fluid mechanics, are fascinating.

Notes in instruments for thermal velocimeter R&D

Power-resistance curves for thermistors we're testing
A thermistor being tested in the flume.

Monday, April 8, 2013

Happiness at LRRD.

Today Jim and I made a thermal velocimeter work in our new Emflume. Many hours of work, and a science first.

Lily looked great in her Thai silk tie, busy talking to clients all day.  She was happy to see purchase orders for two Em2 models last Friday.

John Micheal prepped two more Em2s for shipment. We shipped three last week.

And today I made a rack to hold the fifty or so prototyping tools I use most.

A happy day for me.

And we have a booth here this week.  More on that later.