{"id":2029,"date":"2012-05-23T00:01:15","date_gmt":"2012-05-23T05:01:15","guid":{"rendered":"http:\/\/www.summet.com\/blog\/?p=2029"},"modified":"2012-05-23T01:55:57","modified_gmt":"2012-05-23T06:55:57","slug":"bubble-display-air-pump-test","status":"publish","type":"post","link":"https:\/\/www.summet.com\/blog\/2012\/05\/23\/bubble-display-air-pump-test\/","title":{"rendered":"Bubble Display air pump test"},"content":{"rendered":"<p><iframe loading=\"lazy\" width=\"420\" height=\"315\" src=\"http:\/\/www.youtube-nocookie.com\/embed\/B8-YHcMuPTo?rel=0\" frameborder=\"0\" allowfullscreen><\/iframe><\/p>\n<p>A few things I learned from hands-on experience: <!--more--><\/p>\n<ol>\n<li>If the bubbles are large enough to touch the side of the column, they don&#8217;t form spheres. Instead, they look like a jellyfish or bullet rising in the column. (You have to inject a very small amount of air to get a small round bubble.) I kind of like the visual effect, but if you wanted round bubbles (with water) you might need to go for a column that was larger than 1&#8243;.<\/li>\n<li>The water in the top of the column will rise the same height as the total height of all bubbles rising up in the display. (I guess I hadn&#8217;t fully internalized the story of Archimedes in the bath&#8230;.) This means that if you want to have multiple large bubbles moving through the display, you&#8217;ll need several inches of &#8220;headroom&#8221; at the top, or suffer overflows. (Ask my wet garage floor how I learned this&#8230;)<\/li>\n<li>Because the nozzle is so small, it throws out a stream of bubbles which gather together a few inches above the nozzle. (The bubbles at the front have more drag, so the bubbles behind them catch up until they all form into a single large bubble.) This effect takes a few inches in water, and may take a lot more height in glycerin. <\/li>\n<li>Always buy spare parts. After acrylic welding the bottom on the square 1&#8242; column, I attached a check valve (which dripped). Then I attached a different check valve, which had no problems. McMaster-Carr is running 1 for 2 in the functioning check-valve competition&#8230;.I hope the third one I have also works.<\/li>\n<\/ol>\n<p>After I found a working check-valve, I added an air pump\/motor combo and rigged it up so that I could manually activate it with a switch. I will need to test things out with a microcontroller to test super fast sub-100ms activation times. <\/p>\n<p>Here is a closeup video of the end of the nozzle:<\/p>\n<p><iframe loading=\"lazy\" width=\"420\" height=\"315\" src=\"http:\/\/www.youtube-nocookie.com\/embed\/6lhylKFFu_M?rel=0\" frameborder=\"0\" allowfullscreen><\/iframe><\/p>\n<p>Here is a picture of the pump, check valve, and acrylic column (click to zoom):<br \/>\n<a href=\"http:\/\/www.summet.com\/blog\/wp-content\/uploads\/2012\/05\/column_one_air_pump.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.summet.com\/blog\/wp-content\/uploads\/2012\/05\/column_one_air_pump-300x224.jpg\" alt=\"12 volt air pump, connected to a check valve, connected to the bottom of a column of water in a square extruded acrylic tube\" title=\"column one full setup, check valve and air pump\" width=\"300\" height=\"224\" class=\"alignleft size-medium wp-image-2045\" srcset=\"https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2012\/05\/column_one_air_pump-300x224.jpg 300w, https:\/\/www.summet.com\/blog\/wp-content\/uploads\/2012\/05\/column_one_air_pump-1024x767.jpg 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>A few things I learned from hands-on experience:<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[13],"tags":[109],"class_list":["post-2029","post","type-post","status-publish","format-standard","hentry","category-projects","tag-bubbledisplay"],"_links":{"self":[{"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/posts\/2029","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/comments?post=2029"}],"version-history":[{"count":0,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/posts\/2029\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/media?parent=2029"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/categories?post=2029"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.summet.com\/blog\/wp-json\/wp\/v2\/tags?post=2029"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}