Six-Stage Closed Loop Pulsating Heat Pipe (CLPHP) Hydrogen Distiller with Speed Controlled Active Fan Cooling

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This is a model of a 6-Stage Closed Loop Pulsating Heat Pipe (CLPHP) Hydrogen Distiller with Speed Controlled Active Fan Cooling. This model uses a 6-stages but can be scaled up to 12-stage, 18-stage, or 24-stages by chaining additional modules.This model was intentionally designed NOT to use Peltier Cooling Modules (also known as Thermo-Electric Coolers TECs) since TECs require both very high current amperage as well as high voltages = High Power Consumption at > 30 Watts and likely over 80 Watts. They are also very expensive and are typically $1 per Watt (per maximum wattage per module) with a single module costing ~ $60 of each module in low volume.This model is based upon a Closed Loop Heat Pipe (CLHP) that is a proven passive form of heat transfer and also uses the very familiar tachometer controlled active cooling convection fans. The fans consume a maximum of 35 mA each x 3 = 105 mA @ 12V for about 1.25 Watts of electrical power. Typical power consumption is likely to be half or less depending upon conversion demands and fan speed which is monitored by (3) individual thermocouples mounted at each heat sink (not shown) and is part of the electronics control (not shown).There are six chamber stages in which the 55C incoming hydrogen goes down the first chamber, and up the second chamber, and down the third chamber, and up the fourth chamber, and down the fifth chamber, and up the sixth chamber to the output port.The heat pipe is designed to minimize size and also to use a higher flow rate with the option of many vaporizable liquids that can be used - see slides a the end of the presentation. The choice of the liquid can be custom tailored to the rate of heat transferred and the flow of the liquid/vapors. Each stage performs successive cooling such that the incoming gas has condensed water at each stage thereby maximizing water extraction and reducing secondary processes.The fans are attached to a heat transfer plate designed of simple aluminum sheet metal with a very thin veneer of thermal adhesive and is attached via nylon screws. There is cardboard thermal isolation material to keep the heat pipe isolated from the condensation chamber. The plate is thermally isolated with an air-gap from the condensing chamber using cardboard washers, and thermally isolated from the top plate with another cardboard isolator on top. There are (3) commercially available high flow, high efficient heat sinks attached with thermal compound/adhesive. The fans are screwed into the threaded holes of the heat plate ensuring good compression of the heat sinks to the heat plate.Inside each chamber there is a corrugated copper foil curtain that is soldered to the heat pipe that uses 21 square cm of area x 2 sides x 6 = 252 sq cm of surface area that the hydrogen flows across.Water that condenses will drip down the copper curtains in each chamber and onto a specially designed droplet porous baffle. The baffle uses water meniscus surface tension to create a one-way valve ensuring the hydrogen flows thru each condensing chamber and not across the water collector. The collected droplets gravitate into the bottom water collecting pan and draining into an outlet fitting on the bottom. Each copper curtain is sealed into each chamber by epoxy after being soldered onto the heat pipe itself sealing each chamber from the heat pipe. Since the top plate is not only used to seal the chambers, it is also used to hold the heat pipe and may be best using a thermally insulating material such as a plastic, but plastics are typically not eco-friendly. The top plate is also the most complex part and may be cost prohibitive, so an injection molded part may be the most economical solution for it. Other parts may be aluminum for eco-friendliness and require much less machining.All fitting blocks on the condensing chamber and the bottom water collection plate have been oversized to accommodate at least 1/4" tube fittings and up to 1/2 tube fittings. Increasing port input-output size may reduce input pressure and slow down the flow rate which will help the water condensing transfer process onto the collecting copper curtains.Almost all BOM parts can be made with eco-friendly materials :(4) machined aluminum (eco-friendly) or plastic molded / injection parts (NOT eco-friendly)(1) custom closed-loop heat pipe CLHP (eco-friendly)(2) cardboard thermal isolators (eco-friendly)(3) COTS heat sinks (eco-friendly)(3) COTS fans with tachometers (WEEE recyclable)(6) Copper Foil 'Curtains' (eco-friendly)as required solder (RoHS) and chamber sealing epoxy (RoHS)flat head and socket cap screws (eco-friendly)