Precision in heating chemical solutions has become increasingly problematic. The variance in temperatures over time, or through the material of modern screening plates, creates error in researchers’ work. Chemical reactions occur at different temperatures and if a researcher is not able to maintain the desired temperature over time, or evenly heat the solution to the specific temperature, the reaction they aimed to create would not be successful.
To solve this problem, Conductive Solutions has paired with Click Bio, a local start-up company which specializes in labware. Conductive Solutions plans to alter the geometry of a traditional screening plate in order to optimize the heat transfer within each well of the plate. A design constraint comes from the SLAS Standards for industry screening plates. The footprint of the design must match these standards. In order to quickly reach the consumers’ desired temperature, Conductive Solutions will choose a thermally conductive polymer which is chemically compatible with common lab solutions, and can withstand the ramp temperatures researchers’ commonly use.
Proof of Concept
Conductive solutions is mainly using SolidWorks to complete the testing on the thermally conductive screening plate. The team has their model complete in SolidWorks, but have to get information back from the material company before they can start running simulations. The materials have been selected and the team ordered some samples to run tests in the lab. The team will gather data on the heat transfer as the materials chemical compatibility. They will use a thermocouple probe and data acquisition setup to measure the temperatures at various locations on the sample. They will take the data from the in person testing and the SolidWorks simulations and compare the two in order to make a final decision on a material. Thus far, the team has contacted the material companies to get the information needed as well as samples. Until those come in, there aren’t any tests the teams can run.
Conductive Solutions aims to solve a thermal issue with the widely-used screening plates in laboratories. In traditional designs, individual wells have inconsistent heat transfer throughout the plate which creates an issue because the solution in the wells is not heated evenly. Along the same line, the inner wells do not reach the same maximum temperature as the wells located on the perimeter of the plate. Conductive Solutions’ is designing a plate which complies with ANSI and SLAS standards, while being thermally innovative in the custom labware market.
Conductive Solutions has tested numerous materials against thermal and chemical criteria to inform the team of a single material which will increase the heat transfer in the wells. To further improve the plates, the team is incorporating traditional methods of improved heat transfer via geometric optimization. The new wells have a drafted octagon shape, Fig. 1 and 2, to allow mixability, while increasing the amount of solution touching the conductive material, ensuring a more even heat distribution in the solution. The draft will allow users in input a heat source evenly throughout the plate. A conical shape at the bottom of each well ensures the solution will collect at the lowest, center point of the well enabling the user to extract the solution in its entirety. Incorporating both methods into a single design has allowed the team to effectively increase the quality of experiments conducted with the plate.
By designing a single well to fit within the industry’s automation standard for footprint dimensions, Conductive Solutions is enabling their sponsor, Click Bio, to produce customized screening plates for their customers at a faster rate. The increase in quality of results and the speed at which the plates will be produced will be invaluable to consumers. These combined geometric, material, and the chemical compatibility improvements offered by Conductive Solutions’ screening plate will set it apart from traditional plates.
Conductive Solution’s main concern when redesigning the screening plate was to increase the rate heat transfer while maintaining uniformity. With this in mind, the fabrication process of the new plate is very similar to that of the original screening plates. A mold of the plate will be made in order to injection mold plates out of the new material. This process can be repeated for thousands of plates using the same original mold. Once the plates come out of the injection molder, they will be inspected, sanitized, and packaged for shipping. The mold will be created out of a 3D model of the newly designed screening plate through the program SolidWorks.
Figure 1: This detailed image for the injection molding device helps a user visualize and understand the injection molding process.
Figure 2: This is an example image for a mold, where the material will be injected at a high temperature to create the screening plates.
Testing and Results
Conductive Solutions’ primary test plan was to use Solidworks to conduct thermal analysis of various models. Primarily, single well testing was performed. Since the screening plate models use a repeating geometry, the data from single well tests can be extrapolated to an entire plate. Simulations were conducted using a variety of temperature and heat flux conditions to account for different scenarios. Graphs were created showing the temperature change of the slowest responding sections within the well. For comparison, Figure 1 shows the temperature change of the well for which Conductive Solutions was attempting to improve upon. Figure 2 shows the temperature response of Conductive Solutions’ optimized well. Figure 3 shows the temperature response of Conductive Solutions’ optimized well utilizing a special material. FInal testing was done through simulations because the team was unable to create a finished physical prototype due to the cost of injection molding the plate.
Figure 1: Thermal response of cylinder well. Steady state time of 542 seconds.
Figure 2: Thermal response of engineered octagon well. Steady state time of 481 seconds. Just through geometry changes, the time to thermal equilibrium was reduced by about 61 seconds, a 11% reduction.
Figure 3: Thermal response of octagon well using special well material. The steady state time is 30 seconds. Operating temperature was reached 94% faster when compared to the cylinder well made of polypropylene.
Overall, the optimized screening plate does what it was designed to do: Each well has even interior heating, creating a stable environment for any experiment being performed; It is able to be heated and cooled multiple times without warping; And heat effectively transfers to each well.
With this final design, Conductive Solutions has solved the problem it sought to address. Science laboratory experiment time, utilizing heated and cooled screening plates, will be reduced. This increase in lab efficiency will save time and money for the user.
Meet the Team
Lexey is a senior Mechanical Engineering student at the University of Nevada, Reno. Lexey was born and raised in Reno, and decided to pursue Mechanical Engineering due to her prior experience racing motorcycles, and working in her dad’s shop. Lexey has a published paper from research she completed at Los Alamos National Lab and plans to return to Los Alamos in the summers after graduating in May 2017. She will be completing a Master’s in Business Administration in during the Fall and Spring of the year following graduation.
Cameron is a senior student pursuing a degree in Mechanical Engineering at the University of Nevada, Reno. He grew up within an hour from Reno in Dayton, Nevada. Cameron has worked since he was able to get his workers permit at the age of 14 in various customer service fields. He excelled in math and science studies and decided to take it to the next step to pursue engineering. He enjoys hands-on learning and being outdoors. Cameron will be graduating in Spring 2017 with a degree in Mechanical Engineering as well as a minor in renewable energies.
Blair is a senior at the University of Nevada, Reno studying Mechanical Engineering. She is from Rocklin, California originally and moved to Reno in 2013 to pursue her degree. Starting in the Pre-Nursing program at UNR she changed her major to Mechanical Engineering in January of 2015. The Pre-Nursing background has helped Blair decide that upon graduation she wants to go into the Biomedical engineering field and do cancer research. She graduates in December 2017 and plans to travel before going into the field.
Jacob is a senior at the University of Nevada, Reno. He is earning a Bachelor of Science in Mechanical Engineering degree with an Electrical Engineering, Minor. He earned an Associate of Science degree from Western Nevada College. Jacob was born in Ojai, California, and has lived in Nevada since 2001. After graduation in May 2017, Jacob intends to enter the private job sector doing design work for mechanical systems.
Ryan is a senior Mechanical Engineering student at the University of Nevada, Reno. He grew up in Rocklin, California and attended Del Oro High School in Loomis. After graduating in 2013 he enrolled in the College of Engineering at the University of Nevada. Along with focusing on engineering, he also captains the University’s Men’s Ultimate Frisbee Team. After graduating in the Spring of 2017, he is on track to complete his Master’s in Business Administration in one additional year here at the University of Nevada, Reno.
Conductive Solutions would like to formally thank Click Bio and the capstone professors for their support throughout the year.