Study comparing the tribological behavior of propylene glycol and water dispersed with graphene nanopowder

Abstract

Nanofluids made up of propylene glycol, and water and graphene nanopowder dispersed throughout them are the primary focus of our study. Nanofluids were created by mixing propylene glycol and water in quantities of 100:0, 75:25, and 50:50. The essential fluids used in this experiment were propylene glycol and water. Graphene was dispersed in these three different base fluids at percentages of 0.25 and 0.5, respectively. This body of work's fundamental objective is to explore nanofluids' tribological behavior. This behavior was observed with a pin-on-disc device, and the impact for load on wear, coefficient of friction, and frictional force was investigated. The tests were conducted with weights ranging from 1 to 3 kg. It was revealed that as the load ascended, there was a reduction in the amount of wear, the coefficient of friction, and the frictional force for the most of the samples tested. Still, there was an increase in the amount of wear and friction coefficient, including the frictional force for some of the samples.

The relativity of reaching: Motion of the touched surface alters the trajectory of hand movements

“… 31 , 32 , 33 In two bare-fingertip conditions, the plate was lubricated either with ultrasound gel (resulting in a setting analogous to the one of the first experiment) or with seed oil, the latter having a higher friction coefficient than gel. 34 , 35 The ultrasound gel was also used as lubricant in the thimble condition. The experiment thus resulted in three conditions (labeled as gel , oil , and thimble ), each one tested in a separate block.…”

“…As measured in previous studies, the friction coefficient of ultrasound gel is lower than the one of seed oil. 34 , 35 Therefore, the use of different lubricants is expected to result in a modulation of shear forces during the reaching movement. Participants performed the reaching task similar to the first experiment, either with a rigid thimble covering their fingertip, or with their bare fingertip.…”

Evaluation of electrical properties of graphene nanopowder-dispersed propylene glycol-water solutions

“…In this experiment, samples of propylene glycol and water with three different proportions: 50:50, 75:25, and 100:0 are prepared [7]. With the assistance of such an ultrasonic probe sonicator, 0.25 and 0.5 weight percent of graphene nanoparticles are uniformly distributed throughout the intended solutions.…”

“…Another important factor is the size and distribution of nanoparticles within the propylene glycol-water solution [7]. Nanoparticles with smaller sizes and better dispersion tend to exhibit higher electrical conductivity due to enhanced particle-particle interactions and increased contact area with the fluid medium.…”

Response surface approach of Propylene Glycol and Water (75:25)/Graphene+MWCNT nanofluid viscosity

“…The largest spherical particle was 41 nanometers around, while the smallest was 34 nanometers [16]. Utilizing Response Surface Methodology (RSM), the current inquiry looks at the viscosity properties of a nano uid that is made up of Propylene Glycol-Water (75:25) and Graphene + MWCNT [20]. This investigation made use of four different models, and the accuracy and reliability of their output was evaluated with the use of charts and other metrical representations.…”