Clay Wesley Maranville

Bio: Clay Wesley Maranville is an academic researcher from Ford Motor Company. The author has contributed to research in topics: Electromagnetic coil & Electrical conductor. The author has an hindex of 14, co-authored 78 publications receiving 826 citations. Previous affiliations of Clay Wesley Maranville include Visteon.

TEG On-Vehicle Performance and Model Validation and What It Means for Further TEG Development

Abstract: A high-temperature thermoelectric generator (TEG) was recently integrated into two passenger vehicles: a BMW X6 and a Lincoln MKT. This effort was the culmination of a recently completed Department of Energy (DOE)-sponsored thermoelectric (TE) waste heat recovery program for vehicles (award #DE-FC26-04NT42279). During this 7-year program, several generations of thermoelectric generators were modeled, designed, built, and tested at the couple, engine, and full-device level, as well as being modeled and integrated at the vehicle level. In this paper, we summarize the history of the development efforts and results achieved during the project, which is a motivation for ongoing research in this field. Results are presented and discussed for bench, engine dynamometer, and on-vehicle tests conducted on the current-generation TEG. On the test bench, over 700 W of power was produced. Over 600 W was produced in on-vehicle tests. Both steady-state and transient models were validated against the measured performance of these TEGs. The success of this work has led to a follow-on DOE-sponsored TE waste heat recovery program for passenger vehicles focused on addressing key technical and business-related topics that are meant to enable TEGs to be considered as a viable automotive product in the future.

Thermal Conductivity of Single-Wall Carbon Nanotube Dispersions: Role of Interfacial Effects

Abstract: We report measurements of the effective thermal conductivity of dispersions of single-wall carbon nanotubes in technologically important fluids: (poly)-alpha olefins and ethylene glycol. The morphology of this dispersion was studied using rheology, AFM, and light scattering techniques. The enhancement of thermal conductivity was analyzed using a Maxwell−Garnett effective medium theory including the interfacial thermal-resistance layer between the nanotube and the fluid. The results were compared with previously reported results on multiwall carbon nanotubes in similar dispersion media and point to the critical role of the nanotube−fluid interfacial thermal resistance.

Control strategy for a zonal heating, ventilating, and air conditioning system of a vehicle

Abstract: A climate control system of a vehicle and a method of controlling the climate control system to minimize vehicle energy consumption and maximize occupant comfort. The climate control system includes a main HVAC system for conditioning a fluid discharged into a passenger compartment of the vehicle, an auxiliary HVAC system for conditioning a localized fluid of at least one HVAC zones of the passenger compartment, a seat system, and an HVAC controller. The HVAC controller controls the main HVAC system, the auxiliary HVAC system, and the seat system based upon at least one parameter and condition which pertains to at least one of electrical energy consumption of the vehicle and occupant comfort.

Airborne transmission of COVID-19 and mitigation using box fan air cleaners in a poorly ventilated classroom

Abstract: Many indoor places, including aged classrooms and offices, prisons, homeless shelters, etc., are poorly ventilated but resource-limited to afford expensive ventilation upgrades or commercial air purification systems, raising concerns on the safety of opening activities in these places in the era of the COVID-19 pandemic. To address this challenge, using computational fluid dynamics, we conducted a systematic investigation of airborne transmission in a classroom equipped with a single horizontal unit ventilator (HUV) and evaluate the performance of a low-cost box fan air cleaner for risk mitigation. Our study shows that placing box fan air cleaners in the classroom results in a substantial reduction of airborne transmission risk across the entire space. The air cleaner can achieve optimal performance when placed near the asymptomatic patient. However, without knowing the location of the patient, the performance of the cleaner is optimal near the HUV with the air flowing downwards. In addition, we find that it is more efficient in reducing aerosol concentration and spread in the classroom by adding air cleaners in comparison with raising the flow rate of HUV alone. The number and placement of air cleaners need to be adjusted to maintain their efficacy for larger classrooms and to account for the thermal gradient associated with a human thermal plume and hot ventilation air during cold seasons. Overall, our study shows that box fan air cleaners can serve as an effective low-cost alternative for mitigating airborne transmission risks in poorly ventilated spaces.

Investigation of thermal conductivity and rheological properties of nanofluids containing graphene nanoplatelets

Abstract: In the present study, stable homogeneous graphene nanoplatelet (GNP) nanofluids were prepared without any surfactant by high-power ultrasonic (probe) dispersion of GNPs in distilled water. The concentrations of nanofluids were maintained at 0.025, 0.05, 0.075, and 0.1 wt.% for three different specific surface areas of 300, 500, and 750 m2/g. Transmission electron microscopy image shows that the suspensions are homogeneous and most of the materials have been well dispersed. The stability of nanofluid was investigated using a UV-visible spectrophotometer in a time span of 600 h, and zeta potential after dispersion had been investigated to elucidate its role on dispersion characteristics. The rheological properties of GNP nanofluids approach Newtonian and non-Newtonian behaviors where viscosity decreases linearly with the rise of temperature. The thermal conductivity results show that the dispersed nanoparticles can always enhance the thermal conductivity of the base fluid, and the highest enhancement was obtained to be 27.64% in the concentration of 0.1 wt.% of GNPs with a specific surface area of 750 m2/g. Electrical conductivity of the GNP nanofluids shows a significant enhancement by dispersion of GNPs in distilled water. This novel type of nanofluids shows outstanding potential for replacements as advanced heat transfer fluids in medium temperature applications including solar collectors and heat exchanger systems.