Shohel Mahmud

Instrumentation and Capabilities

• Thermal conductivity meter (TPS and KD2Pro): thermal conductivity measurement of material having conductivity less than 5 W/m/K
• Viscometer (rotary and vibration): dynamic viscosity measurement of liquid
• Densitimeter: liquid density measurement (T<45C)
• National Instrument DAQ systems for temperature measurement
• Constant temperature baths
• Sonicator
• Low temperature DSC
• Solid-liquid phase change visualization setup

Education and Employment Background

Dr. Shohel Mahmud received his PhD from the University of Waterloo in 2006. He went on to work as the Lead Researcher for the Thermal-Electromagnetic Analysis Group at the University of Waterloo, and as the Lead Researcher for the Thermal-Electromagnetic Analysis Group for Sprung-brett RDI in Amherst, New York. He joined the School of Engineering at the University of Guelph in 2010 where he is now a Professor and the Area Head for Mechanical Engineering.

Research Themes

Mahmud’s research is focused on the development of clean energy conversion technologies and devices. Key research themes include:

1. Novel Thermal Energy Storage System. Phase change materials (PCMs) exhibit excellent potential for various applications (e.g., energy storage, electronic cooling, and building energy management). However, PCMs’ low thermal conductivities slow down their melting/freezing rates. An effective method to improve the melting/freezing rates is to insert a porous medium inside any PCM system (e.g., energy storage). Mahmud is a pioneer in theoretical studies on phase change processes of nano-PCM inside a porous medium.
2. Thermoelectric (TE) Energy Conversion. Mahmud has performed analytical and numerical investigations to study the effect of nano-structuring on the performance of the thermoelectric power generator and cooler. In addition, Mahmud performed theoretical and experimental analyses of solar thermoelectric air-conditioning and liquid chiller systems. Such systems have promising applications in energy efficient building, electronic cooling, power generation for wearable electronic devices, and situations where electricity is in short supply.
3. Porous Stack Thermoacoustic System. Use of a porous stack in place of a traditional stack enhances the thermal contact area and improves the heat transfer rate between the fluctuating gas and nearby solid. Mahmud proposed the porous medium TAC theory (also known as ‘therporaoustic’ theory), a modification of the existing TAC theory, which treated the fluid-gaps within a stack of a TAC engine/refrigerator as porous medium, rather than simply as a multi-channel stack. 
4. Electromagnetic energy conversion: micro- to macro-power drives and control: Mahmud developed innovative Axial-Flux-Switched-Reluctance-Motor (AF-SRM), an eco-friendly clean technology, for In-Wheel Drive Vehicle (I-WDV) applications. AF-SRM can be scaled up or down and integrated into manipulators, rehabilitation devices, robotic grippers, and actuators. Our research results further confirm that developed AF-SRM has higher energy conversion efficiency, and can produce more torque/kg than other motors used for I-WDV applications. Three novel Fuzzy Control strategies were developed which increased torque density of AF-SRM using switching angles and optimal current profiles. Our work on T-shaped EMPG has already demonstrated the ability to improve the backup power supply for small scale electronic health monitoring and surveillance systems. The developed technologies and related knowledge are strategically important for surveillance device and vehicle industries.
5. Thermal Management of battery packs, electronic devices, and buildings: Mahmud developed a unique testing facility to investigate the effect of charge cycle, temperature, semi-active and passive battery thermal management system (BTMS) configurations on rechargeable electric vehicle (EV) batteries (e.g., Li-ion batteries) in the presence and absence of external vibration. Detailed tests on the functional prototypes (i.e., metal-foam-based-BTMS, TE-PCM-based-BTMS, and complex-fluid-based-BTMS) provide benchmark results for EV industries and researchers. Dr. Mahmud further developed analytical tools and experimental facilities to test range of environmentally friendly prototypes, e.g., PCM based fin-tube baseboard convector and active wall thermal energy storage system, for the thermal management of energy efficient building. Dr. Mahmud a closed loop Liquid-based-Thermoelectric-Electronic-Cooling (LTEEC) system which is self-adjustable to variable thermal load and can function as cooler or heater.

Highlights

• NSERC Discovery Grant, 2011, 2015
• NSERC Engage Grant, 2015, 2017
• Canada Foundation for Innovation, 2017
• Early Researcher Award, Ministry of Research and Innovation, Ontario, Canada, 2014

Media Coverage

Green Technologies

• U of G Engineering: Green Technology Offers Solutions for Developing Countries
• CEPS News: Renewable Heat for Buildings Worldwide