Background

This invention is a new thermal buoyancy engine used in underwater gliders. This engine uses phase changing material to create a volume change using the changing temperature in the ocean, so that to produce a buoyancy change to drive the gliders. However, the current thermal buoyancy engine is limited by its capacity. But because the need of buoyancy change is not so significant for the current underwater glider, there is no great need to develop a large capacity thermal buoyancy engine.

Whereas in Strathclyde, the researchers are aiming to develop a self-sustainable underwater glider which can harvest the kinetic energy by diving and surfacing, where the power output is directly related to the buoyancy change capacity. Therefore, the need of large capacity thermal buoyancy engine is urgent and not available off-the-shelf.

Technology Overview

This invention is a new type of thermal buoyancy engine enhanced by using a single-acting cylinder in addition to a double-acting cylinder to amplify the buoyancy change capacity for self-sustainable underwater gliders (). With the same amount of Phase Changing Material (PCM), the new buoyancy engine equipped with the buoyancy amplifier can amplify the buoyancy change, therefore to increase the electricity output to sustain the glider operation. The new thermal buoyancy engine will also enhance underwater gliders’ performance, by improving the gliding speed and enhancing the survivability and the endurance.

The research team in the University of Strathclyde develops the technology by aiming to use their expertise in the marine hydrodynamics and develop the cutting-edge applicable biomimetic technologies to enhance the performance of marine devices. The mission of the research group is to understand the need for development in marine industry so that to get inspired from the Mother Nature and to develop technology to address the challenges.

Benefits

Solve the problems of the traditional thermal buoyancy engine
- Increase the payload capacity of existing AUV.
- Improve the environment adaptability of existing underwater glider.
- Enhance the gliding speed so that to enhance the operation efficiency.
Make a new type power generation system feasible and increase the voyage
- A new type power generation unit and gliding strategy developed.
- This power generation system is more reliable because most of the units are not working in high pressure.
- The rotor can be used both as a propeller to propel the underwater glider and as a turbine to harvest the kinetic energy.
- The power output estimation of the power generation unit.

After applying the new type thermal engine, the preliminary math model shows without increasing the mass requirement of PCM the power output peaks at 20+w in the power generation mode.

A New Type of Thermal Buoyancy Engine and its Control Method

Patents

IP Status

Seeking