TORONTO — Yep, it’s back. Sort of.

Once upon a time, a Kenworth gas turbine-powered cabover sat forlornly in the background at the Eaton proving grounds in Marshall, Mich — evidence of a technology that once looked good but didn’t make the cut.

Reportedly, it sucked fuel like a turbo sucks air, so it was abandoned.

Recently, though, a Florida company called Turbine Truck Engines has declared plans to build what it calls a Detonation Cycle Gas Turbine (DCGT) engine for use in heavy trucks in North America and elsewhere. And they have a joint-venture agreement with a Chinese company called Beijing Royal Aerospace Facilities to develop and build it.

The joint venture is now working out the details for the design and construction of the next-generation prototype of this motor, which will use natural gas as its fuel source and will be manufactured in China. They figure they’ll have an engine built and ready to test by June, 2011.

The Florida folks say the engine can actually use any fuel that can be gasified (gasoline, diesel, propane, natural gas, hydrogen, methanol, ethanol or LPG) or a fuel mixture of some sort, yet needs little or no coolant, lube oil, filters, or pumps.

"Its unique, lightweight turbine design has few moving parts, significantly reducing maintenance costs. The innovative cyclic detonation process produces a near-complete combustion of fuel-oxidizer mixtures, resulting in greater fuel economy and fewer harmful exhaust emissions," says TTE.

Here’s the company’s explanation of the power-making process:

"A DCGT engine includes a turbine rotor contained within a housing. Exhaust ports of respective valveless combustion chambers located on opposite sides of the rotor direct combustion gasses towards the turbine, which operates in similar fashion to a Pelton water wheel."

[A Pelton wheel, simply enough, is a turbine that harnesses the momentum of rushing water rather than its weight. It’s the most efficient water turbine as a result.]

"Turbine blades are positively displaced through a blade race (tangentially to the turbine shaft) by kinetic impact and expansion of gases exiting from the combustion chambers via nozzles, rather than pistons, axial flow, or radial inflow expanders.

"The combustion chambers are connected by a valveless manifold fed with fuel and oxidizer.

"When combustible gases are detonated by an igniter in one of the combustion chambers, the back pressure from the detonation shuts off the fuel and oxidizer flow to that chamber and redirects the fuel and oxidizer to the opposite chamber, where detonation occurs. The process repeats cyclically. Power is taken off the rotor shaft mechanically or electrically."

More power to them, if you’ll pardon the expression.

— Rolf Lockwood