PRV Performance, Golden, Colorado, is developing PRV induction, Pintle-Regulated Venturi fuel Induction system which replaces the intake manifold on an engine and provides throttling, fuel injection and homogeneous mixing of the air and fuel at each cylinder. The system has demonstrated fuel efficiency improvements of 14% to 25%, torque and horsepower increases, and significant reduction of emissions.
PRV works as follows:
- Air enters the contoured Venturi via an air filter.
- Fuel vaporizes and expands in the low pressure throat.
- Fuel vaporization induces air flow into the Venturi entrance.
- Fuel vaporization in confined space thrusts mixed charge into the engine.
- Charge is always homogeneously mixed and cooled because the pintle regulates air flow at the confluence of fuel and air.
PRV describes the process as follows: PRV induction, with fuel injection directly at the Venturi throat, effectively mixes fuel and air due to the high velocity and reduced pressure at the vapor-liquid contact region, while pressure is recovered in the expansion section. Fuel vaporization in the confined Venturi volume amplifies air flow into the PRV entrance.
Characteristics and Benefits of PRV Induction:
- Fuel economy is dramatically improved. Fuel is vaporized and thoroughly mixed with air even at low throttle.
- Dynamometer tests prove torque and horsepower are substantially increased, even at low rpm.
- Green house gas emissions are reduced. Independent emission testing by Air Care Colorado demonstrated a substantial reduction in vehicle emissions for CO, CO2 and NOx.
- PRV cost is comparable to a conventional manifold/throttle body induction system.
Eight generations of prototypes have been installed and tested in a 1993 Honda Civic revamped with a JDM D15B single overhead cam engine. Prototype number 8 is currently undergoing tuning and testing.
Results of dynamometer testing on the 1993 Honda Civic, showing the improvement in horsepower (top curves) and torque (bottom curves), are shown in the graph to the left (click to enlarge). The stock JDM D15B single overhead cam engine results are shown in red and the PRV system in blue.
A prototype vehicle incorporating a PRV system is available for you to drive according to this page on the website.
U.S. Patent 6,868,830 introduces the concept of a Pintle-regulated Venturi (PRV) for premixing mixing fuel and air at all throttle settings for an internal combustion engine (ICE).
This is but one of the many ideas to improve the performance of ICE engines that have been proposed over the years. Who knows which ones will succeed. I find it interesting to present some of these ideas to induce your comments. This one seems to me to have some merit in its conception, being a rather simple idea. The idea seems to center on producing a homogeneous mixture of air and fuel just prior to entering each cylinder. Using a pintle to throttle the air at each cylinder, in conjunction with the venturi and fuel injection, certainly improves the fluid dynamics of the process. The key is to whether the mixing at the venturi throat actually results in improved performance and better fuel economy that is sufficient to cause the automobile industry to change its model on fuel induction or whether it is cost effective enough to create an after market. Carefully controlled laboratory tests are not usually the same as can be obtained in the real world with drivers having widely varying driving habits.
All material used in this post, except my comments, are derived from material on their website.