By Kim A. Stelson, CCEFP Director.

Three graduate student researchers were awarded prizes for "Best Poster" during the CCEFP Annual Meeting held March 22-23 at IFPE.  The judging panel was comprised of several CCEFP Industry member representatives and the CCEFP Scientific Advisory Board.  Points were awarded based on content, design, presentation skill and overall effectiveness, with prizes of $100, $250 and $500 awarded for 3rd, 2nd, and 1st places respectively. This was the first time that awards were given during the Center's annual poster show.

The winners were:

1ST PLACE:  $500

Graduate Student Presenter: Josh Zimmerman, Purdue University
Testbed 1: Heavy Mobile Equipment - High Efficiency Excavator
Faculty Advisor: Professor Monika Ivantysynova

Left:  Prof. Andrew Plummer, University of Bath, CCEFP Scientific Advisory Board
Right:  Josh Zimmerman, Ph.D. Student, Test Bed 1: Excavator, Purdue University

Poster Abstract: The excavator test bed serves as a platform for demonstrating research advances throughout the CCEFP.  It is a 5 ton Bobcat 435 excavator, but the stock hydraulic system (load sensing) has been removed and replaced with a displacement controlled hydraulic system.  Results for side by side fuel testing of the new displacement controlled hydraulic system and a standard machine of the same model found 40% fuel savings on average for a truck loading cycle and will be included in the poster presentation.  With the new system architecture all functions are controlled electronically allowing the use of advanced control strategies.  An advanced machine power management control strategy has been implemented on top of the displacement control platform to minimize the fuel consumption of the machine according the working cycle performed.  Simulated and measured results for this control algorithm will be presented.  The improved efficiency offered by displacement controlled technology has led to lower working temperature for the hydraulic fluid.  A thermal model of the hydraulic system has been developed to simulate working temperatures and to aid in specifying the cooling requirements for the new hydraulic system.  Finally, a feasibility study for a hybrid displacement controlled hydraulic system, allowing energy recovery and engine load leveling, will also be presented.

2ND PLACE: $250

Graduate Student Presenter: John Tucker, Vanderbilt University
Project 2C.2: Advanced Strain Energy Accumulator
Faculty Advisor: Professor Eric Barth

Poster Abstract:  Hydraulic accumulators are energy storage devices commonly used to provide supplementary fluid power and absorb shock. One particularly interesting recent application of these devices is regenerative braking in hybrid vehicles. The purpose of this research is to investigate a new method of storing energy particularly suited for use in Hydraulic Regenerative Braking (HRB). Specifically, this project’s objective is to design a low cost, minimal maintenance, high energy density accumulator for implementation in a fluid powered automotive regenerative braking system in a hydraulic hybrid vehicle. The advocated technique involves using strain as the mechanism for energy storage, as opposed to the compression of gas in typical gas-charged accumulators. However, by using a high energy density elastomer and a geometry that differs from conventional spring-piston accumulators, the proposed accumulator addresses some of the weaknesses of its traditional counterparts.

3RD PLACE: $100

Graduate Student Presenter: Kelly Burgess, Milwaukee School of Engineering
Project 1G.1: Tribofilm Structure and Chemistry in Hydraulic Motors
Advisor: Paul Michael, Research Chemist

Poster Abstract: This poster presents an investigation of the fluid properties that affect starting efficiency in hydraulic motors. Starting motor efficiency is an important design consideration because it often determines the pump horsepower and the minimum motor displacement in mobile hydraulic systems.  Five hydraulic fluids have been tested and evaluated in a large-scale hydraulic dynamometer.  The boundary friction, mixed-film lubrication, thermophysical, and pressure-viscosity properties of these prototype fluids have been characterized. These hydraulic fluids have been evaluated in geroler, axial piston, and radial piston motors under starting conditions in accordance with the ISO 4329-2 standard test method.  Correlations between starting efficiency and fluid boundary friction, traction,thermophysical and pressure-viscosity coefficients have been identified.  The results indicate that startability improves with decreasing boundary friction coefficient, decreasing pressure-viscosity coefficient, and increasing thermal conductivity. The relative impact of these fluid properties varied with motor design.

Congratulations to the three winners and to all the students who produced very high quality posters for this year's show!