Gene Markey

An unattractive man whospent much of his early career writing B-movie screenplays, Gene Markey possessed enough charm and wit to convince actresses Joan Bennett, Hedy Lamarr, and Myrna Loy to take a walk down the aisle with him while they were at the height of their careers. None of these marriages lasted more than a few years, however. Markey had raised his ante as a successful producer at 20th Century Fox by the time he married his fourth wife: Lucille Parker Wright, the widowed owner of America’s most powerful racing stable, Calumet Farm. The Markeys won three Kentucky Derbies with Iron Liege, Tim Tam, and Forward Pass before mismanagement drove Calumet into a downward spiral from which it never recovered, signaling the end of the Golden Age of horse racing in America.

Starting from Scratch

Proceeding with working groups, the amalgamated rules committee’s open-play working group (Camp, E. K. Hall of Dartmouth, Reid) rejects forward passing across the scrimmage line. But at the next full rules-committee meeting, Hall individually proposes passing across the line under certain limits—for example, loss of possession if the passed ball strikes the ground, untouched by a player. His proposal becomes the basis for full committee approval of forward passing along with Camp’s ten-yard rule (plus a neutral zone separating opposing lines). A Central Board of Officials is also created, with Camp a member, to instruct officials, develop a roster of satisfactory officials, and on request appoint officials for games. St. Louis University, coached by Edward Cochems, uses forward passes extensively in 1906. Cochems writes an article on passing for Camp’s How to Play Football booklet. Camp successfully uses a pass against Harvard in 1906 for the winning points. By 1908 a number of Midwest teams are using the forward pass ten or more times per game.

Reverse-Pass Cooling Systems for Improved Performance

Total heat transfer between a hot and a cold stream of gas across a nonporous conductive wall is greatest when the two streams flow in opposite directions. This counter-current arrangement outperforms the co-current arrangement because the mean driving temperature difference is larger. This simple concept, whilst familiar in the heat exchanger community, has received no discussion in papers concerned with cooling of hot-section gas turbine components (e.g., turbine vanes/blades, combustor liners, afterburners). This is evidenced by the fact that there are numerous operational systems which would be significantly improved by the application of “reverse-pass” cooling. That is, internal coolant flowing substantially in the opposite direction to the mainstream flow. A reverse-pass system differs from a counter-current system in that the cold fluid is also used for film cooling. Such systems can be realized when normal engine design constraints are taken into account. In this paper, the thermal performance of reverse-pass arrangements is assessed using bespoke 2D numerical conjugate heat transfer models, and compared to baseline forward-pass and adiabatic arrangements. It is shown that for a modularized reverse-pass arrangement implemented in a flat plate, significantly less coolant is required to maintain metal temperatures below a specified limit than for the corresponding forward-pass system. The geometry is applicable to combustor liners and afterburners. Characteristically, reverse-pass systems have the benefit of reducing lateral temperature gradients in the wall. The concept is demonstrated by modeling the pressure and suction surfaces of a typical nozzle guide vane with both internal and film cooling. For the same cooling mass flow rate, the reverse-pass system is shown to reduce the peak temperature on the suction side (SS) and reduce lateral temperature gradients on both SS and pressure side (PS). The purpose of this paper is to demonstrate that by introducing concepts familiar in the heat exchanger community, engine hot-section cooling efficiency can be improved whilst respecting conventional manufacturing constraints.

Reverse-Pass Cooling Systems for Improved Performance

Total heat transfer between a hot and a cold stream of gas across a non-porous conductive wall is greatest when the two streams flow in opposite directions. This counter-current arrangement outperforms the co-current arrangement because the mean driving temperature difference is larger. This simple concept, whilst familiar in the heat exchanger community, has received no discussion in papers concerned with cooling of hot-section gas turbine components (e.g. turbine vanes/blades, combustor liners, afterburners). This is evidenced by the fact that there are numerous operational systems which would be significantly improved by the application of ‘reverse-pass’ cooling. That is, internal coolant flowing substantially in the opposite direction to the mainstream flow. A reverse-pass system differs from a counter-current system in that the cold fluid is also used for film cooling. Such systems can be realised when normal engine design constraints are taken into account. In this paper, the thermal performance of reverse-pass arrangements is assessed using bespoke 2D numerical conjugate heat transfer models, and compared to baseline forward-pass and adiabatic arrangements. It is shown that for a modularised reverse-pass arrangement implemented in a flat plate, significantly less coolant is required to maintain metal temperatures below a specified limit than for the corresponding forward-pass system. The geometry is applicable to combustor liners and afterburners. Characteristically, reverse-pass systems have the benefit of reducing lateral temperature gradients in the wall. The concept is demonstrated by modelling the pressure and suction surfaces of a typical nozzle guide vane with both internal and film cooling. For the same cooling mass flow rate, the reverse-pass system is shown to reduce the peak temperature on the suction side and reduce lateral temperature gradients on both suction and pressure sides. The purpose of this paper is to demonstrate that by introducing concepts familiar in the heat exchanger community, engine hot-section cooling efficiency can be improved whilst respecting conventional manufacturing constraints.