Miniature Ringbom Engines

By James Senft                          

List Price  $17.95

Ringbom Stirling Engines

By James Senft      

List Price $44.95       

Miniature Ringbom Engines is a practical introduction to a whole new branch of Stirling engine technology. The Ringbom engine is a hot air engine with a normal crank-coupled piston but with a displacer having no mechanical linkage. The free displacer is driven back and forth automatically by the changing pressure within the engine. This makes the Ringbom an utterly fascinating engine to see in operation and opens up a wide new world of possible configurations for engine designs. This first ever book on miniature Ringbom engines is primarily a how-to book, focused on presenting all the information needed for making good working model engines. Detailed plans and instructions for making three different types of Ringbom models are at the heart of the book. These comprise a tiny engine that runs at high speed on a small alcohol flame, a larger low temperature differential Ringbom which can run for hours on the thermal energy in a few cups of hot water, and an advanced single-cylinder Ringbom engine. The book starts by clearly explaining the basic principles behind Ringbom engine operation, and concludes with a chapter containing a large collection of new engine designs and ideas to explore. The author, Prof. James Senft pioneered the mathematical analysis and development of the modern form of the Ringbom engine.

Ringbom Stirling Engines provides a highly technical treatment of the entire field of Ringbom free displacer engines from the simple to the advanced and from small to large. First published in 1993 by Oxford University Press, it has been newly reprinted in its complete original high quality clothbound form. The book contains a lengthy introductory chapter covering the development of all types of Stirling engines with special emphasis on the mechanism problem. The second chapter describes the original Ringbom patent and its recent simple modification which transformed it into an engine capable of high speeds and rock-stable operation. For the mathematically inclined, following chapters develop formulas for calculating the stable operating range, phase angle, and power output of Ringboms. The book shows how to use this foundation to design Ringboms to run on low or high temperature differentials and concludes with a chapter on engine ideas for further exploration. The book is well illustrated and contains material not readily available elsewhere.

A Heat Engineer or Hobbyist Dream.