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Annular regenerator screen stack, Ø48 / Ø42 × 40 (50 mesh × 0.22 mm wire)

Name: Annular regenerator screen stack, Ø48 / Ø42 × 40 (50 mesh × 0.22 mm wire) dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

How big should the regenerator screen stack be in a 2 in Stirling engine? · Hardware · basis: Porosity of stacked square-weave screens 1 − π m d / 4; friction and heat transfer from the Urieli & Berchowitz screen correlations

Long Earth Society build part. The regenerator of my performance engines. The engines

Exact dimensions. Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part. Mating features

sizes: 4 in table

Notes

Annular screens punched Ø48.00 outside, Ø42.00 inside, stacked 40 mm deep on the liner's neck: about 91 screens of 50 mesh (per inch) × 0.22 mm wire, porosity 0.660, hydraulic diameter 0.43 mm.
Gas volume in the stack 11.2 mL. In the cycle model its effectiveness is 0.966 on charged air at 600 rpm and 0.980 on helium at 1200 rpm.
Finer screens raise the effectiveness and the pumping loss together; I swept 0.10 to 0.30 mm wire and 0.22 mm was the best shaft power on air and on helium.

Sizes

item	value
envelope	Ø48.00 / Ø42.00 × 40
screen	50 mesh × 0.22 wire
count	≈ 91
porosity	0.66

Mating features

Drawn at the exact size. Open press, slide, run and socket features by your process's clearance; leave designed gaps and clamp fits as drawn.

feature	exact	mates with	fit	files
outside	Ø48.00	hot-spool finished bore	slide	all
inside	Ø42.00	liner neck	slide	all

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Ohio University (I. Urieli)	Stirling cycle machine analysis (after Urieli & Berchowitz, Stirling Cycle Engine Analysis, 1984): Schmidt and simple analyses, wire-screen regenerator friction fr = 54 + 1.43 Re^0.78 and St = 0.46 Re^−0.4 / Pr	web	university course pages verify
NASA (W. R. Martini)	Stirling Engine Design Manual, 2nd edition, NASA CR-168088 (1983): decoupled second-order losses (shuttle, conduction, flow friction, regenerator)	PDF	US government report
Cambridge University Press (J. R. Senft)	Mechanical Efficiency of Heat Engines (2007): shaft work = E·W − (1/E − E)·W_forced	book	book; formula cited verify
Long Earth Society	Engine builds	web, video	LES site