{'fraction_non_alphanumeric': 0.016034985422740525, 'fraction_numerical': 0.0029154518950437317, 'mean_word_length': 5.420560747663552, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Internally Enhanced Carbon Steel Tubes for Ammonia Chillers

Experimental data were obtained with two different commercially available, internally enhanced carbon steel tubes using glycol mixtures as the tube-side fluids. In the turbulent regime, these data show that enhancement levels of 2.5 or greater are possible and that the pressure-drop increase is about the same as or slightly less in magnitude than the heat transfer enhancement. However, these enhanced tubes are currently not recommended for most laminar-flow applications because of erratic behavior believed to be related to the wandering laminar?turbulent transition and of limited or no enhancement for some conditions.