4958681 Heat exchanger with bypass channel louvered fins

New Patents changer comprises a generally planar panel having a pair of relatively thin unitary outer walls formed from a composition of a thermoplastic polymer, expecially a polyamide. The walls, which have a thickness of less than 0.7 mm, are bonded together to form a labryinth of fluid passages between the walls. The passages extend between inlet and outlet means and occupy a substantial proportion of the area of the panel. The heat exchangers are relatively economical to manufacture and may be used in a variety of end uses, depending on the properties of the polymer composition, including in some instances as heat exchangers in automobiles.

ix

A process for the generation of mechanical energy in the ammonia oxidation step of process for the production of nitric acid is disclosed, whereby the utilization of process heat is improved, particularly the exploitation of heat conrained in NOx gases and including process heat recovered at low temperature. The process involves evaporating and superheating liquid ammonia upstream of the oxidation step, at a pressure which is a multiple of the pressure required for the combustion, using the process heat of the NOx gases formed during the the combustion and then expanding the superheated ammonia in a turbine, thus generating mechanical energy.

4956977 ADSORPTION APPARATUS USED AS AN ELECTRO-HEATING STORAGE Pete Maier-Laxhuber, Fritz Kaubek, D 8000 Munchen 60, Federal Republic Of Germany Periodic adsorption apparatus with the substance pair zeolite/water being used as electroheat storage devices. Due to the heat pumping effect there can be a 30% savings of power. 4957159 ALUMINUM HEAT EXCHANGER PROVIDED WITH FINS HAVING HYDROPHILIC COATING Masaaki Mizoguchi, Susumu Inoue, Tatsuo Otsuka, Eizo Isoyama, Sakai, Japan assigned to Showa Aluminum Corporation The fins of an aluminum heat exchanger are treated with a coating composition comprising an alkali silicate, an inorganic hardening agent and a water-soluble organic high-molecularweight compound, whereby a hydrophilic coating is formed over the surfaces of the fins. 4957720 PROCESS FOR THE GENERATION OF MECHANICAL ENERGY IN THE AMMONIA OXIDATION STEP OF A NITRIC ACID PRODUCTION PROCESS Karl W Wiegand, Michae Thiemann, Erich Scheibler, Dortmund, Federal Republic Of Germany assigned to UHDE GmbH

4958681 HEAT EXCHANGER WITH BYPASS CHANNEL LOUVERED FINS Durgaprasad S Kadle assigned to General Motors Corporation Louvered fins in fin and tube type heat exchangers extend across the spaces between adjacent tubes. Adjacent tubes are separated by a distance s and louvers in the fins extend between the tubes but stop short of the tubes to leave some plain fin area which defines a bypass channel of width b between each tube and adjacent louvers. The curve of heat transfer versus air side pressure drop increases as the ratio b/s decreases. An optimum value of b/s occurs at the knee of the curve and lower values of the ratio effect insignificant improvements in heat transfer. 4959526 STORAGE TYPE ELECTRIC WATER HEATER HAVING A CLOSED CIRCULATION LOOP WITH A BUBBLE PUMP Yasuhiko Kurachi, Kazumi Mori, Hisao Koizumi, Aichi, Japan assigned to Chubu Electric Power Company Inc; Kabushiki Kaisha Toshi A hot water boiling apparatus includes a hot water tank filled with water. A water supply pipe and a hot water supply pipe are connected to the bottom and top of the tank, respectively. A bubble pump unit is arranged in parallel with the tank. The pump unit includes a body having a