Comparison of the Efficiency of Two Types of Heat Exchangers with Parallel Plates Made of Varied Materials

The paper discusses two mathematical models for the air flow through a plate heat exchanger with parallel plates. The first exhausts the used air and then supplies the fresh air. The second exhausts the used air above the plate and simultaneously supplies fresh air under it (counter-flow exchanger). In both cases, the exhaust air heat is used to heat the supply air. The purpose of the research is to verify which exchanger uses the exhaust air heat more efficiently. The method of the Trefftz function was used to determine approximate solutions of the analysed problems. The results obtained for 1.2 mm thick steel, aluminium, and copper plates and for external winter, summer, and spring–autumn temperatures are discussed. The results indicate that steel is the best material for a plate heat exchanger, and the counter-flow exchanger is more efficient of the two. Thanks to the use of thin steel plates and the reduction of the air exchange time to a few minutes, cheap and efficient counter-flow exchangers can be obtained.

Analysis of Coconut Shell Concrete in the Sandwich Beam using ANSYS

SCS consists of a layer of unreinforced concrete core, sandwiched between two relatively thin steel plates with novel enhanced C-channel connectors. Compared to C-channel connectors, ECs directly link the two external steel faceplates. The cost of traditional materials used in the concrete is the major factor which increases the cost of constructions, so it is necessary to research for alternative construction materials. In this project, the concrete core is used as the coconut shell concrete. Coconut Shell is a waste, generated by industrial and agricultural processes, and has created disposal and management problems that pose serious issues of environmental pollution. The first objective is to analyze the composite properties at 0%, 10%, 20% and 30% of coconut shell in the sandwich beam using rules of mixture . The Rules of Mixture is an analytical equations that are used to calculate the composite properties of the material. Then analyze the effect of coconut shell sandwich beam in ANSYS software. Also compare the conventional sandwich beam and coconut shell sandwich beam. Analyze the strength and decaying of coconut shell sandwich beam using ANSYS.

Influence of Clamping for Out-of-Plane Welding Distortion Mitigation During Thin Steel Plates Welding

Thin steel plates is usually employed for lightweight application, while welding distortion in particular welding induced buckling, will significantly influence dimensional accuracy of thin-walled structure. As elementary investigation of out-of-plane welding distortion mitigation, butt and fillet welded joints with thin plates were experimentally conducted with considering clamping influence. Effective thermal elastic plastic FE computation was proposed to examine mechanical response caused by welding, and large deformation theory was applied to represent welding induced buckling. Good agreement between measured data and computed results can be observed. Furthermore, FE computation without clamping was also carried out to clarify the difference of plastic strains and residual stress comparing with experimental case. Influence of clamping on out-of-plane welding distortion mitigation was eventually proposed for mechanism understanding.