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The Mercia Mudstone Group (MMG) crops out extensively across England and Wales and its thermal properties are required for the design of infrastructure such as ground source heating and cooling schemes and electrical cable conduits. Data from the literature and new data from a borehole core have been compiled to generate an updated range of thermal conductivities related to rock type and the lithostratigraphy. These indicate a total range in saturated vertical thermal conductivity of 1.67–3.24 W m−1 K−1, comprising 1.67–2.81 W m−1 K−1 for mudstones, 2.12–2.41 W m−1 K−1 for siltstones and 2.3–3.24 W m−1 K−1 for sandstones. These data are all from measurements on samples and there will be uncertainty when considering the thermal properties of the rock mass owing to micro- and macrostructural features. Geometric mean modelling of thermal conductivity based on mineralogy has overestimated the thermal conductivity. Correction factors for the modelled thermal conductivities have been calculated to allow a first estimate of MMG thermal conductivities when only mineralogical data are available. Measured thermal diffusivities from the borehole core were in the range of 0.63–3.07 × 10−6 m2 s−1 and are the first measured thermal diffusivities to be reported for the MMG. [ABSTRACT FROM AUTHOR]

This research investigated the impact of different processing temperature (extrusion at 160°C and 180°C) and the influence of the TiO2 and CaCO3 fillers on morphology, mechanical, and thermal properties of polylactide (PLA) blended with low‐density polyethylene (PE‐LD) and high‐density polyethylene (PE‐HD) in 90/10 weight ratio. The impact of the particle size of the filler was also examined with the three types of TiO2 filler. It has been shown that the different processing temperature has no significant impact on the morphology, mechanical, and thermal properties of PLA/PE‐LD 90/10 and PLA/PE‐HD 90/10 polymer blends. It has also been shown that better phase interaction is not the crucial factor for the improvement of the mechanical properties but the domain size distribution of the dispersed phase within the matrix and the dispersion of the filler are. Samples with a narrow size distribution of the dispersed phase domain (5 to 10 μm) with the higher portion of larger domains that are uniformly distributed within the polymer matrix showed best mechanical properties. POLYM. ENG. SCI., 59:1395–1408 2019. © 2019 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Shallow alluvial aquifers have been overlooked as thermal resources for low-carbon cooling in the UK. Most existing groundwater cooling systems in central London, for instance, use the deeply confined Chalk aquifer. Potential over-exploitation of the Chalk aquifer as a heat sink was one of the primary reasons why the River Terrace Gravels aquifer was investigated at the Tate Modern. Other considerations included a higher likelihood of achieving the required groundwater yields and the ability of the shallow River Terrace Gravels aquifer to dissipate heat more effectively than the deeper, confined Chalk. Where net heat rejection is large, the extent to which waste heat can escape the system is critical to the long-term sustainability of the scheme. Factors influencing heat loss include the thickness of cap rock and the ratio of surface area to thermal volume. Cost of scheme development in the River Terrace Gravels was also an important consideration and projected long-term energy savings as a result of sourcing water from a shallower aquifer, with lower pumping lifts, were considerable. Although circumstances where the River Terrace Gravels may be utilized for heating and cooling are limited owing to the restricted area underlain by these deposits, the variable saturation and potential vulnerability of basements to leakage if affected by raised groundwater levels in the vicinity of recharge wells, they may be a viable alternative to the Chalk for some locations. Continued monitoring of the operation of the Tate Modern scheme will provide further evidence of the viability of schemes using the Thames Gravels. [ABSTRACT FROM AUTHOR]

With a changing climate, London is expected to experience more frequent periods of intense rainfall and tidal surges, leading to an increase in the risk of flooding. This paper describes the simulation of the drying of flooded building archetypes representative of the London building stock using the EnergyPlus-based hygrothermal tool ‘University College London-Heat and Moisture Transfer (UCL-HAMT)’ in order to determine the relative drying rates of different built forms and envelope designs. Three different internal drying scenarios, representative of conditions where no professional remediation equipment is used, are simulated. A mould model is used to predict the duration of mould growth risk following a flood on the internal surfaces of the different building types. Heating properties while keeping windows open dried dwellings fastest, while purpose built flats and buildings with insulated cavity walls were found to dry slowest. [ABSTRACT FROM PUBLISHER]